[Federal Register Volume 81, Number 49 (Monday, March 14, 2016)]
[Proposed Rules]
[Pages 13452-13528]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-05493]
[[Page 13451]]
Vol. 81
Monday,
No. 49
March 14, 2016
Part II
Department of Transportation
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Federal Aviation Administration
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14 CFR Parts 21, 23, 35, et al.
Revision of Airworthiness Standards for Normal, Utility, Acrobatic,
and Commuter Category Airplanes; Proposed Rule
Federal Register / Vol. 81 , No. 49 / Monday, March 14, 2016 /
Proposed Rules
[[Page 13452]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 21, 23, 35, 43, 91, 121, and 135
[Docket No.: FAA-2015-1621; Notice No. 16-01]
RIN 2120-AK65
Revision of Airworthiness Standards for Normal, Utility,
Acrobatic, and Commuter Category Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to amend its airworthiness standards for
normal, utility, acrobatic, and commuter category airplanes by removing
current prescriptive design requirements and replacing them with
performance-based airworthiness standards. The proposed standards would
also replace the current weight and propulsion divisions in small
airplane regulations with performance- and risk-based divisions for
airplanes with a maximum seating capacity of 19 passengers or less and
a maximum takeoff weight of 19,000 pounds or less. The proposed
airworthiness standards are based on, and would maintain, the level of
safety of the current small airplane regulations. Finally, the FAA
proposes to adopt additional airworthiness standards to address
certification for flight in icing conditions, enhanced stall
characteristics, and minimum control speed to prevent departure from
controlled flight for multiengine airplanes. This notice of proposed
rulemaking addresses the Congressional mandate set forth in the Small
Airplane Revitalization Act of 2013.
DATES: Send comments on or before May 13, 2016.
ADDRESSES: Send comments identified by docket number FAA-2015-1621
using any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your
comments electronically.
Mail: Send comments to Docket Operations, M-30; U.S.
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
Hand Delivery or Courier: Take comments to Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200
New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: In accordance with 5 U.S.C. 553(c), DOT solicits comments
from the public to better inform its rulemaking process. DOT posts
these comments, without edit, including any personal information the
commenter provides, to www.regulations.gov, as described in the system
of records notice (DOT/ALL-14 FDMS), which can be reviewed at http://www.dot.gov/privacy.
Docket: Background documents or comments received may be read at
http://www.regulations.gov at any time. Follow the online instructions
for accessing the docket or go to the Docket Operations in Room W12-140
of the West Building Ground Floor at 1200 New Jersey Avenue SE.,
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays.
FOR FURTHER INFORMATION CONTACT: For technical questions concerning
this action, contact Lowell Foster, Regulations and Policy, ACE-111,
Federal Aviation Administration, 901 Locust St., Kansas City, MO 64106;
telephone (816) 329-4125; email lowell.foster@faa.gov.
SUPPLEMENTARY INFORMATION: Later in this preamble, under the Additional
Information section, we discuss how you can comment on this proposal
and how we will handle your comments. This discussion includes related
information about the docket, privacy, and the handling of proprietary
or confidential business information. We also discuss how you can get a
copy of this proposal and related rulemaking documents.
All sections of part 23 would contain proposed revisions, except
the FAA would not make any substantive changes to the following
sections: Sec. Sec. 23.1457, Cockpit Voice Recorders, and 23.1459,
Flight Data Recorders. The only proposed changes to Sec. 23.1459 would
be for the purpose of aligning part 23 references. These sections are
nevertheless included in this proposed revision for context.
Table of Contents
I. Executive Summary
A. Purpose and History of the Proposed Performance-Based
Standards
B. Summary of Major Provisions
1. Performance Standards and Airplane Crashworthiness
2. Loss of Control
3. Icing Certification Standards
C. Cost and Benefits
II. Authority for This Rulemaking
III. Background
A. Part 23 History
B. New Safety Requirements
C. Benefits for the Existing Fleet
D. Conforming Amendments and Other Minor Amendments
E. Public Policy Implementation
1. Regulatory Planning and Review
2. Consensus Standards
3. International Cooperation Efforts for Reorganizing Part 23
F. Means of Compliance
G. FAA Strategic Initiatives
IV. Discussion of Proposal
A. Reorganization of Airworthiness Standards Based on Risk and
Performance
B. Introduction of Simple Airplanes
C. Establishing Performance-Based Standards and the Use of Means
of Compliance
D. Crashworthiness as an Illustration of the Benefits of
Performance-Based Regulations
E. Additional Requirements To Prevent Loss of Control
F. Additional Requirements for Flight in Icing Conditions
G. Production of Replacement and Modification Articles
V. Key Terms and Concepts Used in This Document
VI. Discussion of the Proposed Regulatory Amendments
A. Part 23, Airworthiness Standards
1. Subpart A--General
2. Subpart B--Flight
3. Subpart C--Structures
4. Subpart D--Design and Construction
5. Subpart E--Powerplant
6. Subpart F--Equipment
7. Subpart G--Flightcrew Interface and Other Information
8. Appendices to Part 23
B. Miscellaneous Amendments
1. Production of Replacement and Modification Articles (Sec.
21.9)
2. Designation of Applicable Regulations (Sec. 21.17)
3. Issuance of Type Certificate: Primary Category Aircraft
(Sec. 21.24)
4. Flight Tests (Sec. 21.35)
5. Instructions for Continued Airworthiness and Manufacturer's
Maintenance Manuals Having Airworthiness Limitations Sections (Sec.
21.50)
6. Designation of Applicable Regulations (Sec. 21.101)
7. Applicability (Sec. 35.1)
8. Fatigue Limits and Evaluation (Sec. 35.37)
9. Altimeter System Test and Inspection (Appendix E to Part 43)
10. Powered Civil Aircraft With Standard Category U.S.
Airworthiness Certificates: Instrument and Equipment Requirements
(Sec. 91.205)
11. Restricted Category Civil Aircraft: Operating Limitations
(Sec. 91.313)
12. Increased Maximum Certification Weights for Certain
Airplanes Operated in Alaska (Sec. 91.323)
13. Second In Command Requirements (Sec. 91.531)
14. Additional Emergency Equipment (Sec. 121.310)
15. Additional Airworthiness Requirements (Sec. 135.169)
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VII. Regulatory Notices and Analyses
A. Regulatory Evaluation Summary
B. Initial Regulatory Flexibility Determination
C. International Trade Impact Assessment
D. Unfunded Mandates Assessment
E. Paperwork Reduction Act
F. International Compatibility and Cooperation
G. Environmental Analysis
H. Regulations Affecting Intrastate Aviation in Alaska
VIII. Executive Order Determination
A. Executive Order 13132, Federalism
B. Executive Order 13211, Regulations That Significantly Affect
Energy Supply, Distribution, or Use
IX. Additional Information
A. Comments Invited
B. Availability of Rulemaking Documents
Appendix 1 to the Preamble--Current to Proposed Regulations Cross-
Reference Table
Appendix 2 to the Preamble--Abbreviations and Acronyms Frequently
Used In This Document
I. Executive Summary
A. Purpose and History of the Proposed Performance-Based Standards
Part 23 of Title 14 of the Code of Federal Regulations (14 CFR)
prescribes airworthiness standards for issuance and amendment of type
certificates for airplanes with a passenger-seating configuration of 19
or less and a maximum certificated takeoff weight of 19,000 pounds or
less. Airplanes certificated under part 23 are typically used for
recreation, training, personal travel, and limited commercial
applications.
The current part 23 airworthiness standards are largely
prescriptive, meaning that they describe detailed design requirements,
and are based on airplane designs from the 1950's and 1960's. As a
result of this prescriptive framework, the FAA often requires a design
approval applicant seeking to incorporate new or innovative technology
to provide additional documentation that typically results in the FAA's
issuance of special conditions, exemptions, or equivalent level of
safety (ELOS) findings.\1\ The FAA recognizes that these additional
procedures and requirements are costly to the FAA and industry, act as
barriers to certification, and discourage innovation. Therefore, to
encourage the installation of new safety-enhancing technology and
streamline the certification process, the FAA proposes replacing the
prescriptive requirements found in the current part 23 with
performance-based standards.
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\1\ Special conditions give the manufacturer permission to build
the aircraft, engine or propeller with additional capabilities not
addressed in the regulations. A petition for exemption is a request
to the FAA by an individual or entity asking for relief from the
requirements of a regulation. Equivalent level of safety findings
are made when literal compliance with a certification regulation
cannot be shown and compensating factors exist which can be shown to
provide an equivalent level of safety. 14 CFR parts 11 and 21
provides information on special conditions and exemptions. FAA Order
8110-112A provides standard procedures for issue paper and
equivalent level of safety memoranda.
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The FAA believes this proposed rulemaking would maintain the level
of safety associated with current part 23, while providing greater
flexibility to applicants seeking certification of their airplane
designs. By doing so, this proposed rulemaking would hasten the
adoption of safety enhancing technology in type-certificated products
while reducing regulatory time and cost burdens for the aviation
industry and FAA. This proposed rulemaking would also reflect the FAA's
safety continuum philosophy,\2\ which balances the need for an
acceptable level of safety with the societal burden of achieving that
level safety, across the broad range of airplane types certificated
under part 23.
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\2\ The FAA's safety continuum philosophy is that one level of
safety may not be appropriate for all aviation. The FAA accepts
higher levels of risk, with correspondingly fewer requirements for
the demonstration of compliance, when aircraft are used for personal
transportation.
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This proposed rulemaking is the result of an effort the FAA began
in 2008 to re-evaluate the way it sets standards for different types of
airplanes. Through this effort, a joint FAA and industry team produced
the Part 23 Certification Process Study \3\ (CPS), which reviewed the
life cycle of part 23 airplanes to evaluate certification processes and
develop recommendations. Two key recommendations were to (1) reorganize
part 23 based on airplane performance and complexity rather than the
existing weight and propulsion divisions, and (2) permit the use of
consensus standards as a means to keep pace with rapidly increasing
design complexity in the aviation industry.
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\3\ See www.regulations.gov (Docket # FAA-2015-1621).
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In 2010, with the CPS as a foundation, the FAA conducted a Part 23
Regulatory Review and held meetings with the public and industry to
gain input on revising part 23. These meetings confirmed strong public
and industry support for the CPS recommendations to revise part 23.
In 2011, the FAA formed the Part 23 Reorganization ARC to consider
further the CPS recommendation to reorganize part 23 based on airplane
performance and complexity and to investigate the use of consensus
standards. The ARC recommendations,\4\ published in 2013, echo the CPS
recommendations.
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\4\ See www.regulations.gov (Docket # FAA-2015-1621).
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On January 7, 2013, Congress passed the Federal Aviation
Modernization and Reform Act of 2012 \5\ (Public Law 112-95; 49 U.S.C.
40101 note) (FAMRA), which requires the Administrator, in consultation
with the aviation industry, to assess the aircraft certification and
approval process. Based on the ARC recommendations and in response to
FAMRA, the FAA began work on this proposed rulemaking on September 24,
2013. Subsequently, on November 27, 2013, Congress passed the Small
Airplane Revitalization Act of 2013 (Public Law 113-53, 49 U.S.C. 44704
note) (SARA), which requires the FAA to issue a final rule revising the
certification requirements for small airplanes by--
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\5\ http://www.gpo.gov/fdsys/pkg/CRPT-112hrpt381/pdf/CRPT-112hrpt381.pdf.
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Creating a regulatory regime that will improve safety and
decrease certification costs;
Setting safety objectives that will spur innovation and
technology adoption;
Replacing prescriptive rules with performance-based
regulations; and
Using consensus standards to clarify how safety objectives
may be met by specific designs and technologies.
The FAA believes that the performance-based-standards component of
this proposal complies with the FAMRA and the SARA because it would
improve safety, reduce regulatory compliance costs, and spur innovation
and the adoption of new technology. This proposal would replace the
weight-and propulsion-based prescriptive airworthiness standards in
part 23 with performance- and risk-based airworthiness standards for
airplanes with a maximum seating capacity of 19 passengers or less and
a maximum takeoff weight of 19,000 pounds or less. The proposed
standards would maintain the level of safety associated with the
current part 23, while also facilitating the adoption of new and
innovative technology in general aviation (GA) airplanes.
B. Summary of Major Provisions
This proposal to revise part 23 has two principal components:
Establishing a performance-based regulatory regime and adding new
certification standards for loss of control (LOC) and icing. Where the
FAA proposes to establish new certification requirements, these
requirements would be adopted within the same performance-based
framework proposed for part 23 as a whole.
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1. Performance Standards and Airplane Crashworthiness
Airplane crashworthiness and occupant safety is an example of how
moving towards performance-based standards and providing greater
flexibility to industry would increase aviation safety. Although the
FAA has over the years incrementally amended part 23 to enhance
occupant safety, these amendments have focused on individual system
components, rather than the safety of the system as a whole. By
building greater flexibility into FAA regulations governing crash
testing, this proposal would allow the aviation industry to develop and
implement novel solutions.
2. Loss of Control
One proposed revision to part 23 would improve general aviation
safety by creating additional certification standards to reduce LOC
accidents. Inadvertent stalls resulting in airplane LOC are the most
common cause of small airplane fatal accidents. These LOC accidents
frequently occur in the traffic pattern or at low altitudes, where the
airplane is too low for a pilot to recover control before impacting the
ground. The proposed revisions would require applicants to use new
design approaches and technologies to improve airplane stall
characteristics and pilot situational awareness to prevent such
accidents.
3. Icing Certification Standards
Another proposed revision to part 23 would improve GA safety by
addressing severe icing conditions. In the 1990s, the FAA became aware
of the need to expand the icing conditions considered during the
certification of airplanes and turbine aircraft engines. In particular,
the FAA determined that revised icing certification standards should
include Supercooled Large Drops (SLD),\6\ mixed phase, and ice
crystals.
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\6\ SLD conditions include freezing drizzle and freezing rain,
which contain drops larger than those specified in appendix C to
part 25, and can accrete aft of wing leading edge ice protection
systems.
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This proposed rule would require manufacturers that choose to
certify an airplane for flight in SLD to demonstrate safe operations in
SLD conditions. For those manufacturers who choose instead to certify
an airplane with a prohibition against flight in SLD conditions, this
proposed rule would require a means for detecting SLD conditions and
showing the airplane can safely exit such conditions. Industry has
indicated that these requirements would not impose significant
additional cost burden on industry because many manufacturers already
have equipped recent airplanes with technology to meet the standards
for detecting and exiting SLD conditions in accordance with current FAA
guidance.
C. Cost and Benefits
The goal of this proposal is to create a cost-effective approach to
certification that facilitates the adoption of new safety enhancing
technologies and allows for alternative means of compliance. The FAA
has analyzed the benefits and costs associated with this NPRM. If the
proposed rule saves only one human life, for example, by improving
stall characteristics and stall warnings, that alone would result in
benefits outweighing the costs. The following table shows these
results.
Estimated Benefits and Costs From 2017 to 2036
[2014 $ millions]
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Costs Safety benefits + cost savings = total benefits
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Total.......................................... $3.9 $19.6 + $12.6 = $32.2.
Present value.................................. 3.9 $6.2 + $5.8 = $12.0.
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Accordingly, the FAA has determined that the proposed rule would be
cost beneficial.
II. Authority for This Rulemaking
The FAA's authority to issue rules on aviation safety is found in
Title 49 of the United States Code. Subtitle I, Section 106 describes
the authority of the FAA Administrator. Subtitle VII, Aviation
Programs, describes in more detail the scope of the agency's authority.
This rulemaking is promulgated under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701. Under that section,
the FAA is charged with promoting safe flight of civil airplanes in air
commerce by prescribing minimum standards required in the interest of
safety for the design and performance of airplanes. This regulation is
within the scope of that authority because it prescribes new
performance-based safety standards for the design of normal, utility,
acrobatic, and commuter category airplanes.
Additionally, this rulemaking addresses the Congressional mandate
set forth in the Small Airplane Revitalization Act of 2013 (Public Law
113-53; 49 U.S.C. 44704 note) (SARA). Section 3 of SARA requires the
Administrator to issue a final rule to advance the safety and continued
development of small airplanes by reorganizing the certification
requirements for such airplanes under part 23 to streamline the
approval of safety advancements. SARA directs that the rule address
specific recommendations of the 2013 Part 23 Reorganization Aviation
Rulemaking Committee (ARC).
III. Background
The range of airplanes certificated under part 23 is diverse in
terms of performance capability, number of passengers, design
complexity, technology, and intended use. Currently, each part 23
airplane's certification requirements are determined by reference to a
combination of factors, including weight, number of passengers, and
propulsion type. The resulting divisions (i.e., normal, utility,
acrobatic, and commuter categories) historically were appropriate
because there was a clear relationship between the propulsion and
weight of the airplane and its associated performance and complexity.
Technological developments have altered the dynamics of that
relationship. For example, high-performance and complex airplanes now
exist within the weight range that historically was occupied by only
light and simple airplanes. The introduction of high-performance,
lightweight airplanes required subsequent amendments of part 23 to
include more stringent and demanding standards--often based on the part
25 requirements for larger transport category airplanes--to ensure an
adequate level of safety for airplanes under part 23. The unintended
result is that some of the more stringent and demanding standards for
high-performance airplanes now apply to the
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certification of simple and low-performance airplanes.
A. Part 23 History
Part 23 originated from performance-based requirements developed by
the Bureau of Air Commerce and the Civil Aeronautics Administration in
the 1930s. These regulations were contained in specific Civil Air
Regulations (CAR) for the certification of aircraft (i.e., CAR 3, 4,
and 4a). These requirements, along with various bulletins and related
documents, were subsequently revised and first published as 14 CFR part
23 in 1964 (29 FR 17955, December 18, 1964). Over the past five decades
and after numerous amendments, part 23 has evolved into a body of
highly complex and prescriptive requirements attempting to codify
specific design requirements, address specific problems encountered
during prior certification projects, and respond to specific
recommendations from the National Transportation Safety Board (NTSB).
Although the intent of the prescriptive language contained in
current part 23 was to increase the level of safety, prevent confusion,
and clarify ambiguities, the current regulations have also restrained
manufacturers' ability to employ new designs and testing methodologies.
The FAA believes moving towards performance-based standards should
significantly reduce or eliminate barriers to innovation and facilitate
the introduction of new safety-enhancing technologies.
In 2008, the FAA conducted a review of part 23 by initiating the
Part 23 CPS. Collaborating with industry, the team's challenge was to
determine the future of part 23, given today's current products and
anticipated future products. The team identified opportunities for
improvements by examining the entire life cycle of a part 23 airplane.
The CPS recommended reorganizing part 23 using criteria focused on
performance and design complexity. The CPS also recommended that the
FAA implement general airworthiness requirements, with the means of
compliance defined in industry consensus standards standards. In 2010,
following the publication of the Part 23 CPS, the FAA held a series of
public meetings to seek feedback concerning the findings and
recommendations. Overall, the feedback was supportive of and in some
cases augmented the CPS recommendations.
One notable difference between the CPS findings and the public
feedback was the public's request that the FAA revise part 23
certification requirements for simple, entry-level airplanes. Over the
past two decades, part 23 standards have become more complex as
industry has generally shifted towards correspondingly complex, high-
performance airplanes. This transition has placed an increased burden
on applicants seeking to certificate smaller, simpler airplanes. Public
comments requested that the FAA focus on reducing the costs and time
burden associated with certificating small airplanes by restructuring
the requirements based on perceived risk. The safety risk for most
simple airplane designs is typically low.
On August 15, 2011, the Administrator chartered the Part 23
Reorganization ARC to consider the following CPS recommendations--
Recommendation 1.1.1--Reorganize part 23 based on airplane
performance and complexity, rather than the existing weight and
propulsion divisions; and
Recommendation 1.1.2--Certification requirements for part
23 airplanes should be written on a broad, general, and progressive
level, segmented into tiers based on complexity and performance.
The ARC's recommendations took into account the FAMRA, which
requires the Administrator, in consultation with the aviation industry,
to assess the aircraft certification and approval process. The purpose
of the ARC's assessment was to develop recommendations for streamlining
and reengineering the certification process to improve efficiency,
reduce costs, and ensure that the Administrator can conduct
certifications and approvals in a manner that supports and enables the
development of new products and technologies and the global
competitiveness of the United States aviation industry.\7\ FAMRA also
directs the Administrator to consider the recommendations from the Part
23 Certification Process Study.\8\
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\7\ Section 312(c)
\8\ Section 312 (b)(6)
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ARC membership represented a broad range of of stakeholder
perspectives, including U.S. and international manufacturers, trade
associations, and foreign civil aviation authorities. The ARC was
supported by FAA subject matter experts from all affected lines of
business, from design and production certification to continued
airworthiness and alterations. The following table identifies ARC
participants:
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U.S. Manufacturers
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Avidyne..................... Bendix-King......... Cessna.
Cirrus...................... Continental Motors.. Cub Crafters.
GAMI........................ Garmin.............. Hawker Beechcraft.
Honda....................... Honeywell........... Kestrel.
Lockheed Martin............. Rockwell-Collins.... Quest.
Sensenich Propellers........ Tamarack Aero....... TruTrak.
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U.S. Organizations
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Aircraft Electronics Aircraft Owners and ASTM.
Association (AEA). Pilots Association
(AOPA).
Experimental Aircraft General Aviation National Air Traffic
Association (EAA). Manufacturers Controllers
Association (GAMA). Association
(NATCA).
RTCA........................ SAE.................
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International Manufacturers
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Dassault Falcon............. Diamond............. Flight Design.
Rotax....................... Socata..............
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[[Page 13456]]
International Civil Aviation Authorities
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European Aviation Safety Transport Canada National Civil
Agency (EASA). Civil Aviation Aviation Agency of
(TCCA). Brazil (ANAC).
Civil Aviation Civil Aviation
Administration of China Authority of New
(CAAC). Zealand.
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Each member or participant on the committee represented an
identified segment of the aviation community, with the authority to
speak for that segment. The ARC also invited subject matter experts to
support specialized working groups and subgroups, as necessary. These
working groups developed recommendations and briefed the ARC as a
whole. The ARC then collectively discussed and voted to accept or
reject the recommendations. All of the recommendations included in the
ARC's report had overwhelming majority agreement.
The ARC noted the prevailing view within industry was that the only
way to reduce the program risk, or business risk, associated with the
certification of new airplane designs was to avoid novel design
approaches and testing methodologies. The certification of new and
innovative products today frequently requires the FAA's use of ELOS
findings, special conditions, and exemptions. These take time,
resulting in uncertainty and high project costs. The ARC emphasized
that although industry needs from the outset to develop new airplanes
designed to use new technology, current certification costs inhibit the
introduction of new technology. The ARC identified prescriptive
certification requirements as a major barrier to installing
safety[hyphen]enhancing modifications in the existing fleet and to
producing newer, safer airplanes.
The ARC also examined the harmonization of certification
requirements among the FAA and foreign civil aviation authorities
(CAAs), and the potential for such harmonization to improve safety
while reducing costs. Adopting performance-based safety regulations
that facilitate international harmonization, coupled with
internationally accepted means of compliance, could result in both
significant cost savings and the enabling of safety-enhancing equipment
installations. The ARC recommended that internationally accepted means
of compliance should be reviewed and voluntarily accepted by the
appropriate aviation authorities, in accordance with a process
established by those authorities. Although each CAA would be capable of
rejecting all or part of any particular means of compliance, the intent
would be to have full civil authority participation in the creation of
the means of compliance to ease acceptance of the means of compliance.
B. New Safety Requirements
The performance-based standards proposed in this NPRM are designed
to maintain the level of safety provided by current part 23
requirements. The current part 23 weight and propulsion divisions were
based on assumptions that do not reflect the diversity of performance
capabilities, design complexity, technology, intended use, and seating
capacity of today's new airplane designs, or the future airplane
designs that will become possible as technology continues to evolve.
The FAA would therefore replace the current divisions with
certification levels 1 thru 4, low performance, high performance, and
simple. Furthermore, this would replace the current divisions within
the individual sections with technical and operational capabilities
focused on the technical drivers (e.g., stall speed, Visual Flight
Rules (VFR) and Instrument Flight Rules (IFR) operations,
pressurization). These types of technical and operational criteria
would apply a more appropriate set of standards to each airplane, and
continue to accommodate the wide range of airplane designs within part
23.
To begin, the FAA proposes to eliminate commuter, utility, and
acrobatic airplane categories from part 23, retaining only a normal
category for all new part 23 type certificated airplane design
approvals. The differences between normal, utility, and acrobatic
categories are currently very limited and primarily affect airframe
structure requirements. Proposed part 23 would continue to allow a
normal category airplane to be approved for aerobatics, provided the
airplane is certificated for the safety factors and defined limits of
aerobatic operations.
In addition, the FAA proposes that airplanes approved for spins be
certificated to aerobatic standards. Under the current Sec. 23.3(b),
the utility category provides airplanes additional margin for the more
stringent inertial structural loads resulting from intended spins and
other maneuvers. An airplane designed with traditional handling
qualities and designed to allow spin training is more susceptible to
inadvertent departure from controlled flight. The FAA therefore
believes that maintaining the current utility category for spin and
limited aerobatic maneuver capable airplanes would negate the largest,
single safety gain expected from this rulemaking action--the
significant reduction in inadvertent stall-related departures from
controlled flight.
Under this proposal, airplanes already certificated in the
commuter, utility, and acrobatic categories would continue to fall
within those categories. Each new airplane design, however, would be
subject to varying levels of analysis, based on the potential risk and
performance of the airplane's design. A more rigorous standard, such as
currently applied to commuter category airplanes, would apply to higher
risk and higher performance airplanes.
The proposed requirements would also include new enhanced standards
for resistance to departure from controlled flight. Recognizing that
the largest number of fatal accidents for part 23 airplanes results
from LOC in flight, the FAA proposes to update certification standards
to address these risks. LOC happens when an airplane enters a flight
regime outside its normal flight envelope or performance capabilities
and develops into a stall or spin, an event that can surprise the
pilot. A pilot's lack of awareness of the state of the airplane in
flight and the airplane's low-speed handling characteristics are the
main causal factors of LOC accidents. Furthermore, stall and departure
accidents are generally fatal because an airplane is often too low to
the ground for the pilot to recover. Improving safety that reduces
stall and LOC accidents would save lives. The FAA is therefore
proposing new rules for stall characteristics and stall warnings that
would result in airplane designs more resistant to inadvertently
departing controlled flight.
Another type of low-speed LOC accident that occurs in significant
numbers involves minimum control speed (VMC) in light twin-
engine airplanes. Virtually all twin-engine airplanes have a
VMC that allows directional control to be maintained after
one engine fails. This speed is usually above the stall speed of the
airplane. However, light twin-engine airplanes typically have limited
climb capability on one engine. In the accidents reviewed by the ARC
and FAA, often in these situations, pilots attempted to maintain a
climb or
[[Page 13457]]
maintain altitude, which slowed the airplane down, rather than looking
for the best landing site immediately, maintaining control the whole
way. If the airplane's speed drops below VMC, the pilot can
lose control. In tying the minimum control speed to the stall speed of
the airplane, pilots, rather than attempting to maintain climb and lose
directional control, would instead react appropriately with stall
training techniques, resulting in a controlled descent rather than a
loss of directional control. This requirement will be on new airplanes
and should add little or no cost because it can be designed in from the
start.
The FAA also has identified a need for improved certification
standards related to operations in severe icing conditions. More
specifically, in the 1990's, the FAA became aware of the need to expand
the icing conditions considered during the certification of airplanes
and turbine aircraft engines, to increase flight safety during some
severe icing conditions. The 1994 accident in Roselawn, Indiana,
involving an Avions de Transport Regional ATR 72 series airplane in SLD
conditions, brought to public and governmental attention safety
concerns about the adequacy of the existing icing certification
standards.
As a result of the 1994 accident, and consistent with related NTSB
recommendations, in 1997 the Administrator tasked the Aviation
Rulemaking Advisory Committee (ARAC) (62 FR 64621, December 8, 1997)
with defining SLD, mixed phase, and ice crystal icing environments, and
designing corresponding safety requirements for those conditions. In
June 2000, the ARAC's task was revised to address only transport
category airplanes. More recent events, such as an Air France Airbus
model A330-203 AF447 \9\ accident, in 2009, highlighted the negative
effects of ice crystals on airspeed indication systems and turbojet
engines.
---------------------------------------------------------------------------
\9\ See www.regulations.gov (Docket #FAA-2015-1621), Air France
A330-203, Flight AF 447 Final Accident Report
---------------------------------------------------------------------------
The FAA ultimately published amendments 25-140 (79 FR 65507,
November 4, 2014) and 33-34 (79 FR 65507, November 4, 2014), Airplane
and Engine Certification Requirements in Supercooled Large Drop, Mixed
Phase, and Ice Crystal Icing Conditions that expanded parts 25 and 33
icing requirements, but did not amend part 23 requirements. On February
19, 2010, the Administrator chartered a Part 23 Icing ARC to review and
recommend SLD, mixed phase, and ice crystal icing conditions
regulations and guidance for part 23. In February 2012, the Part 23
Icing ARC formally identified a need to improve the part 23 regulations
to ensure safe operation of airplanes and engines in SLD and ice
crystal conditions.\10\ In particular, the Part 23 Icing ARC
recommended adopting most of the part 25 icing rules, including the
requirement to show either that an airplane can safely fly in SLD
conditions, or that it can detect and safely exit SLD. The proposals in
this NPRM incorporate the recommendations of the Part 23 Icing ARC.
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\10\ See www.regulations.gov (Docket #FAA-2015-1621)
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C. Benefits for the Existing Fleet
The proposed revisions would benefit owners and modifiers of
existing part 23 airplanes, as well as airplane designers and
manufacturers. Both currently and under this proposal, airplanes may be
modified by: (1) An alteration to an individual airplane; (2) a
supplemental type certificate (STC) for multiple airplanes, or (3) an
amendment to an original type design via an amended type certificate
(TC). This proposal would streamline each of these methods for
modifying airplanes.
The proposed change to Sec. 21.9 would facilitate FAA approval of
low-risk equipment produced for installation in type-certificated
airplanes, thereby streamlining the process for owners to upgrade
equipment on their individual airplanes. An example of how this change
would facilitate safety improvements is the installation of inexpensive
weather display systems in the cockpits of small airplanes. These
systems allow a pilot to view current weather conditions along the
planned flight route and at the destination airport, avoiding
unexpected or deteriorating weather conditions. Since these systems are
not required and because they represent low safety risk from failure,
the FAA believes streamlining its approval process to produce them for
use in existing airplanes could lower costs and increase availability
of these systems.
The proposed changes in the rules would also streamline the process
for design approval holders applying for a type design change, or for a
third party modifier applying for an STC, to incorporate new and
improved equipment in a model or several models of airplanes. Since the
revised part 23 standards would be much less prescriptive, the
certification process for modifications would be simplified.
Certification of an amended TC or STC under the proposed part 23
standards would require fewer special conditions or exemptions,
lowering costs and causing fewer project delays.
D. Conforming Amendments and Other Minor Amendments
References to part 23 appear throughout the FAA's current
regulations. Accordingly, the FAA proposes to amend the following parts
for consistency with the proposed revisions to part 23: Part 21, part
35, part 43, part 91, part 121, and part 135.
The FAA also proposes to revise part 21 to simplify the approval
process for low-risk articles. Specifically, the FAA proposes amending
Sec. 21.9 to allow FAA-approved production of replacement and
modification articles using methods not listed in Sec. 21.9(a). This
proposed change is intended to reduce constraints on the use of non-
required, low risk articles, such as carbon monoxide detectors and
weather display systems.
E. Public Policy Implementation
The intent of this NPRM is to reduce regulatory barriers by
establishing a system based on safety-focused performance requirements
and FAA acceptance--as a means of compliance--of consensus standards.
FAA-accepted consensus standards would add clarity to the certification
process and streamline FAA involvement in the development of means of
compliance. Additionally, adopting performance standards would
significantly reduce the complexity of part 23. Furthermore, the
introduction of airplane certification levels based on risk (i.e.,
number of passengers) and performance (i.e., speed) would advance the
FAA's effort to introduce risk-based decision-making and better align
with the FAA's safety continuum philosophy. Together, the FAA believes
these changes would allow the FAA to provide appropriate oversight
based on the safety continuum and would restore a simple and cost
effective certification process based on proven engineering practices.
1. Regulatory Planning and Review
In accordance with applicable executive orders, the FAA has
determined that the proposed revisions to part 23 are the most cost-
beneficial way of achieving the agency's regulatory objectives. This is
because the proposal would relieve industry of a significant regulatory
burden while maintaining or improving the level of safety under the
regulations. In particular, Executive Order 12866, Regulatory Planning
and Review (58 FR 51735, October 4, 1993), and Executive Order 13563,
Improving
[[Page 13458]]
Regulation and Regulatory Review (76 FR 3821, January 21, 2011), direct
each Federal agency to propose or adopt a regulation only upon a
reasoned determination that the benefits of the intended regulation
justify its costs. This proposal is not an economically ``significant
regulatory action'' as defined in section 3(f) of Executive Order 12866
\11\ and it satisfies Executive Order 13563 by protecting public
health, welfare, safety, while promoting economic growth, innovation,
competitiveness, and job creation.
Under the above-referenced executive orders, when an agency
determines that a regulation is the best available method of achieving
its regulatory objective, the agency must design the regulation or
regulations in the most cost-effective manner. In doing so, each agency
must consider incentives for innovation, consistency, predictability,
enforcement and compliance costs (to the government, regulated
entities, and the public), flexibility, distributive impacts, and
equity. Each agency must identify and assess alternative forms of
regulation and shall specify, to the extent feasible, performance
objectives, rather than specifying the behavior or manner of compliance
that regulated entities must adopt. This proposal meets these
requirements because it would implement performance objectives rather
than a prescriptive methodology, thereby reducing time and cost burdens
on industry and increasing opportunities for innovation.
Executive Order 13610, Identifying and Reducing Regulatory Burdens
(77 FR 28469, May 10, 2012) reiterates the direction from Executive
Order 13563 in stating that our regulatory system must measure, and
seek to improve, the actual results of regulatory requirements. To
promote this goal, agencies are to engage in periodic review of
existing regulations, and are required to develop retrospective review
plans to examine existing regulations in order to determine whether any
such regulations should be modified, streamlined, expanded, or
repealed. The purpose of this requirement is to make the agency's
regulatory program more effective or less burdensome in achieving the
regulatory objectives. In response to Executive Orders13563 and 13610,
agencies have developed and made available for public comment
retrospective review plans. Both the Part 23 Reorganization ARC and
this Part 23 Rulemaking Project are on the Department of
Transportation's retrospective review plans.
2. Consensus Standards
Section 3(c) of SARA requires the Administrator, when developing
regulations, to comply with the requirements of the National Technology
Transfer and Advancement Act of 1995 \12\ (Pub. L. 104-113; 15 U.S.C.
272 note) (NTTAA) and to use consensus standards to the extent
practicable while maintaining traditional methods for meeting part 23.
Section 12(d) of the NTTAA directs Federal agencies to use, either by
reference or by inclusion, voluntary consensus standards in lieu of
government-mandated standards, except where inconsistent with law or
otherwise impractical. The Office of Management and Budget (OMB)
Circular A-119,\13\ Federal Participation in the Development and Use of
Voluntary Consensus Standards and Conformity Assessment Activities,
provides guidance to Executive agencies in implementing the
requirements of the NTTAA.
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\12\ http://www.gpo.gov/fdsys/pkg/PLAW-104publ113/pdf/PLAW-104publ113.pdf.
\13\ https://www.whitehouse.gov/omb/circulars_a119/.
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Accordingly, the FAA proposes to accept consensus standards as a
means of compliance with the proposed part 23 performance-based
regulations. The use of consensus standards would be one means of
compliance with the performance-based standards of the proposed part
23. Compliance with the current prescriptive provisions within current
part 23 would be yet another means of compliance available under this
proposal. Applicants would still have the option to propose their own
means of compliance as they do today. The process for reviewing new
means of compliance would not change substantially from the process in
place today.
Although a consensus standard works in some cases, the Part 23
Reorganization ARC expressed concerns that a consensus standard could
be biased in favor of a few large manufacturers and thereby create an
unfair competitive advantage. OMB Circular A-119 also cautions
regulators to avoid such potential biases. The FAA notes that industry
groups associated with the Part 23 Reorganization ARC identified ASTM
International (ASTM) as the appropriate organization to initiate the
development of consensus standards, and that ASTM permits any
interested party to participate in the committees developing consensus
standards. The FAA expects other consensus standards bodies to allow
similar opportunities for interested parties to participate in their
standards-development work. In addition to consensus standards and the
current prescriptive design standards in part 23, any individual or
organization may develop its own proposed means of compliance that may
be submitted to the FAA for acceptance.
3. International Cooperation Efforts for Reorganizing Part 23
Executive Order 13609, Promoting International Regulatory
Cooperation (77 FR 26413, May 4, 2012), promotes international
regulatory cooperation to meet shared challenges and reduce, eliminate,
or prevent unnecessary differences in regulatory requirements.
Consistent with this Order, the FAA's proposal would address
unnecessary differences in regulatory requirements between the United
States and its major trading partners. The U.S. GA industry has
repeatedly informed the FAA of the high costs to address differences
between the airworthiness requirements of the FAA and foreign CAAs. The
FAA believes this proposal has the potential to achieve long-term
harmonization at an unprecedented level, and should result in a
significant savings for both U.S. manufacturers exporting products
abroad and foreign manufacturers exporting products to the U.S. The FAA
requests comments regarding the potential cost savings.
The work of the Part 23 Reorganization ARC forms the foundation of
the proposed changes to part 23. From the onset, the ARC was a
cooperative, international effort. Representatives from several foreign
CAAs \14\ and international members from almost every GA manufacturer
of airplanes and avionics participated in the Part 23 Reorganization
ARC. Several international light-sport aircraft manufacturers, who were
interested in certificating their products using part 23 airworthiness
standards, also participated. In addition to recommending changes to
part 23, the ARC developed proposals to help reduce certification costs
through more international standardization of certification processes
and reducing or eliminating redundant certification activities
associated with foreign certification.
---------------------------------------------------------------------------
\14\ CAAs included participants from Brazil, Canada, China,
Europe, and New Zealand.
---------------------------------------------------------------------------
After the ARC issued its report, the FAA, foreign CAAs, and
industry continued to work together to refine the ARC rule language
until the FAA began drafting the NPRM in December 2014. This included
formal meetings in July and November of 2014. EASA,
[[Page 13459]]
Transport Canada, other foreign authorities, and industry offered
significant contributions to these efforts.
In addition, the CAAs from Europe, Canada, Brazil, China, and New
Zealand are working to produce rules similar to those contained in this
proposal. EASA, for example, published an Advance Notice of Proposed
Amendment (A-NPA) 2015-06 on March 27, 2015, which sets forth EASA's
concept for its proposed reorganization of CS-23, and on which the FAA
provided comments. Like the FAA's current proposal, EASA's A-NPA was
also based on the proposed ARC language with the goal of harmonization.
Both proposals would adopt performance-based standards that facilitate
the use of consensus standards as a means of compliance.
F. Means of Compliance
This proposal would allow type certificate applicants to use FAA-
accepted means of compliance to streamline the certification process.
This proposal, however, is shaped by two concerns raised in the Part 23
Reorganization ARC. First, the rule needs to clearly state that any
applicant must use a means of compliance accepted by the Administrator
when showing compliance with part 23. The FAA emphasizes that any means
of compliance would require FAA review and acceptance by the
Administrator. Second, although a means of compliance developed by a
consensus standards body (i.e., ASTM, SAE, RTCA, etc.) may be
available, any individual or organization would also be able to submit
its own means of compliance documentation to the Administrator for
consideration and potential acceptance.
The FAA anticipates that both individuals and organizations would
develop acceptable means of complying with the proposed performance
standards. The industry groups associated with the ARC discussed the
development of consensus-based standards and selected ASTM as the
appropriate organization to initiate the effort. A standards
organization such as ASTM could, for example, generate a series of
consensus-based standards for review, acceptance, and public notice of
acceptance by the FAA. The ASTM standards would be one way, but not the
only way, to demonstrate compliance with part 23.
Using means of compliance documents to satisfy compliance with the
proposed performance-based rules would diminish the need for special
conditions, ELOS findings, and exemptions to address new technology
advancements. Once the Administrator accepted a means of compliance, it
could be used in future certification applications unless formally
rescinded. Incorporating the use of consensus standards as a means of
compliance with performance-based regulations would provide the FAA
with the agility to more rapidly accept new technology as it develops,
leverage industry experience and expectations to develop of new means
of compliance documents, and encourage the use of harmonized means of
compliance among the FAA, industry, and foreign CAAs. Although an
applicant would not be required to use previously accepted means of
compliance documents, doing so would streamline the certification
process by eliminating the need for the FAA to develop an issue paper
to address the certification of new technology. Proposed Advisory
Circular 23.10, Accepted Means of Compliance, would describe a process
for applicants to submit proposed means of compliance to the FAA for
acceptance by the Administrator.
The Part 23 Reorganization ARC was also concerned that specialists
in the industry could argue for complex means of compliance when the
FAA would accept a simpler or more cost effective approach. To address
these concerns, the FAA would continue to allow applicants to propose
their own means of compliance when the larger industry standard may be
the appropriate level of safety for one but not all certification
levels, consistent with the guidance in OMB Circular A-119, which
reminds the regulator that the government is responsible to the public
for setting the appropriate level of safety and avoiding any unfair
competitive advantage. Additionally, the FAA proposes to continue to
allow the use of the prescriptive means of compliance currently
codified in part 23 as yet another alternative means of compliance with
proposed part 23. This would not apply, however, to the proposed new
requirements, such as Sec. Sec. 23.200, 23.215, and 23.230.
G. FAA Strategic Initiatives
The FAA's Strategic Initiatives 2014-2018 communicates FAA goals
for addressing the challenges presented by the changing aviation
industry and how the FAA intends to make the U.S. aviation system safer
and smarter, and raise the bar on safety. Specifically, one strategic
initiative is for the FAA to embrace and implement risk-based decision
making approaches, which build on safety management principles to
address emerging safety risks using consistent, data-informed
approaches to make smarter, quicker system-level decisions. By
establishing performance-based regulations, coupled with industry
standards, this proposed rulemaking would provide a calibrated and
globally competitive regulatory structure. This new approach would
increase safety in general aviation by enabling and facilitating
innovation and the implementation of safety enhancing designs in newly
certificated products.
This rulemaking effort also directly supports the FAA's Global
Leadership Initiative, by encouraging global harmonization and the
consistent use of regulations, standards, and practices for general
aviation airplanes.
IV. Discussion of Proposal
A. Reorganization of Airworthiness Standards Based on Risk and
Performance
The FAA proposes replacing the current weight and propulsion-based
airplane certification divisions with airplane certification and
performance levels based on the number of potential passengers and the
performance of the airplane. The FAA believes this proposed regulatory
change would better accommodate the wide range of airplanes
certificated under part 23, thereby reducing certification risk, time,
and costs.
Historically, turbine-powered airplanes were assumed to fly at or
above 18,000 feet (5,486 meters) and at high speeds, whereas piston
engine airplanes were assumed to fly below 18,000 feet (5,486 meters)
and at lower speeds. Today, with advancements in aviation technology,
these general design and performance assumptions may not be valid.
Furthermore, the current regulations do not account for airplanes
equipped with new technologies, such as electric propulsion systems,
which may have features that are entirely different from piston and
turbine engines. For these reasons, the FAA is proposing regulations
based on airplane performance and potential risk rather than on
assumptions about specific technologies. These proposed standards would
be appropriate to each specific airplane design.
Certification of airplanes under part 23 would either be conducted
using airplane certification levels based on maximum passenger seating
configuration and airplane performance levels based on speed, or occur
as so-called ``simple airplanes'' that are low-speed airplanes with a
stalling speed (VSO) <= 45 Knots Calibrated Airspeed (KCAS)
approved only for VFR operations. The FAA proposes the following
airplane certification levels:
[[Page 13460]]
Level 1--for airplanes with a maximum seating
configuration of 0 to 1 passengers, including simple airplanes.
Level 2--for airplanes with a maximum seating
configuration of 2 to 6 passengers.
Level 3--for airplanes with a maximum seating
configuration of 7 to 9 passengers.
Level 4--for airplanes with a maximum seating
configuration of 10 to 19 passengers.
B. Introduction of Simple Airplanes
The regulations contained in part 23 have gradually become more
focused on high-performance, turbine-powered airplanes, and this
emphasis has become a barrier to the efficient certification and
introduction to market of new entry-level, simple airplanes. The Part
23 Reorganization ARC specifically noted that current part 23 does not
have appropriate standards for the certification of entry-level
airplanes.
The FAA proposes to define ``simple airplanes'' in Sec. 23.5 to
recognize the entry-level airplane. Simple airplanes would be limited
to airplane designs that allow transport of no more than one passenger
(in addition to the pilot), are limited to VFR operations, and have
both a low top speed and a low stall speed. These airplanes are similar
to EASA's Certification Specification--Very Light Aeroplanes (CS-VLA),
which are currently imported to the U.S. and certificated as special
class airplanes in accordance with 14 CFR 21.17(b). The proposed change
would allow these airplanes to be certified as normal category
airplanes under part 23.
The FAA believes that permitting certification of simple airplanes
would allow more certified entry-level airplanes to enter the
marketplace. The FAA expects simple airplanes to be a more basic
sublevel within proposed certification level 1, but recognizes that
because of similarities between simple and non-simple airplanes within
certification level 1, creating this category may be unnecessary. For
this reason, the FAA is specifically asking for comments concerning the
utility of creating a separate, simple airplane sublevel.
C. Establishing Performance-Based Standards and the Use of Means of
Compliance
The Part 23 Reorganization ARC was aware the Administrator has
accepted as evidence of compliance various manufacturers' internal
design standards in the past, and the ARC recommended expressly stating
that option in the proposal. Proposed Sec. 23.10, Accepted Means of
Compliance, would allow individual persons or companies to submit their
internal standards as means of compliance for consideration by the
Administrator. Proposed Sec. 23.10 would also require an applicant to
show the FAA how it would demonstrate compliance with this part using a
means of compliance, which may include consensus standards accepted by
the Administrator. It would further require an applicant requesting
acceptance of a means of compliance to provide the means of compliance
to the FAA in a form and manner specified by the Administrator. In
addition, proposed Sec. 23.10 specifically recognizes the use of
consensus standards as a means of compliance that could be acceptable
to the Administrator. If this information is proprietary in nature, it
would be afforded the same protections as are applied today in
certification applications submitted under 14 CFR part 21.
The phrase ``means of compliance'' may have different connotations
depending on its context. Historically, the FAA has treated an
applicant's demonstration of compliance as a means of compliance.
Alternatively, as indicated by sec. 3(b)(4) of the SARA, consensus
standards may constitute a means of compliance that can address new and
novel designs and technologies. In other words, as suggested by the
SARA, an applicant would develop a design to satisfy a performance-
based standard, and the design is the means of complying with the
standard.
Currently, an applicant for a type certificate must show the FAA
how it satisfies the applicable airworthiness standards. The applicant
submits the type design, test reports, and computations necessary to
show compliance. The applicant approaches the FAA and enters into
negotiations regarding what constitutes an adequate demonstration--
testing or analysis. The FAA anticipates that, under the proposed
framework, standards developed by consensus standards bodies would
provide a pre-existing means by which any applicant may demonstrate
compliance with the corresponding performance-based requirements. For
example, the proposed fuel system requirements would be broad enough to
certificate airplanes with electric propulsion systems in which
batteries and fuel cells are used as fuel. Airplanes incorporating
these systems cannot currently be certificated without applying for
special conditions or exemptions.
Elements of this proposal are already in place today. Industry
standards bodies like RTCA, SAE, ASTM, and the European Organization
for Civil Aviation Equipment (EUROCAE) have already developed detailed
means of compliance documents that an applicant for a type certificate
may use to demonstrate compliance with our regulatory requirements in
14 CFR parts 23, 25, 27, and 29. For decades, the FAA has identified
these means of compliance documents as an acceptable means of complying
with our regulatory requirements. This proposal would build on and
expand this aspect of our regulations by also transitioning part 23
towards a regulatory framework based on performance standards.
D. Crashworthiness as an Illustration of the Benefits of Performance-
Based Regulations
One area where the implications of a change from prescriptive to
performance-based requirements are most evident is in the demonstration
of crashworthiness. The current part 23 crashworthiness and occupant
safety requirements are based on seat and restraint technology used in
the 1980's. Currently, an applicant demonstrates crashworthiness by a
sled test. Under the proposed standards, an applicant would not
necessarily have to perform a sled test, but could instead employ a
different method accounting for many other factors, several of which
are described below. The FAA is imposing no new requirements, but
would, under this proposal, provide greater flexibility to adopt new
safety-testing methodologies and, ultimately, more advanced safety
technologies.
The FAA proposes to allow greater flexibility with respect to the
testing and demonstration, similar to advancements made in the
automotive industry over the past 30 years. The proposed regulations
would facilitate evaluation of the entirety of a crashworthiness
system--namely, the interaction of all crashworthiness features--rather
than requiring an evaluation of discrete, individual parameters. A
system's ability to protect occupants can be better understood by
evaluating it as a complete system, and using that greater
understanding to develop and implement new technologies. Such an
evaluation could include analyses of important survivability factors
identified by the NTSB, including occupant restraints, survivable
volume, energy-absorbing seats, and seat retention. These proposed
crashworthiness standards would not necessarily prevent accidents, but
should improve survivability.
The NTSB produced a series of reports in the 1980s that evaluated
over 21,000 GA airplane crashes between 1972 and 1981. The NTSB General
[[Page 13461]]
Aviation Crashworthiness Project \15\ evaluated airplane orientation,
impact magnitudes, and survival rates and factors to provide
information supporting changes in crashworthiness design standards for
GA seating and restraint systems. The NTSB reports also established
conditions approximating survivable accidents and identified factors
that would have the largest impact on safety. Amendment 23-36 (53 FR
30802, August 15, 1988) to part 23 referenced these reports for dynamic
seats but did not adopt a systems-evaluation approach.
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\15\ See www.regulations.gov (Docket # FAA-2015-1621).
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The NTSB reports identified several factors that, working together
as a system, should result in a safer airplane. The assessment also
indicated, however, that shoulder harnesses offer the most immediate
individual improvement for safety. The FAA codified the shoulder
harnesses requirement in amendments 23-19 (42 FR 20601, June 16, 1977)
and 23-32 (50 FR 46872, November 13, 1985) for newly manufactured
airplanes. The FAA also issued policy statement ACE-00-23.561-01,
Methods of Approval of Retrofit Shoulder Harness Installations in Small
Airplanes,\16\ dated September 19, 2000, to streamline the process for
retrofitting older airplanes. Current part 23 requires occupant
restraints to maintain integrity, stay in place on the occupant
throughout an event, properly distribute loads on the occupant, and
restrain the occupant by mitigating interaction with other items in the
cabin. Newer technologies that enhance or supplement the performance of
these restraints, such as airbags, are now being considered for
inclusion in designs. The use of airbags has greatly increased
passenger safety in automobiles, by offering protection in much more
severe impacts and in impacts from multiple directions. The proposed
performance standards would enable the use of these technologies.
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\16\ See www.regulations.gov (Docket # FAA-2015-1621).
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Survivable volume is another critical factor in crashworthiness.
Survivable volume is the ability of the airframe to protect the
occupants from external intrusion, or the airplane cabin crushing
during and after an accident. There were several observed accidents in
the NTSB study where conventional airplane construction simply crushed
an otherwise restrained occupant. Crashworthiness regulations have
never included survivable volume as a factor, except in some instances
in which an airplane turns over. Airplane designs should provide the
space needed for the protection and restraint of the occupants. This is
one of the first steps in the analysis of airplane crashworthiness.
Data from the NTSB General Aviation Crashworthiness Project
suggested that energy-absorbing seats that protect the occupant from
vertical impact loads could enhance occupant survivability and prevent
serious injury, thereby enhancing odds for exiting the airplane and
preventing many debilitating long-term injuries. The FAA established
dynamic seat testing requirements in amendment 23-36 for airplanes
certificated under part 23. Energy absorbing seats have a smaller
impact than some other safety factors because accident impacts with
large vertical components tend to have lower odds of survival.
Nevertheless, energy attenuation from vertical forces, both static and
dynamic, has been important to crashworthiness regulations for the past
25 years. Seats may crush or collapse, but must remain attached to the
body of the airplane. Coupling the seat performance to the rest of the
airframe response is important to the enhancement and understanding of
occupant survivability. The FAA believes allowing designers to consider
airframe deformation would result in more accurate floor impulses,
which relate to simulated crash impact, and may allow for evaluation
for crash impulses in multiple directions.
The NTSB also identified seat retention as another basic building
block for airplane crashworthiness. The NTSB reports show more than a
quarter of otherwise-survivable accidents included instances where the
seats broke free at the attachment to the airplane, resulting in
fatalities or serious injuries. Dynamic seat testing requirements
address the ability of seat assemblies to remain attached to the floor,
even when the floor shifts during impact. Pitching and yawing of the
seat tracks during dynamic seat tests demonstrates the gimbaling and
flexibility of the seat.
The FAA believes that, under this proposal, all of these
crashworthiness factors could be incorporated into future testing
methodologies and thereby increase the survivability of accidents in
part 23 certificated airplanes. This proposed part 23 amendment would
authorize design approval applicants to use these technologies and
testing methodologies to enhance occupant safety.
E. Additional Requirements To Prevent LOC
LOC continues to be the leading cause of fatal GA accidents. The
FAA identified 74 accidents caused by stall or LOC between January 2008
and December 2013. These accidents, which are listed in Appendix IV of
the Part 23 Regulatory Evaluation,\17\ represent the type of accidents
that could be prevented by the proposed new stall and LOC requirements.
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\17\ See www.regulations.gov (Docket # FAA-2015-1621).
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The FAA proposes to add requirements in Sec. Sec. 23.200 and
23.215 to prevent LOC accidents. Inadvertent stalls resulting in
airplane LOC cause a large number of small airplane fatal accidents.
These LOC accidents in the traffic pattern or at low altitudes often
result in fatalities because the airplane is too low to the ground for
the pilot to recover control. The FAA therefore believes it can improve
safety by requiring applicants to use new approaches to improve
airplane stall characteristics to prevent such accidents.
Another type of low-speed LOC accident that occurs in significant
numbers involves VMC in light twin-engine airplanes.
Virtually all twin-engine airplanes have a VMC that allows
directional control to be maintained after one engine fails. This speed
is typically above the stall speed of the airplane. However, light
twin-engine airplanes also typically have limited climb capability on
one engine. Moreover, after the failure of one engine, pilots often
instinctively tend to try to maintain a climb or maintain altitude,
which slows the airplane down. If the speed drops below VMC,
the pilot can lose control of the airplane. Because pilots tend to be
more aware of the airplane's stall speed, the FAA proposes in Sec.
23.200 that certification levels 1 and 2 multiengine airplanes would be
required to have a VMC that does not exceed the stall speed
of the airplane for each configuration. The FAA believes this proposed
requirement would provide a higher level of safety than current Sec.
23.149. The FAA requests comments on this proposal.
The FAA also proposes new requirements in Sec. 23.215 for airplane
stall characteristics and stall warning that would result in airplane
designs more resistant to inadvertently stalling and departing
controlled flight. These proposed requirements would increase the level
of safety over the current requirements. At the same time, the FAA
proposes to eliminate the spin recovery requirement in the current
rules for normal category airplanes. The FAA believes the spin recovery
requirement is unnecessary for normal category airplanes because the
vast
[[Page 13462]]
majority of inadvertent stalls leading to spin entry occur below a safe
altitude for spin recovery. However, airplanes certificated for
aerobatics would still have to meet spin recovery requirements.
The FAA also proposes to address pilot stall awareness by requiring
warnings that are more effective and by allowing new approaches to
improve pilot awareness of stall margins. These warnings could be as
simple as angle of attack or energy awareness presentations, or
sophisticated envelope protection systems that add a forward force to
the pilot's controls as the airplane speed and attitude approach stall.
F. Additional Requirements for Flight in Icing Conditions
The FAA proposes to implement the Part 23 Icing ARC's
recommendations in Sec. Sec. 23.230, 23.940 and 23.1405, to allow an
applicant the option of certifying an airplane to operate in SLD icing
conditions. To do so, an applicant would be required to meet the same
safety standards in SLD icing conditions as currently demonstrated for
part 23 airplanes in the icing conditions defined in appendix C to part
25.
Currently, the FAA does not certify part 23 airplanes to operate in
SLD icing conditions, also known as freezing drizzle and freezing rain.
Instead, current part 23 icing regulations require airplane
performance, flight characteristics, systems, and engine operation to
be demonstrated in the icing conditions defined in appendix C to part
25, which does not contain SLD icing conditions. In 2012, prior to the
Part 23 Reorganization ARC, the Part 23 Icing ARC recommended revising
part 23 to include SLD icing requirements in subparts B, E, and F
(Flight, Powerplant, and Equipment, respectively).
If an applicant chooses not to certify an airplane in SLD icing
conditions, proposed Sec. 23.230 would require the applicant to
demonstrate that SLD icing conditions could be detected and safely
exited. A means of compliance for SLD detection and exit may be found
in FAA Advisory Circular 23.1419-2D, Certification of Part 23 Airplanes
for Flight in Icing Conditions.\18\ The service history of airplanes
certificated under part 23 and certified to the latest icing standards
has shown that AC 23.1419-2D provides an adequate level of safety for
detecting and safely exiting SLD icing conditions. Industry has
indicated that these requirements would not impose an additional burden
because many manufacturers have already equipped recent airplanes to
meet the standards for detecting and exiting SLD in accordance with
current FAA guidance. Proposed Sec. 23.230, along with proposed Sec.
23.940, Powerplant ice protection, and Sec. 23.1405, Flight in icing
conditions, and their respective means of compliance, address NTSB
safety recommendations A-96-54 and A-96-56. The following table
provides a summary of the proposed icing regulations.
---------------------------------------------------------------------------
\18\ See www.regulations.gov (Docket # FAA-2015-1621).
Proposed Icing Regulations
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Airframe and system
protection,
performance and
flight
Part 23 type certificate Engine protection characteristics
limitations (Sec. 23.940) requirements (Sec.
Sec. 23.230,
23.1300, and
23.1405)
------------------------------------------------------------------------
Not certified for flight in Safe in part 25, App None, except pitot
icing conditions. C conditions, heat required if
ground ice fog, and airplane certified
falling/blowing for flight in
snow. instrument
meteorological
conditions (IMC).
Certified for flight in Safe in part 25, App Safe in part 25, App
icing conditions, but C conditions, C conditions. Can
prohibited for flight in ground ice fog, and detect SLD and
SLD. falling/blowing safely exit.
snow.
Certified for flight in Safe in part 25, App Safe in part 25, App
icing conditions and SLD. C conditions, C conditions and
ground ice fog, and SLD.
falling/blowing
snow, and SLD.
------------------------------------------------------------------------
G. Production of Replacement and Modification Articles
The Part 23 Reorganization ARC recommended simplifying
certification requirements for non-required systems and equipment, with
an emphasis on improvement in overall fleet safety from the prevailing
level. In the past, the FAA has not established different production
requirements for required and non-required equipment that may enhance
safety, or for articles whose improper operation or failure would not
cause a hazard. The current requirements for producing articles and
representing those articles as suitable for installation on type-
certificated products are well suited for articles manufactured in
accordance with a product's TC or STC, as well as for TSO and PMA
parts. However, they may unnecessarily constrain the production of non-
required, low risk articles.
Current standards for the production approval of these articles can
create a barrier for their installation in the existing fleet of
aircraft. Examples of such articles include carbon monoxide detectors,
weather display systems, clocks, small hand-held fire extinguishers,
and flashlights. In many cases, these articles are ``off-the-shelf''
products. It is frequently difficult for a person to install these
articles on a type-certificated aircraft because the level of design
and production details necessary for these articles to meet the
provisions of current Sec. 21.9, as expected for more critical
articles, are frequently unavailable.
The FAA is therefore proposing to revise Sec. 21.9, Replacement
and Modification Articles, to provide applicants with an alternative
method to obtain FAA approval to produce replacement and modification
articles. This proposed change would allow a production approval
applicant to submit production information for a specific article,
without requiring the producer of the article to obtain approval of the
article's design or approval of its quality system. The FAA intends to
use the flexibility provided by this proposal to streamline the
approval process for non-required safety enhancing equipment and other
articles that pose little or no risk to aircraft occupants and the
public. The FAA requests comments on this proposal, and particularly is
interested in comments regarding whether the proposed change would
safely facilitate retrofit of low risk articles and whether there are
alternative methods to address the perceived retrofit barrier.
V. Key Terms and Concepts Used in This Document
The proposal includes a number of terms introduced into the
regulations for the first time. These terms may be used
[[Page 13463]]
to replace existing prescriptive requirements or may explain other
terms that have had longstanding use in the aircraft certification
process, but in context of this rulemaking proposal, the FAA wants to
specify its meaning. These terms are intended to set forth and clarify
the safety intent of the proposed rules. Although certain terms may
differ from those currently in use, these differences are not intended
to increase the regulatory burden on an applicant unless specifically
stated. The FAA's intent is that the proposed requirements
incorporating these new terms not change the intent, understanding, or
implementation of the original rule unless that requirement has been
specifically revised in the proposal, such as is the case for
requirements governing stall characteristics. To assist applicants in
understanding the intent of the proposal, these terms are discussed
below:
Airplane Certification Level--A division used for the certification
of airplanes that is associated directly with the number of passengers
on the airplane. Airplane certification levels would be established to
implement the agency's concept of certificating airplanes using a
process that recognizes a safety continuum.
Airplane Performance Level--Maximum airspeed divisions that are
intended, along with airplane certification levels, to replace current
weight and propulsion divisions used for the certification of
airplanes. Current propulsion-based divisions assume that piston engine
airplanes are slower than turbine-powered airplanes. Current weight-
based divisions assume that heavier airplanes are more complex and
would be more likely to be used in commercial passenger carriage than
lighter airplanes. These assumptions are no longer valid. Airplane
certification based on performance levels would apply regulatory
standards appropriate to airplane's performance and complexity.
Departure Resistant--For the purposes of this NPRM, departure
resistant refers to stall characteristics that make it very difficult
for the airplane to depart controlled flight. Most fatal stall or spin
accidents start below 1000 feet above ground level and do not actually
spin, but start a yawing and rolling maneuver to enter the spin called
a post stall gyration. In these low-altitude accidents, the airplane
typically hits the ground before completing one turn. Therefore, the
important safety criterion is preventing the airplane from exhibiting
stall characteristics that could result in a departure from controlled
flight.
Entry-Level Airplane--A two or four-place airplane typically used
for training, rental, and by flying clubs. Historically, most of these
airplanes have four cylinder engines with less than 200 horsepower.
These airplanes typically have fixed-gear and fixed-pitch propellers,
but may also have retractable landing gear and constant speed
propellers. Entry-level airplanes typically cannot be used to train
pilots to meet the requirements to operate a complex aircraft, as that
term is defined for airman certification purposes.
Equivalent Level of Safety (ELOS) Finding--A finding made by the
accountable aircraft certification directorate when literal compliance
with a certification requirement cannot be shown and compensating
factors in the design can be shown to provide a level of safety
equivalent to that established by the applicable airworthiness
standard.
Fuel--Any source used by the powerplant to generate its power.
Hazard--Any existing or potential condition that can lead to
injury, illness or death; damage to or loss of a system, equipment, or
property; or damage to the environment. A hazard is a condition that is
a prerequisite to an accident or an incident. (Cf. Order VS 8000.367,
Appendix A)
Issue Paper--A structured means for describing and tracking the
resolution of significant technical, regulatory, and administrative
issues that occur during a certification project. The issue paper
process constitutes a formal communication vehicle for addressing
significant issues among an applicant, the FAA, and if applicable, the
validating authority (VA) or certificating authority (CA) for type
validation programs. An issue paper may also be used to address novel
or controversial technical issues.
Means of Compliance--A documented procedure used by an applicant to
demonstrate compliance to a performance or outcome-based standard.
Similar to an Advisory Circular (AC), a means of compliance is one
method, but not the only method, to show compliance with a regulatory
requirement. Additionally, if a procedure is used as a means of
compliance, it must be followed completely to maintain the integrity of
the means of compliance.
Performance- or Outcome-Based Standard--A standard that states
requirements in terms of required results, but does not prescribe any
specific method for achieving the required results. A performance-based
standard may define the functional requirements for an item,
operational requirements, or interface and interchangeability
characteristics.
Pilot or Flightcrew--This is used generically throughout the
proposed part 23 because part 23 has airplanes approved for single
pilot operations as well as and two flightcrew members. For most
airplanes certificated under part 23 that are single pilot, applicants
should consider pilot and flightcrew to be interchangeable.
Prescriptive Design Standard--Specifies a particular design
requirement, such as materials to be used, how to perform a test, or
how an item is to be fabricated or constructed. (Cf. OMB Circular A-119
Section 5.f.)
Safety Continuum--The concept that one level of safety is not
appropriate for all aviation activities. Accordingly, higher levels of
risk, with corresponding requirements for less rigorous safety
demonstrations for products, are accepted as aircraft are utilized for
more personal forms of transportation.
Survivable Volume--The airplane cabin's ability to resist external
intrusion or structural collapse during and after impact. The ability
to resist is usually represented as a stiffer design around the cabin
(not unlike a racecar roll cage) that is generally stronger than the
surrounding structure. While the airframe may deform or disintegrate
and attenuate impact energy, the cabin of the airplane will still
maintain its integrity and protect the occupants restrained within.
During otherwise survivable accident scenarios, including rollover,
this structure should maintain its shape under static and dynamic
loading conditions.
VI. Discussion of the Proposed Regulatory Amendments
A. Part 23, Airworthiness Standards
1. Subpart A--General
a. General Discussion
The FAA proposes eliminating the utility, acrobatic, and commuter
categories for future airplanes certificated under part 23. The FAA
also proposes to change from weight and propulsion divisions to
performance and risk divisions. This would address the wide range of
airplanes to be certificated under part 23 and enhance application of
the safety continuum approach. Appendix 1 of this preamble contains a
cross-reference table detailing how the current regulations are
addressed in the proposed part 23 regulations.
[[Page 13464]]
b. Specific Discussion of Changes
i. Proposed Sec. 23.1, Applicability and Definition
Proposed Sec. 23.1 would prescribe airworthiness standards for the
issuance of type certificates, and changes to those certificates, for
airplanes in the normal category. Current Sec. 23.3, Airplane
categories, defines normal category as airplanes that have a seating
configuration, excluding pilot seats, of nine or less, a maximum
certificated takeoff weight of 12,500 pounds or less, and intended for
nonacrobatic operation. Proposed Sec. 23.1 would delete references to
utility, acrobatic, and commuter category airplanes, and paragraph (b)
would not include the current reference to procedural requirements for
showing compliance. The reference to procedural requirements for
showing compliance is redundant with the requirement in Sec. 21.21,
Issue of type certificate: Normal, utility, acrobatic, commuter, and
transport category aircraft; manned free balloons; special classes of
aircraft; aircraft engines; propellers, to show compliance. Proposed
Sec. 23.1 would also add three definitions specific to part 23: (1)
Continued safe flight and landing, (2) designated fire zone, and (3)
empty weight.
ii. Proposed Sec. 23.5, Certification of Normal Category Airplanes
Proposed Sec. 23.5 would apply certification in the normal
category to airplanes with a passenger-seating configuration of 19 or
less and a maximum certificated takeoff weight of 19,000 pounds or
less. Proposed Sec. 23.5 would also establish certification levels
based on the passenger seating configuration and airplane performance
levels based on speed.
The diversity of airplanes certificated under part 23 is large
relative to performance, numbers of passengers, complexity, technology,
and intended use. Airplane certification requirements under part 23 are
currently determined using a combination of weight, numbers of
passengers, and propulsion type. These divisions historically were
appropriate because there was a clear relationship between the
propulsion and weight of the airplane and its associated performance
and complexity. Recent technological developments have altered the
dynamics of this relationship. High-performance and complex airplanes
now exist within the weight range that was typical for light and simple
airplanes. Furthermore, current part 23 has evolved to meet the
additional regulatory requirements resulting from the introduction of
high-performance airplanes. This has resulted in the introduction of
more stringent and demanding requirements in the lower weight airplanes
such as the use of 14 CFR part 25 based requirements for simple,
single-engine turbine airplanes. The result is that some of the current
requirements have become more demanding for simple and low-performance
airplanes.
The FAA proposes replacing the current part 23 weight and
propulsion divisions because they were based on assumptions that do not
always fit the large diversity of airplane performance, complexity,
technology, intended use, and seating capacity encompassed in today's
new airplane designs. Also, the current divisions may not be
appropriate to address unforeseen designs of the future. The commuter
category, originally intended for the certification of airplanes over
12,500 pounds and up to 19 passengers, is currently used for larger
business jets with less than ten passengers. The proposed certification
and performance level approach, while different from the current
divisions, would capture the safety intent of part 23 more
appropriately than the current propulsion and weight divisions.
The FAA proposes replacing the current divisions with specific
technical and operational capabilities by addressing, for example,
stall speed, VFR/IFR operation, pressurization, etc., that represent
the actual technical drivers for current prescriptive requirements.
These types of design specific technical and operational criteria would
be more appropriate for a means of compliance document where a complete
range of airplane designs could be addressed. The FAA proposes that
high-speed, multiengine airplanes and multiengine airplanes over 12,500
pounds should continue meeting the equivalent commuter category
performance-based requirements. The proposed performance requirements
would be based on number of passengers (certification level) and
airplane performance (performance level); not weight or propulsion
type.
The FAA proposes to eliminate commuter, utility, and acrobatic
airplane categories in part 23, retaining only normal category for all
new part 23 type certificated airplane design approvals. The FAA
believes this action would not affect the existing fleet of small
airplanes. For example, the commuter category was originally introduced
into part 23 to apply to a 10 to 19 passenger, multiengine airplane,
operated in scheduled service under 14 CFR parts 121 and 135. However,
new airplanes certified under part 23 can no longer be used in
scheduled service under part 121 because Sec. 121.157, Aircraft
certification and equipment requirements, paragraph (h), requires a
part 25 certification for newly type certificated airplanes. The
majority of airplanes recently certified in the commuter category are
multiengine business jets. Additionally, the certification category of
commuter can be confused with the same term in the operating rules
because the term is defined differently in the certification and
operation rules. The FAA recognizes that moving away from weight and
propulsion divisions would result in changes for the criteria used to
determine when to apply the existing commuter category certification
requirements using the numbers of passenger seats (excluding crewmember
seats), performance, and technical divisions proposed in this NPRM. The
FAA proposes the following airplane certification levels:
Level 1--for airplanes with a maximum seating
configuration of 0 to 1 passengers.
Level 2--for airplanes with a maximum seating
configuration of 2 to 6 passengers.
Level 3--for airplanes with a maximum seating
configuration of 7 to 9 passengers.
Level 4--for airplanes with a maximum seating
configuration of 10 to 19 passengers.
The differences between normal, utility, and acrobatic categories
are currently very limited and primarily affect airframe structure
requirements. Proposed part 23 would still allow a normal category
airplane to be approved for aerobatics provided the airplane was
certified to address the factors affecting safety for the defined
limits for that kind of operation. Currently, the utility category
provides airplanes additional margin for the more stringent inertial
structural loads resulting from intended spins and the additional
maneuvers stated in the requirements of the utility category in Sec.
23.3(b). The FAA proposes that airplanes approved for spins be
certificated to aerobatic standards. An airplane designed with
traditional handling qualities and designed to allow spin training is
more susceptible to inadvertent departure from controlled flight. The
FAA believes that maintaining the current utility category for
airplanes approved for spins and limited aerobatic maneuvers would
negate the single largest safety gain expected from this rulemaking
action--the significant reduction in inadvertent stall-related
departures from controlled flight.
Proposed Sec. 23.5(c) would categorize the performance level of an
airplane as low speed or high speed. The combination of certification
levels and performance levels is intended to
[[Page 13465]]
provide divisions that address the actual safety concern of occupant
numbers and performance, for example, future designs using novel
propulsion methods. The FAA proposes the following airplane performance
levels:
Low speed--for airplanes with a design cruising speed
(VC) or maximum operating limit speed (VMO) <=
250 KCAS (or MMO <= 0.6).
High speed--for airplanes with a VC or
VMO > 250 KCAS (or MMO > 0.6).
Proposed Sec. 23.5(d) would identify a simple airplane as one with
a certification level 1, a VC or VMO <= 250 KCAS
(and MMO <= 0.6), and a VSO <= 45 KCAS, and
approved only for VFR operations. The FAA proposes a simple airplane as
equivalent to airplanes certificated under EASA's current CS-VLA. In
most cases, EASA's CS-VLA requirements are identical to the proposed
corresponding part 23 requirements and have been proposed in the
requirements for certification level 1 airplanes. The FAA considered
using the CS-VLA standards in combination with the proposed part 23
certification standards for all certification level 1, low-speed
airplanes. However, the FAA believes that there are several
requirements in CS-VLA that are not appropriate for all certification
level 1, low-speed airplanes, such as no requirement for a type
certified engine in CS-VLA. Therefore, the FAA proposes creating a
limited certification and performance level for simple airplanes.
Simple airplanes would be a subset of certification level 1, low-speed
airplanes and would have a VSO <= 45 KCAS and would only be
approved for VFR operations.
In accordance with the FAA's objective to remove weight and
propulsion divisions from the rules and use performance and
certification divisions, the proposed requirements applicable to the
certification of simple airplanes would not completely conform to the
criteria EASA uses to certificate very light airplanes. The FAA
proposes that simple airplanes would constitute a subset of
certification level 1, low-speed airplanes that would be required to
have a low stall speed limit and a VFR limitation in order to maintain
a level of safety appropriate for these airplanes. The FAA believes
that creating the simple certification level would encourage
manufacturers of light-sport and experimental aircraft kits to pursue
type certificates for their airplane designs without encountering the
administrative, procedural or regulatory barriers existing in current
part 23, while allowing innovative technology in those designs.
The FAA considered allowing airplanes that meet the consensus
standards applicable to the certification of special light-sport
aircraft to be included in proposed part 23. However, the FAA decided
that this would not be in the best interest of the GA community because
it could result in the elimination of the special light-sport aircraft
category. There are advantages in the certification of special light-
sport aircraft, such as self-certification, that would not be available
if the aircraft were type certificated under part 23. This proposal
would instead enable a simpler path to part 23 certification for
airplanes that meet the definition of a light-sport aircraft and wish
to pursue a type of certificate for business reasons.
The FAA expects simple airplanes to be more basic than the proposed
certification level 1, low-speed airplanes. A simple airplane is a
certification level 1, low-speed airplane with a stall speed limit of
45 KCAS that would be limited to VFR operations. The FAA recognizes
that a simple airplane level would have characteristics very similar to
certification level 1, low-speed airplanes, and that creating this
category may be unnecessary. For this reason, the FAA is specifically
asking for comments concerning the value of creating a separate, simple
airplane level.
iii. Proposed Sec. 23.10, Accepted Means of Compliance
Proposed Sec. 23.10 would require an applicant to show the FAA how
it would demonstrate compliance with this part using a means of
compliance, which may include consensus standards, accepted by the
Administrator. Proposed Sec. 23.10 would also require an applicant
requesting acceptance of a means of compliance to provide the means of
compliance to the FAA in a form and manner specified by the
Administrator.
Proposed Sec. 23.10 would create flexibility for applicants in
developing means of compliance and also specifically identify consensus
standards as a means of compliance the Administratory may find
acceptable. The Part 23 Reorganization ARC proposed using consensus
standards for the detailed means of compliance to the fundamental
safety requirements in proposed part 23. As discussed in the
International Harmonization Efforts section of this NPRM, the intent of
this proposal is to create a regulatory architecture for part 23 that
is agile enough to keep up with innovation. Allowing the use of
consensus standards would accomplish this goal.
The Part 23 Reorganization ARC recommended creating this proposed
section to identify specifically the means of compliance documents
developed by industry, users such as large flight schools, the
interested public, and the FAA, that an applicant could use in
developing a certification application. The ARC expressed two concerns
that led to the creation of the proposed requirement. First, applicants
need to use a means of compliance accepted by the Administrator when
showing compliance to part 23. Second, while a consensus standards body
(i.e., ASTM, SAE, RTCA, etc.) developed means of compliance document
may be available, individuals or organizations may also submit their
own means of compliance documentation to the Administrator for
consideration and potential acceptance. Additionally, the FAA wants to
ensure applicants understand that an applicant-developed means of
compliance document would require FAA review and acceptance by the
Administrator.
The FAA anticipates that individuals or organizations would develop
acceptable means for complying with the proposed performance standards.
A standards organization such as ASTM, for example, could generate a
series of consensus-based standards for review, acceptance, and public
notice of acceptance by the FAA. The ASTM standards could be one way,
but not the only way, to demonstrate compliance with part 23. Other
consensus standard bodies such as RTCA and SAE are currently focused on
developing standards for aircraft components and appliances.
The proposed airworthiness standards would allow airplanes to be
certificated at different airplane certification levels. For example,
software integrity levels appropriate for a certification level 1
airplane may not be appropriate for a certification level 4 airplane.
Additionally, the takeoff performance of an airplane might be evaluated
differently for an airplane intended to be certificated at different
airplane certification levels. An applicant seeking certification of a
certification level 1 airplane with a takeoff distance of 200 feet, for
example, would not need to establish the takeoff distance with the same
degree of accuracy as would an applicant seeking certification of a
certification level 4 high-speed airplane with a takeoff distance of
4,000 feet.
By using means of compliance documents to show compliance with the
proposed performance-based rules, the need for special conditions, ELOS
[[Page 13466]]
findings, and exemptions to address new technology advancements would
diminish. Once the Administrator accepted a means of compliance, it may
be used for future applications for certification unless formally
rescinded. Allowing the use of consensus standards as a means of
compliance to performance-based regulations would provide the FAA with
the agility necessary to more rapidly accept new technology, leverage
industry expectations in the development of new means of compliance
documents, and provide for the use of harmonized means of compliance
among the FAA, industry, and foreign CAAs. While an applicant would not
be required to use previously accepted means of compliance documents,
their use would streamline the certification process by eliminating the
need to develop an issue paper to address the certification of new
technology. Proposed AC 23.10,\19\ Accepted Means of Compliance, would
provide guidance for applicants on the process applicants would follow
to submit proposed means of compliance to the FAA for consideration by
the Administrator.
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\19\ See www.regulations.gov (Docket # FAA-2015-1621).
---------------------------------------------------------------------------
The Part 23 Reorganization ARC expressed concerns that a consensus
standard could be biased in favor of a few large manufacturers and
would create an unfair competitive advantage. The FAA notes that any
interested party may participate in the ASTM committees developing
consensus standards thereby, mitigating this concern. The FAA expects
that other consensus standards bodies would allow similar opportunities
for interested parties to participate in their standards development
work. Additionally, any individual or organization could develop its
own means of compliance and submit it to the FAA for acceptance by the
Administrator. The other risk identified by the Part 23 Reorganization
ARC was that specialists in the industry could argue for complex means
of compliance when the FAA would accept a simpler or more cost
effective approach. However, the FAA would continue to allow applicants
to propose their own means of compliance when the larger industry
standard may be the appropriate level of safety for one, but not all
certification levels. Lastly, the FAA intends to continue to allow the
use of the current prescriptive means of compliance contained in
current part 23 requirements as one obvious alternative to showing
compliance with proposed part 23. This would not apply to the proposed
sections that contain new requirements, such as Sec. Sec. 23.200,
23.215, and 23.230.
The Part 23 Reorganization ARC also was aware the Administrator has
accepted various manufacturers' internal standards in the past and
recommended having that option stated in the proposal. Proposed Sec.
23.10 would allow applicants to submit their internal standards as
means of compliance for consideration by the Administrator.
iv. Removal of Subpart A Current Regulations
The FAA proposes removing current Sec. 23.2, Special retroactive
requirements, from part 23 because the operational rules currently
address these requirements. The current retroactive rule is more
appropriate in the operating rules. The FAA proposes amending 14 CFR
part 91, as discussed later in the Discussion of the Proposed
Regulatory Amendments to ensure removing the current Sec. 23.2
requirement would not affect the existing fleet.
2. Subpart B--Flight
a. General Discussion
The FAA proposes moving away from the current stall characteristics
and spin testing approach to address the largest cause of fatal
accidents in small airplanes. Proposed Sec. 23.215 in subpart B would
omit the one turn/three second spin requirement for normal category
airplanes, but it would increase the stall handling characteristics and
stall warning requirements so the airplane would be substantially more
resistant to stall-based departures than the current rules require.
The FAA also proposes eliminating the utility, acrobatic, and
commuter categories in part 23. Accordingly, a new airplane would have
to be approved for aerobatic loads as the normal category, even if an
applicant only wanted to spin the airplane. Therefore, the FAA proposes
to restrict certification of new airplanes for dual use, which can be
done today using both the normal and utility categories. The FAA
believes that if the airplane can spin for spin training, then the
airplane can inadvertently stall and depart into a spin during normal
operations. One of the FAA's goals is to prevent inadvertent stalls, so
allowing airplanes that are commonly used as rental airplanes to spin
would defeat the goal. However, the FAA would consider accepting a
dual-purpose airplane if the airplane manufacturer provided a system
that could be changed mechanically or electronically from normal to
aerobatic as a maintenance function rather than controlled by the
pilot.
The FAA proposes consolidating the performance requirements for
high-speed multiengine airplanes and multiengine airplanes that weigh
over 12,500 pounds. These airplanes are currently required to meet a
series of one-engine-inoperative climb gradients. These climb gradients
were based on part 25 requirements and intended for commuter category
airplanes used in scheduled air service under parts 135 and 121. New
airplanes certificated under part 23 are not eligible for operation in
scheduled service under part 121, diminishing the utility of the
commuter category for these airplanes.
More recently, part 23 multiengine jets intended to be used under
parts 91 or 135 have been certificated in the commuter category, using
part 25 based climb gradient requirements. In the spirit of the
proposed rule change, the FAA has decided that the one-engine-
inoperative climb requirements would be independent of the number of
engines and some of the original requirements would be consolidated
into a single requirement that would require performance very close to
what is required today. This action intends to maintain the performance
capabilities expected in 14 CFR part 135 operations.
The FAA proposes changes in the flight characteristics rules to
keep the safety intent of the existing requirements consistent with the
other proposed part 23 sections. The current part 23 requirements are
based on small airplanes, designed with reversible controls, which
include some accommodations for stability augmentation and autopilots.
The FAA believes the proposed language would capture the current
requirements for flight characteristics and allows for varying degrees
of automated flight control systems in the future.
Finally, the FAA proposes adding a requirement to require
certification levels 1 and 2 multiengine airplanes, not capable of
climbing after a critical loss of thrust, to stall prior to reaching
the minimum directional control speed (VMC).
b. Specific Discussion of Changes
i. Proposed Sec. 23.100, Weight and Center of Gravity
Proposed Sec. 23.100 would require an applicant to determine
weights and centers of gravity that provide limits for the safe
operation of the airplane. Additionally, it would require an applicant
to show compliance with each requirement of this subpart at each
combination of weight and center of
[[Page 13467]]
gravity within the airplane's range of loading conditions using
tolerances acceptable to the Administrator. Proposed Sec. 23.100 would
also require the condition of the airplane at the time of determining
its empty weight and center of gravity to be well defined and easily
repeatable.
Proposed Sec. 23.100 would capture the safety intent of current
Sec. Sec. 23.21, Proof of compliance; 23.23, Load distribution limits;
23.25, Weight limits; 23.29, Empty weight and corresponding center of
gravity; and 23.31, Removable ballast. This proposed section would
ensure an applicant considers the important weight and balance
configurations that influence performance, stability, and control when
showing compliance with the flight requirements. The main safety
requirements of current Sec. Sec. 23.21-23.31 are located in current
Sec. Sec. 23.21 and 23.23. Current Sec. 23.21 allows for a range of
loading conditions shown by test or systematic investigation. The
proposed rule would still allow for this flexibility, including the
tolerances for flight test. Sections 23.25-23.31 provide definitions
and directions for determining weights and centers of gravity and
provides directions for informing the pilot. For these reasons, the
information in these sections is more appropriate as a means of
compliance.
ii. Proposed Sec. 23.105, Performance
Proposed Sec. 23.105 would require an airplane to meet the
performance requirements of this subpart in various conditions based on
the airplane's certification and performance levels for which
certification is requested. Proposed Sec. 23.105 also would require an
applicant to develop the performance data required by this subpart for
various conditions, while also accounting for losses due to atmospheric
conditions, cooling needs, and other demands on power sources. Finally,
proposed Sec. 23.105 would require the procedures used for determining
takeoff and landing distances to be executed consistently by pilots of
average skill in atmospheric conditions expected to be encountered in
service.
Proposed Sec. 23.105 would capture the safety intent of current
Sec. 23.45, Performance--General. The safety intent of Sec. 23.45(a)
is captured in proposed Sec. 23.105(a) and is essentially unchanged
from the current rule, except to incorporate the proposed certification
levels and speed divisions.
Proposed Sec. 23.105(b) would capture the safety intent of Sec.
23.45(b) by retaining Sec. 23.45(b)(1) requirements and combining
Sec. 23.45(b)(2) and (b)(3) and allowing all airplanes to use the
cooling climb limits as their upper temperature. The level of safety
remains the same as the current part 23 because part 23 airplane pilots
only have the limitations identified in the airplane flight manual,
including engine temperature limits.
Proposed Sec. 23.105(c) would also capture the safety intent of
Sec. 23.45(f). The safety intent of the current rule is to ensure an
average pilot can consistently get the same results as published in the
Airplane Flight Manual (AFM). The FAA believes this requirement would
ensure applicants either perform their performance tests in a
conservative manner or add margins and procedures to the AFM
performance section so an average pilot can achieve the same
performance.
Proposed Sec. 23.105(d) would require performance data to account
for losses due to atmospheric conditions, cooling needs, and other
demands. The current rule specifies the position of cowl flaps or other
means for controlling the engine air supply. The proposed language
accounts for airplane performance, if affected by the cooling needs of
the propulsion system, which is the safety intent of Sec. 23.45, but
would omit the details because they are more appropriate as a means of
compliance.
Proposed Sec. 23.105(d) would also capture the safety intent Sec.
23.45(d) and (e). The safety intent of the current rule is to ensure
the airplane performance accounts for minimum power available from the
propulsion system, considering atmospheric and cooling conditions and
accessories requiring power.
iii. Proposed Sec. 23.110, Stall Speed
Proposed Sec. 23.110 would require an applicant to determine the
airplane stall speed or the minimum steady flight speed for each flight
configuration used in normal operations, accounting for the most
adverse conditions for each flight configuration, with power set at
idle or zero thrust.
Proposed Sec. 23.110 would capture the safety intent of current
Sec. 23.49, Stalling speed. Stall speeds are necessary to define
operating and limiting speeds used to determine airplane performance.
They also provide a basis for determining kinetic energy in emergency
landing conditions. Therefore, determining stall speeds is required in
the configurations used in the operation of the airplane.
The FAA proposes removing the 61-knot stall speed division for
single-engine airplanes from the rules because this speed has not been
a limitation since 1992 with the addition of the options for stall
speeds in excess of 61 knots in Sec. 23.562, Emergency landing dynamic
conditions. Therefore, the 61-knot stall speed is a technical division
rather than a limitation and would be more appropriate as a means of
compliance.
The FAA is changing its approach to crashworthiness. Instead of
constraining the connection between stall speed and crashworthiness to
a single fixed speed, the FAA proposes allowing alternative approaches
to crashworthiness. The intent is to encourage incorporation of
innovations from other industries to provide more occupant protection
in the airframe. This approach would base occupant protection on the
actual stall speed rather than a single mandated stall speed.
iv. Proposed Sec. 23.115, Takeoff Performance
Proposed Sec. 23.115 would require an applicant to determine
airplane takeoff performance, which includes the determination of
ground roll and initial climb distance to 50 feet, accounting for stall
speed safety margins, minimum control speeds; and climb gradients.
Proposed Sec. 23.115 would also require the takeoff performance
determination to include accelerate-stop, ground roll and initial climb
to 50 feet, and net takeoff flight path, after a sudden critical loss
of thrust for certification levels 1, 2, and 3 high-speed multiengine
airplanes, multiengine airplanes with a maximum takeoff weight greater
than 12,500 pounds, and certification level 4 multiengine airplanes.
Proposed Sec. 23.115 would capture the safety intent of current
Sec. Sec. 23.51, Takeoff speeds; and 23.61, Takeoff flight path.
Takeoff distance information and the associated procedures for
achieving those distances are necessary for the safe operation of all
airplanes certified under part 23. Proposed Sec. 23.115 would require
applicants to determine, develop, and publish distance and procedure
data for the pilot to use. The effects of airplane weight, field
temperature and elevation, winds, runway gradient, and runway surface
also need to be available to the pilot because they affect airplane
performance. For proposed simple entry-level airplanes, conservative
analysis may supplement flight test while data for larger, higher
performance airplanes are expected to provide the level of precision
that is accepted today.
Additionally, proposed Sec. 23.115 would require applicants to
determine critical thrust loss cases for multiengine airplanes. Today,
the loss of one engine on a two-engine airplane is the standard model.
The future possibilities for the functions of engines, if different
from
[[Page 13468]]
thrust, and how the engines are controlled, may determine critical
thrust loss. For example, a large number of engines along the leading
edge of a wing could function as a high-lift device as well as provide
thrust.
Historically, limited propulsion options and the need for inherent
stability from reversible, mechanical control systems have restrained
airplane configurations. The FAA anticipates that new propulsion
systems and affordable electronic flight control systems will challenge
these traditional designs and need alternative means of compliance.
Speed multiples and factors used in current part 23 prescriptive
requirements are based on traditional airplane configurations. Part 23
mandates these details of design for compliance. The FAA believes
removing these details would provide applicants with the agility and
flexibility to address these new airplane configurations. The current
factors will still apply for traditional configurations, but proposed
performance-based requirements should allow rapid adoption of new means
of compliance for future airplane configurations.
The FAA proposes removing airplane categories and weight and
propulsion certification divisions for multiengine jets over 6,000
pounds and replacing them with divisions based on risk and performance.
The commuter category, originally intended for the certification of
airplanes over 12,500 pounds and up to 19 passengers, is currently used
for larger business jets with less than ten passengers. The FAA
proposes that high-speed, multiengine and multiengine airplanes over
12,500 pounds should continue meeting the equivalent commuter category
performance-based requirements. The historical assumption applied to
jets was that they were fast, had high wing loadings, and used
significant runway distances for takeoff and landing. Therefore, all
jets were required to have guaranteed climb performance with one engine
inoperative. This requirement does not currently apply to single engine
jets. The proposed performance requirements would be based on number of
passengers (certification level) and airplane performance (performance
level), not weight or propulsion type. The proposed certification and
performance levels approach would not offer a one-to-one relationship
with the current requirements. A low-speed turbine-powered airplane may
be more appropriately addressed by regulations currently applicable to
piston-powered airplanes, while a piston-powered or a high-speed
electric airplane may be more appropriately addressed by regulations
currently used for the certification of turbine-powered airplanes. The
proposed certification and performance level approach, while different
from the current divisions, would capture the safety intent of part 23
more appropriately than the current propulsion and weight divisions.
v. Proposed Sec. 23.120, Climb Requirements
Proposed Sec. 23.120 would require an applicant to demonstrate
various minimum climb performances out of ground effect, depending on
the airplane's certification level, engines, and performance
capability. This new provision would capture the safety intent of
current Sec. Sec. 23.65, Climb: All engines operating; 23.67, Climb:
One engine inoperative; and 23.77, Balked landing. Minimum climb
performance information is necessary so pilots can determine if they
have adequate clearance from obstacles beyond the end of the runway.
New engine technologies, especially electric, would allow for
alternative configurations that would invalidate many of the detailed
test configuration and power assumptions that are in the current
requirements.
Part 23 currently has a large matrix for all the climb requirements
that includes category, weight, and number of engines, resulting in
over 20 different climb gradient requirements. This reflects the growth
in the variety of different airplane types that has occurred since the
certification regulations were first adopted in CAR 3. Because the FAA
proposes simplifying these divisions using certification levels and
airplane performance levels, it can eliminate required climb gradients
for three and four engines. The FAA proposes basing multiengine climb
gradients on critical loss for thrust and using the gradient for the
current twin-engine airplanes because it has resulted in a safe service
history. The FAA proposes replacing the term ``failure of the critical
engine'' (which addresses a twin engine airplane) with ``critical loss
of thrust'' for airplanes certificated under those provisions. The
reason for replacing this term is that with configurations utilizing
large numbers of engines, the failure modes may not follow the
traditional failure modes as with the loss of one engine on a two-
engine airplane. Furthermore, the FAA proposes retaining and
consolidating the climb gradients from current Sec. 23.67 because
these gradients are important minimum performance requirements for
maintaining the current level of safety.
Proposed Sec. 23.120(a) would capture the safety intent of current
Sec. 23.65. It would retain the existing climb gradients and
atmospheric conditions required for pilot planning.
Proposed Sec. 23.120(b) would capture the safety intent of current
Sec. 23.67, and consolidates the weight and propulsion divisions into
all engines operating, critical loss of thrust, and balked landing
groups. Furthermore, for high-speed airplanes, after a critical loss of
thrust, the FAA proposes reducing the number of required climb
conditions for certification to one gradient at 400 feet (122 meters)
above the takeoff surface. For the typical part 23 certified twin-
engine airplane, the required climb gradient at 400 feet (122 meters)
above the takeoff surface is generally the most challenging. Airplanes
that have the performance to meet this one requirement typically can
meet all the current requirements. For certification levels 3 and 4,
high-speed multiengine airplanes, the FAA proposes consolidating the
configurations currently prescribed for the second segment climb and a
discontinued approach. The climb gradient difference between these
segments is 0.1 percent and uses the takeoff flap configuration rather
than the approach flap configuration. Requiring only one climb gradient
at 400 feet (122 meters) above the takeoff surface with the landing
gear retracted and flaps in the approach position would maintain the
current level of safety while reducing the requirements by eliminating
initial, final, and discontinued approach climb tests. Because the
proposed requirements would reduce the amount of climb testing for
designs intended for use under part 91, applicants would also need to
provide the traditional operational performance data, as is currently
done, if the design is intended to be used for commercial operations
under part 135 operating rules.
The FAA also proposes to normalize the initial climb height to 50
feet (15 meters) above the takeoff surface. The regulations for the
certification of commuter category airplanes essentially adopted many
of the part 25 climb requirements, including an initial climb height of
35 feet (11 meters) above the takeoff surface. When the commuter
category was adopted, the expectation was that these airplanes would be
used in part 121 service. This expectation allowed the FAA to accept
the part 25 assumption that takeoff distances would be factored; thus,
providing a safety margin to offset the lower initial climb height.
Part 23 requirements provide minimum safe operations for part 91, which
does not require factored takeoff
[[Page 13469]]
distances. Therefore, allowing a 35 foot (11 meters) height above the
takeoff surface is a lower safety margin than used for smaller
airplanes and, for this reason, the FAA proposes to make all airplanes
certificated under part 23 use 50 feet (15 meters) above the takeoff
surface.
vi. Proposed Sec. 23.125, Climb Information
Proposed Sec. 23.125 would require an applicant to determine the
climb performance for--
All single engine airplanes;
Certification level 3 multiengine airplanes after a
critical loss of thrust on takeoff in the initial climb configuration;
and
All multiengine airplanes during the enroute phase of
flight with all engines operating and after a critical loss of thrust
in the cruise configuration.
Proposed Sec. 23.125 would also require an applicant to determine
the glide performance of the airplane after a complete loss of thrust
for single engine airplanes.
Proposed Sec. 23.125 would capture the safety intent of current
Sec. Sec. 23.63, Climb: General; 23.66, Takeoff climb: One-engine
inoperative; 23.69, Enroute climb/descent; and 23.71, Glide: Single-
engine airplanes. The intent of these requirements is to provide pilots
with climb and glide performance data that is important for safety,
especially in conditions near the performance limits of the airplane.
Sections 23.63, 23.66, and 23.69 are not minimum performance sections,
but contain information used in the development of the AFM. Proposed
Sec. 23.125 would require an applicant to determine climb performance.
The performance data determination provides a good example of how the
use of certification levels can allow simplified approaches to meet
applicable airworthiness requirements for simple, and levels 1 and 2
airplanes.
vii. Proposed Sec. 23.130, Landing
Proposed Sec. 23.130 would require an applicant to determine the
landing distance for standard temperatures at each weight and altitude
within the operational limits for landing. The landing distance
determination would start from a height of 50 feet (15 meters) above
the landing surface, require the airplane to land and come to a stop
(or for water operations, reach a speed of 3 knots) using approach and
landing speeds, configurations, and procedures, which allow a pilot of
average skill to meet the landing distance consistently and without
causing damage or injury. Proposed Sec. 23.130 would require these
determinations for standard temperatures at each weight and altitude
within the operational limits for landing.
Proposed Sec. 23.130 would capture the safety intent of current
Sec. 23.73, Reference landing approach speed, and Sec. 23.75, Landing
Distance. Landing distance information and the associated procedures
for achieving those distances are necessary to prevent runway overruns.
Applicants would be required to determine, develop, and publish
distance and procedures data for use in pilot planning. Proposed Sec.
23.130 would combine the current requirements to determine approach
speed and landing distance because a determination of both is required
for a landing distance determination.
viii. Proposed Sec. 23.200, Controllability
Proposed Sec. 23.200 would require the airplane to be controllable
and maneuverable, without requiring exceptional piloting skill,
alertness, or strength, within the operating envelope, at all loading
conditions for which certification is requested. This would would
include during low-speed operations, including stalls, with any
probable flight control or propulsion system failure, and during
configuration changes. Proposed Sec. 23.200 would require the airplane
to be able to complete a landing without causing damage or serious
injury, in the landing configuration at a speed of VREF
minus 5 knots using the approach gradient equal to the steepest used in
the landing distance determination. Proposed Sec. 23.200 would require
VMC not to exceed VS1 or VS0 for all
practical weights and configurations within the operating envelope of
the airplane for certification levels 1 and 2 multiengine airplanes
that cannot climb after a critical loss of thrust. Proposed Sec.
23.200 would also require an applicant to demonstrate those aerobatic
maneuvers for which certification is requested and determine entry
speeds.
Proposed Sec. 23.200 would capture the safety intent of Sec. Sec.
23.141, Flight Characteristics--General, 23.143, Controllability and
Maneuverability--General; 23.145, Longitudinal control; 23.147
Directional and lateral control; 23.149, Minimum control speed; 23.151,
Acrobatic maneuvers; 23.153, Control during landing; 23.155, Elevator
control force in maneuvers; 23.157, Rate of roll; 23.697(b) and (c),
Wing flap controls. Proposed Sec. 23.200 would ensure the maneuvering
flight characteristics of the airplane are safe and predictable
throughout the flight envelope and result in repeatable, smooth
transitions between turns, climbs, descents, and level flight.
Configuration changes, such as flap extension and retraction, landing
gear extension and retraction, and spoiler extension and retraction,
along with probable failures resulting in asymmetric thrust, would also
have to result in safe, controllable, and predictable characteristics.
Proposed Sec. 23.200(a) and (b) would capture the safety intent of
Sec. Sec. 23.143, Controllability and Maneuverability--General;
23.145, Longitudinal control; 23.147, Directional and lateral control;
23.149, Minimum control speed; 23.151, Acrobatic maneuvers; 23.153,
Control during landings; 23.155, Elevator control force in maneuvers;
and 23.157, Rate of roll. The FAA proposes limiting the requirements
for practical loadings and operating altitudes without the use of
exceptional piloting skill, alertness, or strength.
Current part 23 provides prescriptive and detailed test
requirements based on specific airplane configurations. Additionally,
the current rules include flight test procedures that are based on
traditional reversible controls and engine locations that are, in some
cases, derived from airplanes designed in the 1930's. The FAA proposes
performance-based requirements that would remain applicable to
traditionally designed airplanes, but allow alternative approaches to
showing compliance based on new configurations, flight control systems,
engine locations, and number of engines.
Proposed Sec. 23.200(c) would require all certification levels 1
and 2 multiengine airplanes that lack the performance to climb after a
critical loss of thrust to stall before loss of directional control.
This is a new requirement and it targets the high number of fatal
accidents that occur after an engine failure in this class of airplane.
Light multiengine airplanes that lack the performance to climb after
the critical loss of thrust are especially susceptible to this type of
accident. The Part 23 Reorganization ARC discussed and several members
proposed that all multiengine airplanes have guaranteed climb
performance after a critical loss of thrust. Ultimately, this approach
was rejected, as it could impose a significant cost on the production
of training airplanes. Furthermore, several members pointed out that
the safety concern was not that the airplane could not climb on one
engine, but rather that the airplane would depart controlled flight at
low speeds above stall as a result of asymmetric thrust. The FAA agrees
that loss of control caused by asymmetric thrust is the critical safety
issue that should be addressed and the FAA believes that the proposed
rule responds to this concern.
[[Page 13470]]
The FAA recognizes concerns regarding the proposed requirement--if
the airplane is allowed to stall, the asymmetric thrust will still
cause the airplane to lose directional control and likely depart
controlled flight. The FAA agrees, but believes that pilots are
typically more aware of their stall speeds than minimum control speed,
especially during turns. Furthermore, these airplanes would be required
to meet the proposed stall warning and stall characteristic
requirements, which the FAA expects would provide additional safety
margins beyond current requirements. Finally, the system that provides
stall warning could also be designed to provide VMC warning.
ix. Proposed Sec. 23.205, Trim
Proposed Sec. 23.205 would require the airplane to maintain
longitudinal, lateral, and directional trim under various conditions,
depending on the airplane's certification level, without allowing
residual forces to fatigue or distract the pilot during likely
emergency operations, including a critical loss of thrust on
multiengine airplanes.
Proposed Sec. 23.205 would capture the safety intent of current
Sec. 23.161, Trim. Section 23.161(a) addresses the safety intent while
paragraphs (b), (c), (d), and (e) provide prescriptive details on how
to do flight testing for traditionally configured airplanes and are
more appropriate for inclusion in means of compliance.
x. Proposed Sec. 23.210, Stability
Proposed Sec. 23.210 would require airplanes not certified for
aerobatics to have static and dynamic longitudinal, lateral, and
directional stability in normal operations, and provide stable control
force feedback throughout the operating envelope. Proposed Sec. 23.210
would also preclude any airplane from exhibiting any divergent
stability characteristic so unstable as to increase the pilot's
workload or otherwise endanger the airplane and its occupants.
Proposed Sec. 23.210 would capture the safety intent of the
current Sec. Sec. 23.171, Stability--General; 23.173, Static
longitudinal stability; 23.175, demonstration of static longitudinal
stability; 23.177, Static directional and lateral stability; 23.179,
Instrumented stick force measurements; and 23.181, Dynamic stability.
The current requirements have their origins in Aeronautics Bulletin 7,
amendment 7a, effective October 1, 1934, which predates CAR 3. These
airplane handling quality and stability requirements were based on the
technology associated with simple mechanical control systems and what
was considered acceptable on existing airplanes of the time. Although
many of these requirements are still appropriate for traditional flight
control systems, they do not take into account the capabilities of new
computer-based flight control systems. The FAA recognizes the
availability of hybrid reversible and automated flight control systems
and proposes performance-based language that would allow their
installation in part 23 certificated airplanes without the use of
special conditions, while still maintaining adequate requirements for
reversible controls. The intent is to facilitate the use of systems
that may enhance safety while reducing pilot workload.
xi. Proposed Sec. 23.215, Stall Characteristics, Stall Warning, and
Spins
Proposed Sec. 23.215 would require an airplane to have
controllable stall characteristics in straight flight, turning flight,
and accelerated turning flight with a clear and distinctive stall
warning that would provide sufficient margin to prevent inadvertent
stalling. Proposed Sec. 23.215 would allow for alternative approaches
to meeting this requirement for certification levels 1 and 2 airplanes
and certification level 3 single-engine airplanes, not certified for
aerobatics, in order to avoid a tendency to inadvertently depart
controlled flight. Proposed Sec. 23.215 would require airplanes
certified for aerobatics to have controllable stall characteristics and
the ability to recover within one and one-half additional turns after
initiation of the first control action from any point in a spin.
Additionally, the airplane would not be allowed to exceed six turns or
any greater number of turns for which certification is requested while
remaining within the operating limitations of the airplane. Proposed
Sec. 23.215 would preclude airplanes certified for aerobatics from
having spin characteristics that would result in unrecoverable spins
due to pilot disorientation or incapacitation or any use of the flight
or engine power controls.
Proposed Sec. 23.215 would capture the safety intent of current
Sec. Sec. 23.201, Wings level stall; 23.203, Turning flight and
accelerated turning stalls; 23.207, Stall warning; and 23.221,
Spinning. Historically, the FAA focused its requirements on the ability
of the airplane to recover from a one-turn or three-second spin more
than on the stall characteristics of the airplane. From the first fatal
stall accident in the Wright Flyer airplane to today's fatal stall
accidents, the number one cause in small airplanes is a departure from
controlled flight following an inadvertent stall.
Except for accidental departures from controlled flight during
stall training, most of these inadvertent departures occur in close
proximity to the ground, and because of this, the current requirement
to recover from a one-turn or three-second spin may not be the best
method to assess the safety of the airplane. Even an experienced pilot
may not have enough altitude to recover from the spin before impacting
the ground. For this reason, the FAA proposes to delete the one-turn/
three-second spin recovery requirement for normal category airplanes.
Instead, the FAA proposes to increase the stall characteristics
requirements by requiring that all certification levels 1 and 2
airplanes and certification level 3 single-engine airplanes provide
substantial departure resistance to prevent inadvertent stalls from
resulting in a departure from controlled flight and becoming fatal
accidents.
Accident studies show that even hitting the ground as a result of a
stall can be survivable if the airplane is still in controlled flight.
Conversely, impacting the ground out of control is typically fatal. The
FAA envisions numerous alternative approaches to meeting the proposed
requirements, ranging from one extreme of spin resistance to the other
extreme of a total systems-based approach such as stick pusher.
Furthermore, there are envelope protection systems and stall warning
concepts that could also be considered when assessing departure
resistance. The possible approaches to meeting the proposed
requirements are so broad that these alternatives would be better
addressed in means of compliance. This level of protection may vary
based on the characteristics of the airplane, but the FAA expects this
change in design philosophy would increase the level of protection
designed into airplanes under this proposed rule. Certification level 3
multiengine airplanes and certification level 4 airplanes historically
have not had a large number of departure-related accidents. While the
FAA encourages manufacturers to consider designing departure resistance
into these airplanes, the FAA does not propose adding a new requirement
for certification level 3 multiengine airplanes and certification level
4 airplanes.
The FAA also proposes revising stall warning requirements by
removing prescriptive speed based stall warning requirements and
requiring a clear and distinctive warning with sufficient
[[Page 13471]]
warning margin for the pilot to prevent a stall. Historically, stall
warning systems in part 23 airplanes have been simple, mechanical vanes
that may or may not provide reasonable lead-time to prevent a stall.
These systems also can provide false alerts when they are not needed,
creating a nuisance. Furthermore, similar sounding warning horns that
alert the pilot of other situations can result in the pilot either
becoming used to the warning sounds or mistaking the stall warning for
another warning such as the autopilot disconnect horn. The FAA believes
removing the current prescriptive speed based stall warning from the
rules would encourage the installation of better, more effective low
speed awareness systems that may use angle of attack, a speed decay
rate, or clear voice commands to alert the pilot.
xii. Proposed Sec. 23.220, Ground and Water Handling Characteristics
Proposed Sec. 23.220 would require airplanes intended for
operation on land or water to have controllable longitudinal, and
directional handling characteristics during taxi, takeoff, and landing
operations. Proposed Sec. 23.220 would also require an applicant to
establish a maximum wave height shown to provide for controllable
longitudinal, and directional handling characteristics and any
necessary water handling procedures for those airplanes intended for
operation on water.
Proposed Sec. 23.220 would capture the safety intent of Sec. Sec.
23.231, Longitudinal stability and control; 23.233, Directional
stability and control; 23.235, Operation on unpaved surfaces; 23.237,
Operation on water; and 23.239, Spray characteristics.
xiii. Proposed Sec. 23.225, Vibration, Buffeting, and High-Speed
Characteristics
Proposed Sec. 23.225 would preclude vibration and buffeting from
interfering with the control of the airplane or causing fatigue to the
flightcrew, for operations up to VD/MD. Proposed
Sec. 23.225 would allow stall warning buffet within these limits.
Proposed Sec. 23.225 would preclude perceptible buffeting in cruise
configuration at 1g and at any speed up to VMO/
MMO, except stall buffeting for high-speed airplanes and all
airplanes with a maximum operating altitude greater than 25,000 feet
(7,620 meters) pressure altitude. Proposed Sec. 23.225 would require
an applicant seeking certification of a high-speed airplane to
determine the positive maneuvering load factors at which the onset of
perceptible buffet occurs in the cruise configuration within the
operational envelope and preclude likely inadvertent excursions beyond
this boundary from resulting in structural damage. Proposed Sec.
23.225 would also require high-speed airplanes to have recovery
characteristics that do not result in structural damage or loss of
control, beginning at any likely speed up to VMO/
MMO, following an inadvertent speed increase and a high-
speed trim upset.
Proposed Sec. 23.225 would capture the safety intent of current
Sec. Sec. 23.251, Vibration and buffeting; 23.253, High speed
characteristics; and 23.255, Out of trim characteristics. Proposed
Sec. 23.225(a), (b), and (c) would capture the safety of current Sec.
23.251(a), (b), and (c). The current safety intent of Sec. Sec. 23.253
and 23.255 are incorporated in proposed Sec. 23.225(d).
Proposed Sec. 23.225(d)(1) addresses the current language in Sec.
23.253, which indirectly divides the airplanes by engine type rather
than performance. These requirements have typically been applied
automatically to turbine-powered airplanes with the assumption that all
turbine-powered airplanes flew fast and high. Piston or electric
airplanes were not required to meet these requirements even if they
were faster than many turboprops, because of propulsion assumptions in
the past. For this reason, the FAA is amending this requirement to be
based on performance instead of propulsion type using the same high-
speed criteria from other subpart B sections. The existing details
would be removed from the rules, as they are more appropriate as means
of compliance because it would allow for alternatives for non-
traditional airplanes, such as very fast piston airplanes.
Proposed Sec. 23.225(d)(2) would address the current safety intent
in Sec. 23.255 by relying on performance and design characteristics
without discriminating based on propulsion type. The specific design
details are more appropriate as means of compliance.
xiv. Proposed Sec. 23.230, Performance and Flight Characteristics
Requirements for Flight in Icing Conditions
Proposed Sec. 23.230 would require an applicant requesting
certification for flight in icing conditions to demonstrate compliance
with each requirement of this subpart. Exceptions to this rule would be
those applicable to spins and any requirement that would have to be
demonstrated at speeds in excess of 250 KCAS, VMO or
MMO, or a speed that an applicant demonstrates the airframe
would be free of ice accretion. Proposed Sec. 23.230 would require the
stall warning for flight in icing conditions and non-icing conditions
to be the same. Proposed Sec. 23.230 would require an applicant
requesting certification for flight in icing conditions to provide a
means to detect any icing conditions for which certification is not
requested and demonstrate the airplane's ability to avoid or exit those
conditions. Proposed Sec. 23.230 would also require an applicant to
develop an operating limitation to prohibit intentional flight,
including takeoff and landing, into icing conditions for which the
airplane is not certified to operate. Proposed Sec. 23.230 would also
increase safety by adding optional icing conditions a manufacturer may
demonstrate its airplane can either safely operate in, detect and
safely exit, or avoid. Proposed Sec. 23.230 would only apply to
applicants seeking certification for flight in icing.
Proposed Sec. 23.230 would capture the safety intent of the
performance and flight characteristics requirements in current Sec.
23.1419(a) and along with proposed Sec. Sec. 23.940, Powerplant ice
protection, and 23.1405, Flight in icing conditions, and their
respective means of compliance would address NTSB safety
recommendations A-96-54 and A-96-56. Section 23.1419 specifies that
airplanes must be able to operate safely in the icing conditions
identified in appendix C to part 25, which encompass cloud size drops
of less than 100 microns in diameter. Freezing drizzle (i.e., drops up
to 500 microns in diameter) and freezing rain (i.e., drops greater than
500 microns in diameter) icing conditions, which can result in ice
accretion aft of leading edge ice protection systems, are not included
in appendix C to part 25. Amendment 25-140 (79 FR 65507, November 4,
2014) added these icing conditions to appendix O to part 25 and are not
being defined in proposed Sec. 23.230. The FAA believes that the
definitions of these optional icing conditions would be more
appropriate as a means of compliance. The standards for ``capable of
operating safely'' in these conditions would be the same as cloud icing
with additional icing conditions in the takeoff phase.
If certification for flight in the optional freezing drizzle or
freezing rain conditions is not sought, proposed Sec. 23.230 would
require these conditions be avoided or detected and exited safely. The
means of compliance for the latter, detect and exit the situation,
would be similar to current guidance in AC 23.1419-2D, Certification of
Part 23 Airplanes for Flight in Icing Conditions, and is currently
applied during part 23
[[Page 13472]]
airplane icing certifications. These criteria are not as extensive as
recommended by the Part 23 Icing ARC, but the FAA did not want to
impose an additional burden on industry because the service history of
airplanes certified under part 23 and the latest icing regulations at
amendment 23-43 (58 FR 18958, April 9, 1993) show no SLD related
accidents. The FAA believes the safety of the existing fleet can be
greatly increased by improving the freezing drizzle and freezing rain
capability of automated surface weather observation systems and pilot
education and training of the limits of icing certification.
Proposed Sec. 23.230(b) would provide an option to avoid, in lieu
of detecting and exiting, the freezing drizzle or freezing rain icing
conditions for which the airplane is not certified. This option is not
in current guidance and such technology currently does not exist. The
rule would provide an option in the event the technology is developed.
The FAA believes avoiding rather than detecting and exiting would
provide for safer airplane operations and reduce certification costs.
Proposed Sec. 23.230(c) would require an AFM limitation to
prohibit flight in icing conditions for which the airplane is not
certified. This reflects current guidance in AC 23.1419-2D, which most
manufacturers of new part 23 icing certified airplanes follow today. A
minority of new manufacturers are not using AC 23.1419-2D guidance and
have inserted AFM limitation language that reflects Airworthiness
Directives (AD) that were issued globally to pneumatic boot-equipped
airplanes between 1996 and 1998. The ADs in the below table require
immediate exit from severe icing and warn that freezing drizzle and
freezing rain may be conducive to severe icing. The proposed new
limitation is intended to prohibit flight in known icing conditions,
not forecast conditions.
------------------------------------------------------------------------
Airplane model Docket Final rule
------------------------------------------------------------------------
Aerostar Aircraft Corporation Models PA- 97-CE-56-AD 98-04-23
60-600, PA-60-601, PA-60-601P, PA-60-
602P, and PA-60-700P Airplanes.........
Pilatus Britten-Norman Ltd., Models BN- 97-CE-54-AD 98-04-21
2A, BN-2B, and BN-2T Airplanes.........
Pilatus Aircraft Ltd., Models PC-12 and 97-CE-53-AD 98-20-28
PC-12/45 Airplanes.....................
Partenavia Costruzioni Aeronauticas, 97-CE-51-AD 98-04-20
S.p.A. Model P68, AP68TP 300, AP68TP
600 Airplanes..........................
Mitsubishi Heavy Industries, Ltd., MU-2B 96-CE-61-AD 96-25-02
Series Airplanes.......................
Harbin Aircraft Manufacturing Corp., 97-CE-50-AD 98-04-19
Model Y12 IV airplanes.................
Empresa Brasileira de Aeronautica S.A. 96-CE-02-AD 96-09-12
Airplanes. (Embraer) Models EMB-110P1
and EMB-110P2 Airplanes................
Dornier Luftfahrt GmbH, 228 Series 96-CE-04-AD 96-09-14
Airplanes..............................
De Havilland, Inc., DHC-6 Series 96-CE-01-AD 96-09-11
Airplanes..............................
The Cessna Aircraft Company, 208 Series. 96-CE-05-AD 96-09-15
The Cessna Aircraft Company, Model T210R 98-CE-19-AD 98-20-33
airplane...............................
The Cessna Aircraft Company, Models 97-CE-62-AD 98-05-14 R1
T210, P210, P210R airplanes............
The Cessna Aircraft Company Models T303, 97-CE-63-AD 98-04-28
310R, T310R, 335, 340A, 402B, 402C,
404, F406, 414, 414A, 421B, 421C, 425,
and 441 Airplanes......................
Jetstream Aircraft Limited Models 3101 96-CE-07-AD 96-09-17
and 3201 Airplanes.....................
The New Piper Aircraft PA-23, PA-30, PA- 98-CE-77-AD 99-14-01
31, PA-34, PA-39, PA-40, and PA-42
Series Airplanes.......................
The New Piper Aircraft Corporation 97-CE-60-AD 98-04-26
Models PA-46-310P and PA-46-350P
Airplanes..............................
Beech Aircraft Corporation Models 99, 96-CE-03-AD 96-09-13
99A, A99A, B99, C99, B200, B200C, 1900,
1900C, and 1900D Airplanes.............
Raytheon Aircraft Company 200 Series 98-CE-17-AD 98-20-38
Airplanes..............................
Raytheon Aircraft Company Models E55, 97-CE-58-AD 98-04-24
E55A, 58, 58A, 58P, 58PA, 58TC, 58TCA
Airplanes, and 60, 65-B80, 65-B90, 90,
F90, 100, 300, and B300 Series
Airplanes..............................
Raytheon Aircraft Company Model 2000 97-CE-59-AD 98-04-25
Airplanes..............................
AeroSpace Technologies Of Australia Pty 97-CE-49-AD 98-04-18
Ltd., Models N22B and N24A.............
SIAI Marchetti, S.r.1 Models SF600 and 97-CE-64-AD 98-05-15
SF600A Airplanes.......................
SOCATA--Groupe AEROSPATIALE, Model TBM 97-CE-55-AD 98-04-22
700 Airplanes..........................
Twin Commander Aircraft Corporation 97-CE-57-AD 98-20-34
Models 500, 500-A, 500-B, 500-S, 500-U,
520, 560, 560-A, 560-E, 560-F, 680, 680-
E, 680FL(P), 680T, 680V, 680W, 681,
685, 690, 690A, 690B, 690C, 690D, 695,
695A, 695B, and 720 Airplanes..........
Fairchild Aircraft Corporation, SA226 96-CE-06-AD 96-09-16
and SA227 Series Airplanes.............
------------------------------------------------------------------------
Recently, manufacturers of airplanes certificated under part 23
have proposed inhibiting, or optimizing, bleed air ice protection
systems above an altitude of 30,000 feet (9,144 meters) because the
icing conditions defined in the appendix C to part 25 are limited to
below this altitude. The FAA believes ice protection design at high
altitude should be addressed as a means of compliance and not in the
proposed rule due to various acceptable design solutions. An industry
means of compliance would negate the need for a special condition or
means of compliance issue paper currently required for these projects.
xv. Current Subpart B Regulations Relocated to Other Proposed Subparts
The FAA proposes addressing the safety intent of Sec. 23.33,
Propeller speed and pitch limits, in Sec. 23.900(a) of the propulsion
rules. Additionally, the first part of the current Sec. 23.251(a) that
addresses structural damage has been relocated and is now addressed
under ``flutter'' in proposed subpart C to part 23.
The FAA proposes adopting the Part 23 Icing and Part 23
Reorganization ARC's recommendations to move performance and flight
characteristics requirements in icing, currently in Sec. 23.1419, to
subpart B, so that proposed Sec. 23.1405 only contains systems
requirements. Proposed Sec. 23.230(a) would also include stall warning
requirements. Current guidance contains these stall warning
recommendations (i.e., margin and type of stall) and service history
shows them to be necessary for safe flight in icing conditions. The
exceptions for spin and high-speed requirements are consistent with the
current rule and industry practice that have shown to provide an
adequate level of safety in icing conditions. The FAA determined that
the evaluations of ice contaminated tailplane stall susceptibility,
lateral control in icing, and autopilot operation in icing, which are
included in current guidance for part 23 icing certification,
[[Page 13473]]
are more appropriately addressed as a means of compliance.
xvi. Removal of Subpart B Current Regulations
The FAA proposes removing Sec. 23.45(g) that requires takeoff and
landing distances be determined on a smooth, dry, hard-surfaced runway.
The FAA believes that most performance tests would be done on smooth,
dry, hard-surfaced runways because these surfaces provide applicants
with the best results. Performance determinations on surfaces other
than smooth, dry hard surfaces would provide conservative results and
be acceptable as long as the surface was specified in the AFM.
Therefore, the FAA believes retaining this requirement is unnecessary.
The FAA proposes removing Sec. 23.63, Climb: General, which
addresses the general climb requirements, because the safety intent
contained in this section is redundant with the safety intent proposed
in Sec. 23.125 and the testing procedures contained in Sec. 23.63 are
more appropriate for inclusion in means of compliance.
The FAA proposes removing current Sec. 23.221(a) and (b), which
address spinning requirements for normal and utility category
airplanes, and would no longer be necessary. The increased focus on
preventing stall-based departures along with improved stall margin
awareness would provide a level of safety higher than would be achieved
through spin testing.
The FAA proposes removing the reference to appendix C to part 25,
part II, currently in Sec. 23.1419, Ice protection, paragraph (a),
when relocating Sec. 23.1419 to proposed Sec. 23.230 and 23.1405.
Part II is a means of compliance for determining critical ice
accretions on transport category airplanes and is not applicable to
airplanes certified under part 23.
3. Subpart C--Structures
a. General Discussion
The FAA's intent in proposed subpart C is to provide a regulatory
framework that maintains the current level of safety while (1) allowing
for certification of unique airplane configurations with new technology
and materials, and (2) supporting new means of compliance, testing, and
analysis. To support new technologies, the FAA proposes to incorporate
the safety intent of recent special conditions for airplanes equipped
with systems that affect structural performance, such as load
alleviation systems, in proposed Sec. 23.305. To support new means of
compliance, the FAA proposes in Sec. 23.600 to emphasize a holistic
approach to occupant safety, which would allow certain applicants to
omit current required dynamic seat testing.
It is not the FAA's intent to reduce the level of safety in the
proposed subpart C. The FAA based the prescriptive requirements in
current subparts C and D on service history, historic test data, and
lessons learned. These requirements have provided a level of safety
where structural failure is rare and most often attributable to
airplane upset or pilot disorientation in instrument meteorological
conditions. A means of compliance to proposed subpart C must maintain
the level of safety provided by the current regulations. Applicants
would need to substantiate the level of safety for proposed means of
compliance that deviate from the prescriptive regulations.
Proposed subpart C would replace current subpart C and include
those sections of current subpart D that are applicable to the
airframe. We have arranged proposed subpart C into the following five
topics:
General: Including Sec. 23.300, Structural design
envelope; and Sec. 23.305 Interaction of systems and structures.
Structural Loads: Including Sec. 23.310, Structural
design loads; Sec. 23.315, Flight load conditions; Sec. 23.320,
Ground and water load conditions; Sec. 23.325, Component loading
conditions; and Sec. 23.330, Limit and ultimate loads.
Structural performance: Including Sec. 23.400,
Structural strength; Sec. 23.405, Structural durability; and Sec.
23.410, Aeroelasticity.
Design: Including Sec. 23.500, Structural design;
Sec. 23.505, Protection of structure; Sec. 23.510, Materials and
processes; and Sec. 23.515, Special factors of safety.
Structural occupant protection: Included in Sec.
23.600, Emergency conditions.
The FAA proposes removing the content of current appendix A to part
23, Simplified design load criteria; appendix C to part 23, Basic
landing conditions; appendix D to part 23, Wheel spin-up and spring-
back loads; and appendix I to part 23, Seaplane loads. The content of
these current part 23 appendices is more appropriate for inclusion in
means of compliance. The FAA also proposes removing appendix B to part
23, Reserved, since the content of this appendix was removed at
amendment 23-42 (56 FR 344, January 3, 1991). Refer to appendix 1 of
this preamble for a cross-reference table detailing how the current
regulations are addressed in the proposed part 23 regulations.
b. Specific Discussion of Changes
i. Proposed Sec. 23.300, Structural Design Envelope
Proposed Sec. 23.300 would require an applicant to determine the
structural design envelope, which describes the range and limits of
airplane design and operational parameters for which an applicant would
show compliance with the requirements of this subpart. Proposed Sec.
23.300 would capture the safety intent of current Sec. Sec. 23.321,
Loads--General, paragraphs (b) and (c); 23.333, Flight envelope,
paragraphs (a), (b), and (d); 23.335, Design airspeeds; 23.337, Limit
maneuvering load factors, paragraphs (a) and (b); and 23.343, Design
fuel loads, paragraphs (a) and (b).
Proposed Sec. 23.300 would require the applicant to determine and
document the range of airplane and operational parameters for which the
applicant will show compliance with the requirements of subpart C.
These parameters would include the design airspeeds and maneuver load
factors often depicted as a V-n diagram. An applicant would be required
to determine design airspeeds, including the design maneuvering speed
(VA), the design cruising speed (VC), the design
dive speed (VD), design flap and landing gear speeds, and
any other speed used as a design limitation. For certification of level
4 airplanes, an applicant would be required to determine a rough air
penetration speed, VB.
Additionally, applicants would have to determine the design
maneuver load factors based on the intended usage of the airplane and
the values associated with the level of safety experienced with current
designs. Applicants have rarely used the relief for maneuvering load
factors based on airplane capabilities in current Sec. 23.337(c). The
FAA views this relief as an application of physical principles, and
believes that this current requirement does not need to be addressed in
proposed Sec. 23.300.
Design weights and inertia parameters are also part of the
structural design envelope. Design weights include the empty weight,
maximum weight, takeoff and landing weight, and maximum zero fuel
weight. The range of center of gravity locations at these and other
weights is depicted as the weight center of gravity envelope. An
applicant would have to determine the weight and center of gravity of
occupants, payload, and fuel as well as any mass moments of inertia
required for loads or flutter analysis. An applicant would also have to
specify any other parameters that describe the structural design
envelope. These parameters include maximum
[[Page 13474]]
altitude limitations, Mach number limitations, and control surface
deflections.
ii. Proposed Sec. 23.305, Interaction of Systems and Structures
Proposed Sec. 23.305 would provide a regulatory framework for the
evaluation of systems intended to modify an airplane's structural
design envelope or structural performance and other systems whose
normal operating state or failed states may affect structural
performance. Compliance with proposed Sec. 23.305 would provide
acceptable mitigation of structural hazards identified in the
functional hazard assessments required by proposed Sec. 23.1315.
Proposed Sec. 23.305 would apply to airplanes equipped with--
Structural systems, including load alleviation systems,
where the intended function is to modify structural performance, to
alleviate the impact of subpart C requirements, or provide a means of
compliance to subpart C requirements; and
Systems where the intended function is non-structural, but
whose normal operation or failure states affect the structural design
envelope or structural performance, and would include fuel management
systems, flight-envelope protection systems, and active control
systems.
Under the current regulations, an applicant seeking certification
of airplanes incorporating structural and non-structural systems must
ensure that failures of these systems will not result in exceeding the
structural design envelope or the structural design loads, or other
structural performance characteristics. An applicant has the option of
designing the structure to the full subpart C and subpart D
requirements, including margins of safety, with the system in its
failed state. This option may result in increased structural weight and
reduced airplane performance and utility.
Proposed Sec. 23.1315 in subpart F would apply to both structural
and non-structural systems. Guidance material for current Sec.
23.1309, the corresponding regulation to proposed Sec. 23.1315, allows
for different acceptable values for likelihood of failures based on the
severity of the hazard, airplane weight, and method of propulsion.
These different values encourage the incorporation of equipment that
improves pilot situational awareness and other systems that promote the
overall airplane level of safety.
In most cases, means of compliance with proposed Sec. 23.305 would
follow an approach somewhat similar to that used in the guidance
material for current Sec. 23.1309. Structural failures resulting in
fatalities are rare, occurring at a rate of approximately 3 x
10-8 per flight hour for small airplanes. The reason for
incorporating structural systems is not, in general, to improve safety,
but rather to reduce structural weight and thereby improve airplane
performance. Proposed Sec. 23.305 would require that the level of
safety must be the same for airplanes equipped with systems that affect
the structure and airplanes without such systems.
An existing acceptable means of complying with proposed Sec.
23.305 is provided in several existing special conditions that address
the interaction of systems and structures, for example, FAA Special
Condition 25-390-SC.\20\ Most of these special conditions address load
alleviation systems. Load alleviation systems counteract the effects of
gust and maneuver loads and allow an applicant to design a lighter
structure, thereby improving the performance and utility of the
airplane. These special conditions require that an applicant design the
structure to the required structural safety margins with the load
alleviation system its normal functioning state. The special conditions
provide a means for an applicant to maintain the required structural
safety margins with the system in its failed state by adjusting the
required safety margins based on the likelihood of system failure.
Systems that fail frequently require higher safety margins than systems
that rarely fail in order to maintain the same level of safety. The
means of compliance described in these special conditions allow an
applicant to utilize the benefits of structural systems and potentially
eliminate weight and performance penalties associated with structural
hazards due to system failures.
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Applicants who use the means of compliance described in the
existing special conditions would be able to use data developed for
compliance with proposed Sec. 23.1315. This data includes
identification of failure modes, identification of hazards resulting
from the failure modes, and the likelihood of the occurrence of the
failure modes. With or without the proposed Sec. 23.305 requirements,
an applicant would have to account for structural performance with the
system in its normal operating and failed states and evaluate the
system for compliance to the proposed Sec. 23.1315. The FAA does not
expect that additional detailed structural analysis would be required
for compliance with proposed Sec. 23.305 other then the application of
optional lower safety margins to the structural performance analysis.
Proposed Sec. 23.305 would allow an applicant to realize the value
of structural and non-structural systems and would potentially allow
reduced structural weight of the airplane. The magnitude of the weight
reduction would depend on the functional characteristics of the systems
and the likelihood of system failures. The FAA believes proposed Sec.
23.305 would reduce the need for special conditions that deal with
interaction of systems and structures, saving time and effort for the
FAA and the applicant.
iii. Proposed Sec. 23.310, Structural Design Loads
Proposed Sec. 23.310 would require an applicant to determine
structural design loads resulting from any externally or internally
applied pressure, force, or moment, which may occur in flight, ground
and water operations, ground and water handling, and while the airplane
is parked or moored. Proposed Sec. 23.310 would require the applicant
to determine structural design loads at all combinations of parameters
on and within the boundaries of the structural design envelope which
result in the most severe loading conditions. Proposed Sec. 23.310
would also require the magnitude and distribution of these loads to be
based on physical principles and would be no less than service history
has shown can occur within the structural design envelope.
Proposed Sec. 23.310 would capture the safety intent of Sec. Sec.
23.301, Loads; 23.302, Canard or tandem wing configurations; 23.321,
Flight Loads--General, paragraph (a); and 23.331, Symmetrical flight
conditions. Proposed Sec. 23.310 would also capture the intent of
several current requirements for sound and physics-based engineering
evaluations. An example is in current Sec. 23.301(b), which requires
that the forces and moments applied to the airplane must balance in
equilibrium, and the distribution of loads on the airplane must
reasonably approximate actual conditions. The part 23 regulations
should not need to prescribe basic physical principles, sound
engineering judgment, and common sense. Proposed Sec. 23.310 would
place the burden on the applicant to properly account for loads acting
on the structure.
[[Page 13475]]
iv. Proposed Sec. 23.315, Flight Load Conditions
Proposed Sec. 23.315 would require an applicant to determine the
loads resulting from vertical and horizontal atmospheric gusts,
symmetric and asymmetric maneuvers, and, for multiengine airplanes,
failure of the powerplant unit which results in the most severe
structural loads. Proposed Sec. 23.315 would capture the safety intent
of current Sec. Sec. 23.333, Flight envelope, paragraph (c); 23.341,
Gust loads factors; 23.347, Unsymmetrical flight conditions; 23.349,
Rolling conditions; 23.351, Yawing conditions; 23.367, Unsymmetrical
loads due to engine failure; 23.421, Balancing loads; 23.423,
Maneuvering loads; 23.425, Gust loads; 23.427, Unsymmetrical loads;
23.441, Maneuvering loads; 23.443, Gust loads; and 23.445, Outboard
fins or winglets, paragraphs (b), (c), and (d).
These current part 23 sections establish prescriptive requirements
for gust loads and symmetrical, rolling, and yawing maneuvering loads,
acting on the wing, horizontal tail, vertical tail, and other lifting
surfaces. Portions of the current sections, such as Sec. 23.331(c),
are restatements of basic physical principles. Proposed Sec. 23.315
would remove this language.
The FAA's intent is not to lessen the structural load requirements.
The current prescriptive flight load requirements have established a
level of safety where structural failure due to overloading is rare.
When structural failures do occur, the most common cause is airplane
upset or pilot disorientation in instrument meteorological conditions.
The FAA believes the prescriptive content of the current
regulations, including the modified Pratt formula for gust loads, the
descriptions of symmetrical maneuvers, checked and unchecked maneuvers,
rolling maneuvers, and yawing maneuvers are more appropriate for
inclusion in means of compliance. Applicants who wish to propose
alternate design loading conditions should note that extensive data
collection, testing, and evaluation may be necessary to substantiate
their proposal.
v. Proposed Sec. 23.320, Ground and Water Load Conditions
Proposed Sec. 23.320 would require an applicant to determine the
loads resulting from taxi, take-off, landing, and ground handling
conditions occurring in normal and adverse attitudes and
configurations. Proposed Sec. 23.320 would capture the safety intent
of current Sec. Sec. 23.471, Ground Loads--General; 23.473, Ground
load conditions and assumptions; 23.477, Landing gear arrangement;
23.479, Level landing conditions; 23.481, Tail down landing conditions;
23.483, One-wheel landing conditions; 23.485, Side load conditions;
23.493, Braked roll conditions; 23.497, Supplementary conditions for
tail wheels; 23.499, Supplementary conditions for nose wheels; 23.505,
Supplementary conditions for skiplanes; 23.507, Jacking loads; 23.509,
Towing loads; 23.511, Ground load; unsymmetrical loads on multiple-
wheel units; 23.521, Water load conditions; 23.523, Design weights and
center of gravity positions; 23.525, Application of loads; 23.527, Hull
and main float load factors; 23.529 Hull and main float landing
conditions; 23.531, Hull and main float takeoff condition; 23.533, Hull
and main float bottom pressures; 23.535, Auxiliary float loads; 23.537,
Seawing loads, and 23.753 Main float design.
The current requirements set forth prescriptive requirements for
determining takeoff and landing loads for airplanes operated on land,
loads acting on floats and hulls for airplanes operated on water, as
well as ground handling loads, including jacking and towing conditions.
The current requirements also provide applicants with descriptions of
the normal and adverse operating conditions and configurations for
which applicants must determine ground and water loads.
The FAA believes that the prescriptive descriptions of the loading
conditions, normal and adverse conditions, and configurations are more
appropriate for inclusion in means of compliance. Applicants who wish
to propose alternate design loading conditions should note that
extensive data collection, testing, and evaluation may be necessary to
substantiate their proposal.
vi. Proposed Sec. 23.325, Component Loading Conditions
Proposed Sec. 23.325 would require an applicant to determine the
loads acting on each engine mount, flight control and high lift
surface, and the loads acting on pressurized cabins. Proposed Sec.
23.325 would capture the safety intent of current Sec. Sec. 23.345,
High lift devices; 23.361, Engine torque; 23.363, Side load on engine
mount; 23.365, Pressurized cabin loads; 23.371, Gyroscopic and
aerodynamic loads; 23.373, Speed control devices; 23.391, Control
surface loads; 23.393, Loads parallel to hinge line; 23.395, Control
system loads; 23.397, Limit control forces and torques; 23.399, Dual
control system; 23.405, Secondary control system; 23.407, Trim tab
effects; 23.409, Tabs; 23.415, Ground gust conditions; 23.455,
Ailerons; and 23.459, Special devices.
The current part 23 regulations establish prescriptive requirements
for determining loads acting on pressurized cabins, engine mounts and
attachment structure, control surfaces, high lift surfaces, and speed
control devices. The FAA believes that these prescriptive requirements
in the current regulations are more appropriate for inclusion in means
of compliance. However, in proposed Sec. 23.325, we have retained some
of the prescriptive requirements for pressurized cabins, including
descriptions of combined loading conditions and additional factors of
safety for determining limit load.
vii. Proposed Sec. 23.330, Limit and Ultimate Loads
Proposed Sec. 23.330 would describe how the applicant must
determine the limit and ultimate loads associated with the structural
design loads. Proposed Sec. 23.330 would capture the safety intent of
current Sec. Sec. 23.301, Loads, paragraph (a); and 23.303, Factor of
safety. These current sections specify factors of safety for
determining limit and ultimate loads.
Proposed Sec. 23.330 retains the current 1.5 safety factor for
ultimate loads. This safety factor has resulted in a service history
where structural failures due to applied static loads are rare. The FAA
believes the 1.5 factor of safety is critical to maintaining the
current level of safety.
Proposed Sec. 23.330 would allow for additional special factors of
safety to account for material and manufacturing variability. Proposed
Sec. 23.330 would also allow alternate factors of safety when showing
compliance with occupant protection loading conditions and when showing
compliance with proposed Sec. 23.305.
viii. Proposed Sec. 23.400, Structural Strength
Proposed Sec. 23.400 would require an applicant to demonstrate
that the structure will support limit and ultimate loads. Proposed
Sec. 23.400 would capture the safety intent of current Sec. Sec.
23.305, Strength and deformation; and 23.307, Proof of structure.
These current sections provide performance criteria for the
structure when subjected to limit and ultimate loads. Proposed Sec.
23.400 would retain these performance criteria and would require the
applicant to demonstrate that the structure will meet these performance
criteria. In this context, ``demonstrate'' means the applicant must
conduct structural tests to show
[[Page 13476]]
compliance with the structural performance requirements, unless the
applicant shows that a structural analysis is reliable and applicable
to the structure. The FAA proposes not to retain the ``3 second'' rule
in proposed Sec. 23.400. This prescriptive requirement in current
Sec. 23.305(b) requires the applicant to demonstrate that the
structure will support ultimate load for at least three seconds. The
FAA believes this prescriptive requirement is a statement of physical
principles and testing experience and is more appropriate for inclusion
in means of compliance.
ix. Proposed Sec. 23.405, Structural Durability
Proposed Sec. 23.405 would require an applicant to develop and
implement procedures to prevent structural failures due to foreseeable
causes of strength degradation, and to prevent rapid decompression in
airplanes with a maximum operating altitude above 41,000 feet. Proposed
Sec. 23.405 would also require an airplane to be reasonably capable of
continued safe flight and landing with foreseeable structural damage
caused by high-energy fragments from an uncontained engine or rotating
machinery failure. Proposed Sec. 23.405 would capture the safety
intent of current Sec. Sec. 23.365(e), Pressurized cabin loads;
23.571, Metallic pressurized cabin structures; 23.572, Metallic wing,
empennage, and associated structures; 23.573, Damage tolerance and
fatigue evaluation of structure; 23.574, Metallic damage tolerance and
fatigue evaluation of commuter category airplanes; 23.575, Inspections
and other procedures; and 23.627, Fatigue strength.
Proposed Sec. 23.405(a) would require an applicant to develop and
implement procedures to prevent structural failures. These procedures
may include the safe-life, damage tolerance, or fail-safe design
approaches described in the current regulations. An applicant can
propose other means of compliance, but these means must provide at
least the same level of safety as current means of compliance. Any new
means of compliance must consider the airplane design, manufacturing,
operational, and maintenance environments. The FAA proposes
implementing these procedures by including them in the airplane's
Instructions for Continued Airworthiness.
The procedures must be able to prevent structural failures due to
foreseeable causes of strength degradation. Foreseeable causes include
fatigue and corrosion in metallic structures, and fatigue,
delaminations, disbonds, and impact damage in composite structures. New
material systems or structural designs, such as additive manufacturing,
may introduce new causes of strength degradation and may require
development of new and unique procedures to prevent structural
failures.
The current part 23 regulations use prevention of catastrophic
failures as the safety intent of the regulations. The word
``catastrophic'' is used throughout the current regulations, current
policy, and guidance material, especially in context of system safety
analysis. To avoid any potential conflict over the meaning of
``catastrophic,'' proposed Sec. 23.405(a) would specify the
consequences we want to prevent. These consequences include the obvious
performance criteria for prevention of serious injuries, fatalities, or
hull loss of the airplane.
The FAA also wants to prevent extended periods of operations with
reduced safety margins in those structural components whose failure
could result in serious injuries, fatalities, or hull loss. One
situation that can result in reduced safety margins is fail-safe
design. The FAA has identified potential shortcomings in fail-safe
designs, including an applicant's difficulty to anticipate all possible
failure scenarios and ensure that all structural failures would be
immediately obvious and corrected before further flight. The concept of
failures being obvious and repaired before further flight is basic to
the successful implementation of a fail-safe design. This scenario
could allow operation for extended periods with a passive structural
failure and reduced safety margins. If an applicant chooses fail-safe
design as a means of compliance, an applicant would have to ensure that
the structure was not operating for extended periods with reduced
safety margins. An applicant may be able to apply safe-life or damage
tolerance principles to ensure that fail-safe structure maintains the
required safety margins without extended periods of operation with
reduced safety margins through life limits or damage tolerance based
inspections.
Proposed Sec. 23.405(b) would capture the safety intent of current
Sec. 23.365(e), requiring the applicant to design the structure for
sudden loss of pressurization after the failure of a door or window in
pressurized compartments. Proposed Sec. 23.405(c) incorporates the
safety intent of current Sec. 23.571(d). Our intention is that the
damage tolerance methodology would remain the accepted means of
compliance. The FAA views damage tolerance as necessary since current
Sec. 23.571(d) and proposed Sec. 23.405(c) require the applicant to
assume that structural damage exists in the pressurized cabin. However,
proposed Sec. 23.405(c) would allow for other means of compliance as
long as serious injuries and fatalities will be prevented. Examples of
other means of compliance might include requiring pilots and occupants
to use oxygen masks or wear pressurized flight suits when operating
above 41,000 feet (12,497 meters). This means of compliance could be
acceptable in certain airplane designs, such as two-seat jet trainers.
Proposed Sec. 23.405(d) would capture the safety intent of current
Sec. 23.903(b)(1) to minimize hazards to the airframe resulting from
turbine engine rotorburst. The FAA would move the structural portion of
the rotorburst evaluation from current Sec. 23.903(b)(1) to proposed
Sec. 23.405(d) to ensure all structural requirements are contained in
subpart C and to avoid potential confusion over the structural
rotorburst requirements in part 23.
Proposed Sec. 23.405(d) would require an applicant to show that
the design of the structure would provide sufficient structural
capability to allow continued safe flight and landing with foreseeable
structural damage caused by high energy fragments from an uncontained
engine or rotating machinery failure. The FAA recognizes that some
high-energy fragment events may result in catastrophic failures that
may not be avoidable and that complete elimination of the hazards
resulting from high energy fragment events may not be possible.
An applicant would be required to address other sources of high
energy rotating machinery fragments in the proposed structural
rotorburst requirements. Our intent is to ensure an adequate regulatory
framework for applications of electrical propulsion systems and other
unique and novel approaches to propulsion, which may release high-
energy fragments.
Applicants who have shown compliance with current Sec.
23.903(b)(1) would be able to show compliance with proposed Sec.
23.405(d). Applicants should note that previous certification programs
with turbine engine installations have been able to show that the
airplane structure is capable of continued safe flight and landing
following a rotorburst event. AC 23-13A, Fatigue, Fail-Safe, and Damage
Tolerance Evaluation of Metallic Structure for Normal, Utility,
Acrobatic, and Commuter Category airplanes, provides guidance on the
required structural evaluation.
[[Page 13477]]
x. Proposed Sec. 23.410, Aeroelasticity
Proposed Sec. 23.410 would require an airplane to be free from
flutter, control reversal, and divergence at all speeds within and
sufficiently beyond the structural design envelope, for any
configuration and condition of operation, accounting for critical
degrees of freedom, and any critical failures or malfunctions. Proposed
Sec. 23.410 would also require an applicant to establish tolerances
for all quantities that affect flutter.
Proposed Sec. 23.410 would capture the safety intent of the
current Sec. Sec. 23.629, Flutter; 23.677, Trim systems, paragraph
(c); and 23.687, Spring devices, in part. Specifically, proposed Sec.
23.410 would address the safety intent of these rules by requiring
freedom from flutter, control reversal, and divergence, while
accounting for all speeds, configurations, modes, and failures, and to
establish tolerances on anything affecting flutter. The current Sec.
23.629(a) states that freedom from flutter, control reversal, and
divergence must be shown by the methods of Sec. 23.629(b) and (c) or
(d). These paragraphs are prescriptive in nature and some portions are
applicable only to very specific types of designs and include speed
limitations. Therefore, these paragraphs are more appropriate as means
of compliance.
The current Sec. 23.629(e) requires the evaluation of whirl mode
flutter. Since this is another flutter mode, it must be accounted for
when an airplane is determined to be free from flutter. The current
Sec. 23.629(f), (g), (h), and (i) provide instructions on how to
evaluate (1) certain airplane design types, (2) designs employing
certain methods (fail-safe or damage tolerant), or (3) airplanes
incorporating design modifications. The current Sec. 23.677(c)
requires either that the tab be balanced or that the tab controls be
irreversible. Additionally, it requires that irreversible tab systems
have adequate rigidity and reliability. These are very specific design
solutions for ensuring freedom from flutter. The current Sec. 23.687
requires that the reliability of spring devices used in control systems
be established by tests unless its failure would not cause flutter.
This is a method of compliance to ensure freedom from flutter. All of
these current requirements are more appropriate as means of compliance
because they describe how to ensure freedom from flutter, control
reversal, and divergence. They are not the safety intent, but just one
method to achieve the safety intent. As such, they serve only specific
designs utilizing current methods, and may or may not be adequate for
innovative designs or accommodate new analytical methods or testing
techniques.
xi. Proposed Sec. 23.500, Structural Design
Proposed Sec. 23.500 would require an applicant to design each
part, article, and assembly for the expected operating conditions of
the airplane. Proposed Sec. 23.500 would require the design data to
adequately define the part, article, or assembly configuration, its
design features, and any materials and processes used. Proposed Sec.
23.500 would require an applicant to determine the suitability of each
design detail and part having an important bearing on safety in
operations. Proposed Sec. 23.500 would also require the control system
to be free from--
Jamming;
Excessive friction, and
Excessive deflection when the control system and its
supporting structure are subjected to loads corresponding to the limit
airloads when the primary controls are subjected to the lesser of the
limit airloads or limit pilot forces and when the secondary controls
are subjected to loads not less than those corresponding to maximum
pilot effort.
Proposed Sec. 23.500 would capture the safety intent of the
current Sec. Sec. 23.601, Design and Construction--General; 23.603,
Materials and workmanship, paragraph (b); 23.671, Control Systems--
General, paragraph (a); 23.683, Operation tests; 23.685, Control system
details; 23.687, Spring devices, in part; and 23.689, Cable systems.
These current requirements explain methods and techniques to ensure an
adequate design. The proposed rule would require an applicant to
produce an adequate design without specifying how. The prescriptive
language within these current sections noted above, are more
appropriate for a means of compliance.
xii. Proposed Sec. 23.505, Protection of Structure
Proposed Sec. 23.505 would require an applicant to protect each
part of the airplane, including small parts such as fasteners, against
deterioration or loss of strength due to any cause likely to occur in
the expected operational environment. Proposed Sec. 23.505 would
require each part of the airplane to have adequate provisions for
ventilation and drainage and would require an applicant to incorporate
a means into the airplane design to allow for required maintenance,
preventive maintenance, and servicing.
Proposed Sec. 23.505 would capture the safety intent of the
current Sec. Sec. 23.607, Fasteners; 23.609, Protection of structure;
and 23.611, Accessibility. These current requirements explain methods
and techniques to ensure an adequate design. This proposed rule would
require the applicant to produce an adequate design without specifying
how to accomplish it. The prescriptive language within these current
sections is more appropriate as a means of compliance.
xiii. Proposed Sec. 23.510, Materials and Processes
Proposed Sec. 23.510 would require an applicant to determine the
suitability and durability of materials used for parts, articles, and
assemblies, the failure of which could prevent continued safe flight
and landing, while accounting for the effects of likely environmental
conditions expected in service. Proposed Sec. 23.510 would require the
methods and processes of fabrication and assembly used to produce
consistently sound structures and, if a fabrication process requires
close control to reach this objective, an applicant would have to
perform the process under an approved process specification.
Additionally, proposed Sec. 23.510 would require an applicant to
justify the selected design values to ensure material strength with
probabilities, account for--
The criticality of the structural element; and
The structural failure due to material variability, unless
each individual item is tested before use to determine that the actual
strength properties of that particular item would equal or exceed those
used in the design, or the design values are accepted by the
Administrator.
Proposed Sec. 23.510 would require a determination of required
material strength properties to be based on sufficient tests of
material meeting specifications to establish design values on a
statistical basis. Proposed Sec. 23.510 would also require an
applicant to determine the effects on allowable stresses used for
design if thermal effects were significant on an essential component or
structure under normal operating conditions.
Proposed Sec. 23.510 would capture the safety intent of the
current Sec. Sec. 23.605, Fabrication methods and 23.613, Material
strength properties and design values. These current requirements
explain methods and techniques to ensure adequate materials and process
controls. This proposed rule would require the applicant to ensure the
resulting materials and processes are adequate without specifying how.
The prescriptive language within the current
[[Page 13478]]
sections is more appropriate as a means of compliance.
xiv. Proposed Sec. 23.515, Special Factors of Safety
Proposed Sec. 23.515 would require an applicant to determine a
special factor of safety for any critical design value that was
uncertain, used for a part, article, or assembly likely to deteriorate
in service before normal replacement, or subject to appreciable
variability because of uncertainties in manufacturing processes or
inspection methods. Proposed Sec. 23.515 would require an applicant to
determine a special factor of safety using quality controls and
specifications that accounted for each structural application,
inspection method, structural test requirement, sampling percentage,
and process and material control. Proposed Sec. 23.515 would require
an applicant to apply any special factor of safety in the design for
each part of the structure by multiplying each limit load and ultimate
load by the special factor of safety.
Proposed Sec. 23.515 would capture the safety intent of current
Sec. Sec. 23.619, Special factors; 23.621, Casting factors; 23.623,
Bearing factors; 23.625, Fitting factors; 23.657, Hinges; 23.681(b),
Limit load static test (in part); and 23.693, Joints. These current
requirements explain methods and techniques to ensure adequate special
factors are used and the proposed rule would simply require the
applicant to determine and apply adequate special factors without
specifying what these are. The prescriptive language within the current
sections is more appropriate as a means of compliance.
xv. Proposed Sec. 23.600, Emergency Conditions
Proposed Sec. 23.600 would require the airplane, even if damaged
in emergency landing conditions, to provide protection to each occupant
against injury that would preclude egress. Proposed Sec. 23.600 would
require the airplane to have seating and restraints for all occupants,
consisting of a seat, a method to restrain the occupant's pelvis and
torso, and a single action restraint release, which meets its intended
function and does not create a hazard that could cause a secondary
injury to an occupant. Proposed Sec. 23.600 would require the airplane
seating, restraints, and cabin interior to account for likely flight
and emergency landing conditions. Additionally, they could not prevent
occupant egress or interfere with the operation of the airplane when
not in use.
Proposed Sec. 23.600 would require each baggage and cargo
compartment be designed for its maximum weight of contents and for the
critical load distributions at the maximum load factors corresponding
to the determined flight and ground load conditions. Proposed Sec.
23.600 would also require each baggage and cargo compartment to have a
means to prevent the contents of the compartment from becoming a hazard
by impacting occupants or shifting, and to protect any controls,
wiring, lines, equipment, or accessories whose damage or failure would
affect operations.
Proposed Sec. 23.600 would capture the safety intent of current
Sec. Sec. 23.561, Emergency Landing Conditions--General; 23.562,
Emergency landing dynamic conditions; 23.785, Seats, berths, litters,
safety belts, and shoulder harnesses; and 23.787, Baggage and cargo
compartments. The prescriptive language within these current sections
are more appropriate as a means of compliance, and thus would allow
flexibility for new technology to be available in new part 23 airplanes
in a timely manner.
Occupant safety for aviation has progressed incrementally over the
years. This has resulted in rulemaking that has enhanced safety for
individual system components, but not in an integrated fashion.
Modeling and analysis techniques have matured to a point that may allow
evaluation of more crash scenarios and crashworthiness components as an
integrated system. The FAA has relied on many industry studies to
develop current occupant safety rules. These studies evaluated
characteristics of actual accidents, full-scale aircraft drop testing,
and dynamic seat testing on a sled. When dynamic seat testing began,
determination of an adequate generic floor impulse that represented a
survivable aircraft crash was established. As an alternative to current
crashworthiness requirements, the proposed rule would allow for
evaluation of the conditions of likely impacts, assessment of vehicle
response, and ultimately, evaluation of occupant reaction to vehicle
impact and vehicle response.
Technology used in aviation crashworthiness, in a large part, has
come from the automotive industry. The automotive industry has analyzed
crashworthiness components as a system for many years. The automotive
industry generally has a more developed crashworthiness analysis
capability than that used in the aviation industry. This advanced
crashworthiness analysis capability has evolved primarily because of
the--
Public expectation for automobile safety;
Higher general public likelihood and exposure to
automobile accidents; and
High automobile production rates allow for multiple actual
full-vehicle crash tests that result in very accurate crash impulse
data from the outer surface of the vehicle all the way to the occupant.
Because of these facts, automotive designers know accurate impulses
and the specific vehicle response for impact conditions. Furthermore,
this data can be extrapolated to consider many more accident scenarios.
Automotive safety requirements progressively add new impact scenario
requirements and enhanced impulse magnitudes, thus requiring more
industry innovation. This innovation has enabled rapid advances in
automotive occupant protection systems.
Automotive safety begins at the outside of the vehicle, evaluating
the entire system's response. In contrast, aircraft manufacturers have
used essentially the same generic designed pulse imparted at the cabin
floor for the last 25 years. The same impulse applies to all GA
airplanes independent of the structure below the cabin floor and the
aircraft's stall speed, unless the stall speed is greater than 61
knots. Determining airplane crashworthiness is a more complex process
than determining automotive crashworthiness because of higher impact
speeds, lighter weight structures, and the effect of the third
dimension of altitude on the aircraft. Dynamic seat testing has
improved crashworthiness in aviation; however, the FAA believes that
newer means of evaluating the full aircraft response to crash
conditions via modeling, newer materials, and new technologies promise
to offer improved features, evaluation, and accuracy that would
facilitate consideration of more crash scenarios and evaluation of more
variables that could improve survivability.
The NTSB produced a series of reports, called the General Aviation
Crashworthiness Project,\21\ in the 1980s that evaluated over 21,000 GA
airplane crashes that occurred between 1972 and 1981. The NTSB
evaluated airplane orientation, impact magnitudes, and survival rates
and factors on many of these accidents in order to provide information
to support changes in crashworthiness design standards for seating and
restraint systems in GA airplanes. These reports also established
[[Page 13479]]
conditions approximating survivable accidents, and categorized factors
that would have the largest impact on safety. These reports further
illuminated the various crashworthiness systems and their respective
impact to overall safety. Amendment 23-36 (53 FR 30802, August 15,
1988), to part 23 referenced these reports for dynamic seats but did
not adopt a systems-approach to evaluating crashworthiness of an
airplane design.
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\21\ See www.regulations.gov (Docket #FAA-2015-1621).
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The NTSB reports identified several factors that would enhance
safety. All of these factors working together as a system should result
in a safer airplane. However, the assessment indicated that shoulder
harnesses offer the fastest individual improvement for safety. The FAA
codified the shoulder harnesses requirement in amendments 23-19 (42 FR
20601, June 16, 1977) and 23-32 (50 FR 46872, November 13, 1985), for
newly manufactured airplanes. The FAA also issued policy statement ACE-
00-23.561-01,\22\ Methods of Approval of Retrofit Shoulder Harness
Installations in Small Airplanes, to streamline the process for
retrofitting older airplanes.
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\22\ See www.regulations.gov (Docket #FAA-2015-1621).
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Survivable volume is another critical factor to survival.
Survivable volume is the ability of the airframe to protect the
occupants from external intrusion or cabin crushing during and after
the accident sequence. There were several observed accidents in the
NTSB study where conventional aircraft construction simply crushed an
otherwise restrained occupant. Crashworthiness regulations have never
included survivable volume as a factor, except for aircraft turnover.
Airplane designs should provide the space needed for the protection and
restraint of the occupants. A compromised survivable volume could cause
occupant impact with objects in the cabin. This is one of the first
steps in the analysis of airplane crashworthiness.
Additional data from the NTSB General Aviation Crashworthiness
Project suggested that energy-absorbing seats that protect the occupant
from vertical loads could enhance occupant survivability and work to
prevent serious injury, thereby enhancing odds for egress and
preventing many debilitating long-term injuries. The FAA established
dynamic seat testing requirements in amendment 23-36 for airplanes
certificated under part 23. Energy absorbing seats benefit a smaller
portion of accident occupants because accident impacts with larger
vertical components tend to reduce occupant survival odds. Energy
attenuation from vertical forces, both static and dynamic, has been
important to crashworthiness regulations within the past 25 years. Seat
deformation throughout the emergency landing sequence is acceptable if
the load path through attachment, seat, and restraint remains
continuous. Coupling the seat performance to the rest of the airframe
response is important to the enhancement and understanding of occupant
survivability. The FAA believes that allowing designers to consider a
particular airframe's unique deformation in a crash, the designers can
create a safer cabin for the occupants. Using unique airframe
deformations would result in more accurate accident floor impulses and
may allow evaluation of crash impulses in multiple directions; instead
of only two directions considered in current certification.
Occupant restraints must maintain integrity, stay in place on the
occupant throughout the event, properly distribute loads on the
occupant, and restrain the occupant by mitigating interaction with
other items in the cabin. Restraints originally were comprised of lap
belts. Shoulder harnesses were later required as discussed above. Newer
technology that enhances or supplements the performance of restraints,
like airbags and consideration of items in the cabin that the occupant
might impact, are now being considered for inclusion in designs. The
use of airbags has greatly increased passenger safety in automobiles,
which offer protection in much more severe impacts and in impacts from
multiple directions, and could be a viable option for airplanes as
well.
Seat retention in airplanes is a factor identified as another basic
building block for crashworthiness. The NTSB reports shows more than a
quarter of otherwise-survivable accidents included instances where the
seats broke free at the attachment to the airplane, resulting in
fatalities or serious injuries. Dynamic seat testing requirements
address the ability of seat assemblies to remain attached to the floor,
even when the floor shifts during impact. Pitching and yawing of the
seat tracks during dynamic seat tests demonstrates the gimbaling and
flexibility of the seat.
All of the aforementioned safety considerations must work together
to enhance occupant safety and survivability. The FAA believes that
evaluating occupant safety, as a whole system, would allow for a better
understanding of vehicle performance in an emergency landing, enabling
the incorporation of innovative technology. The transportation industry
has made significant progress with energy absorbing seats and restraint
technology. The FAA believes enhanced cabin strength that improves
survivable volume, coupled with better restraint technology and refined
energy absorbing seats, would be key factors in improving expansion of
the survivable accident envelope. These factors and additional
considerations were included in the Small Airplane Crashworthiness
Design Guide.\23\ This guide was prepared for the Advanced General
Aviation Transports Experiments and the National Aerospace and Space
Administration and addresses the concept of designing crashworthiness
into an airplane design as a system.
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\23\ See www.regulations.gov (Docket #FAA-2015-1621).
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In order to evaluate an accident from an occupant's perspective,
the emergency landing condition must first be defined, starting with
the conditions external to the aircraft. In most survivable accidents,
the pilot is able to maintain control of the aircraft prior to impact.
Accidents where the airplane impacts the ground out of control are
typically much less survivable. Speed and impact orientation are
significant factors in crash survivability. Therefore, considerations
for impact beyond a controllable impact are beyond the scope of these
proposed regulations. The slowest forward speed that any fixed wing
airplane can fly is its stall speed. This stall speed can vary with
airplane configuration and weight, but represents the most universal
parameter for impact speed and energy attenuation at impact. For this
reason, stall speed is the starting point for consideration of expected
impact conditions.
Orientation of impact can vary with pitch, yaw, terrain angle, and
angle of flight path and becomes dynamic as the pilot loses control
effectiveness at stall. The result is the airplane impact angle can
result in a combination of horizontal and vertical loads and impulses
that vary widely. Angle of impact, the line of the center of mass with
respect to the angle of the impact surface, can also affect the amount
of energy absorbed or transmitted to the occupant.
An accident impulse is a dynamic event that rapidly loads and
unloads the structure. Dynamic impacts accurately represent the impact
event, often including load levels far surpassing the static load
requirements. Dynamic testing is also subject to a wide variation of
results due to the unpredictable dynamic responses of varying
[[Page 13480]]
construction methods and materials, resulting in complicated modeling
and analysis. This contrasts with static load tests that load the
structure slowly, maintain that load at high levels, are generally
simpler, and often provide adequate demonstration of part strength.
Static analysis is generally more reliable with both testing and
modeling; however, it does not capture the nature of rapid loading.
Some combination of dynamic and static testing allows for the best
understanding of airplane behavior during an accident.
Compliance with the proposed rule could be shown using conventional
means of compliance like dynamic testing of seats, and static testing
of other components using the prescriptive methods contained in the
current part 23. Alternative compliance methods could include analysis
or modeling supported by testing using an airframe coupled with the
airplane's performance envelope, viewing the entire interaction of
ground, airplane, and occupant, thus using a more complete systemic
approach to achieve improved protection.
Proposed Sec. 23.600(a) is intended to provide structural
performance that protects the occupant during an emergency landing
while accounting for only static loads and assuming all safety
equipment is in use. The proposed section would capture the safety
intent of the current Sec. 23.561. As noted earlier, static loads are
generally lower than peak dynamic loads; however, they may offer a
more-easily predictable loading condition and are generally of longer
duration such that the structure can fully react to the load. The
landing conditions should consider possible accident sequence variables
at impact, including restraint of items of mass within the cabin,
directions of loading along or about the three axes, and airframe
response with respect to the occupants and effects of airframe
deflection during an emergency landing. Effects of emergency landing on
the airplane should also be considered to include the effect of
airframe damage and how static loads would affect egress and survivable
cabin volume. Items of mass within the cabin and rear mounted engines
have also been traditionally considered using even higher static loads
as an additional factor of safety to ensure that these items of mass
are restrained and would be among the last items to come free in an
accident.
Proposed Sec. 23.600(b) is intended to provide boundary conditions
for the emergency landing sequence for both static and dynamic load
considerations. The proposed section would capture the safety intent of
the current Sec. Sec. 23.561 and 23.562. The airplane stall speed
limits the maximum forward impact speed. The emergency landing
condition assumes the pilot maintains airplane control at or near final
impact, thereby limiting impact velocity.
Proposed Sec. 23.600(c) would capture the survivability factors
for the occupant in the cabin during the emergency landing sequence and
would capture the safety intent of current Sec. 23.562. These factors
include proper use and loading of seats and restraints, and the
interaction of the occupants with each other and the cabin interior.
Survivability is determined upon the occupant's interaction with the
interior, seat, and restraints, and bounded by established human injury
criteria.
Proposed Sec. 23.600(d) would provide the framework for seats and
occupant restraints and would require simplified seat and restraint
requirements for all occupants. This proposed section would capture the
safety intent of current Sec. 23.785.
Proposed Sec. 23.600(e) would establish requirements for baggage
and cargo compartments and the restraint of contents. The proposed
section would capture the safety intent of current Sec. 23.787.
xvi. Current Subpart C Regulations Relocated to Other Proposed Subparts
As discussed, the FAA proposes removing current Sec. Sec. 23.561,
23.562, 23.785, and 23.787. Also, this proposal would consolidate the
safety intent of these crashworthiness regulations in proposed Sec.
23.600.
4. Subpart D--Design and Construction
a. General Discussion
The FAA proposes restructuring current subpart D to retain the
requirements for flight control systems, along with their attachment to
the structure and landing gear, and occupant safety other than
structural requirements. The FAA proposes to align structural
requirements, found in current Sec. Sec. 23.601 through 23.659, to
proposed subpart C. Aspects that directly affected the pilot's
interface with the airplane, such as the throttle shape, would be
relocated to proposed Sec. 23.1500, Flightcrew Interface.
The FAA also proposes, in those sections where there are
requirements specific to the current commuter category, to use
certification level 4. In those sections where there are current
requirements specific to multiengine jets over 6,000 pounds, the FAA
proposes requirements for certification level 3, high-speed multiengine
airplanes as discussed earlier in this proposal. Refer to appendix 1 of
this preamble for a cross-reference table detailing how the current
regulations are addressed in the proposed part 23 regulations.
The subpart D organization was more complex than other subparts due
to the relocation and removal of many requirements at the sub-paragraph
level. To reduce confusion, the specific discussion of subpart D
changes is shown in a cross reference table at the end of the specific
discussion section below rather than the Relocation and Removal
paragraphs in other subparts.
b. Specific Discussion of Changes
i. Proposed Sec. 23.700, Flight Controls Systems
Proposed Sec. 23.700 would require an applicant to design airplane
flight control systems to prevent major, hazardous, and catastrophic
hazards. Proposed Sec. 23.700 would require an applicant to design
trim systems to prevent inadvertent, incorrect, or abrupt trim
operation. In addition, proposed Sec. 23.700 would require an
applicant to design trim systems to provide a means to indicate--
The direction of trim control movement relative to
airplane motion;
The trim position with respect to the trim range;
The neutral position for lateral and directional trim; and
For all airplanes except simple airplanes, the range for
takeoff for all applicant requested center of gravity ranges and
configurations.
Proposed Sec. 23.700 would also require an applicant to design
trim systems to provide control for continued safe flight and landing
when any one connecting or transmitting element in the primary flight
control system failed, except for simple airplanes. Additionally,
proposed Sec. 23.700 would require an applicant to design trim systems
to limit the range of travel to allow safe flight and landing, if an
adjustable stabilizer is used.
Furthermore, proposed Sec. 23.700 would require the system for an
airplane equipped with an artificial stall barrier system to prevent
uncommanded control or thrust action and provide for a preflight check.
The FAA also proposes requiring an applicant seeking certification of a
certification level 3 high-speed or certification level 4 airplane to
install a takeoff warning system on the airplane, unless the applicant
demonstrates that the airplane, for each configuration, could takeoff
at the limits of its trim and flap ranges.
Proposed Sec. 23.700(b)(3) would also allow an exception for
simple airplanes
[[Page 13481]]
from the requirement to provide control for continued safe flight and
landing when any one connecting or transmitting element in the primary
control system fails. This would provide a level of safety equivalent
to that specified in EASA's CS-VLA. Last, proposed Sec. 23.700(d)
would maintain the level of safety in the current requirements for a
takeoff warning system.
Proposed Sec. 23.700 would capture the safety intent of current
Sec. Sec. 23.677, Trim systems, paragraphs (a), (b), and (d); 23.689,
Cable systems, paragraphs (a) and (f); 23.691, Artificial stall barrier
system, paragraphs (a), (b), (d), (e) and (f); 23.697, Wing flap
controls, paragraphs (a); and 23.703, Takeoff warning system,
paragraphs (a) and (b). This proposed section would apply to the
function, usability, and hazard levels of all mechanical, electrical,
or electronic control systems. The certification levels proposed in
this NPRM would be incorporated into the mechanical, electrical, or
electronic control systems to maintain the differences in airplanes
certificated under part 23 (i.e., weight and powerplant.)
ii. Proposed Sec. 23.705, Landing Gear Systems
Proposed Sec. 23.705 would require an airplane's landing gear and
retracting mechanism be able to withstand operational and flight loads.
Proposed Sec. 23.705 would require an airplane with retractable
landing gear to have a positive means to keep the landing gear extended
and a secondary means for extending the landing gear that could not be
extended using the primary means. Proposed Sec. 23.705 would also
require a means to inform the pilot that each landing gear is secured
in the extended and retracted positions. Additionally, proposed Sec.
23.705 would require an airplane, except for airplanes intended for
operation on water, with retractable landing gear to also have a
warning to the pilot if the thrust and configuration is selected for
landing and yet the landing gear is not fully extended and locked.
Furthermore, if the landing gear bayis used as the location for
equipment other than the landing gear, proposed Sec. 23.705 would
require that equipment be designed and installed to avoid damage from
tire burst and from items that may enter the landing gear bay. Proposed
Sec. 23.705 would also require the design of each landing gear wheel,
tire, and ski account for critical loads and would require a reliable
means of stopping the airplane with kinetic energy absorption within
the airplane's design specifications for landing. For certification
level 3 high-speed multiengine and certification level 4 multiengine
airplanes, proposed Sec. 23.705 would require the braking system to
provide kinetic energy absorption within the design of the airplane
specifications for rejected takeoff as the current rules do for
multiengine jets over 6,000 pounds and commuter category airplanes.
Proposed Sec. 23.705 would capture the safety intent of current
Sec. Sec. 23.729, Landing gear extension and retraction system,
paragraphs (a), (b), (c), and (e); 23.731, Wheels; 23.733, Tires,
paragraph (a); 23.735, Brakes, paragraphs (a), (b), and (e); 23.737,
Skis. The FAA proposes to combine the fixed and retractable landing
gear systems into the proposed section, which would apply to the
function, usability, and hazard levels of all mechanical, electrical,
or electronic landing gear systems.
iii. Proposed Sec. 23.710, Buoyancy for Seaplanes and Amphibians
Proposed Sec. 23.710 would require airplanes intended for
operations on water to provide buoyancy of 80 percent in excess of the
buoyancy required to support the maximum weight of the airplane in
fresh water. Proposed Sec. 23.710 would also require airplanes
intended for operations on water to have sufficient watertight
compartments so the airplane will stay afloat at rest in calm water
without capsizing if any two compartments of any main float or hull are
flooded.
Proposed Sec. 23.710 would capture the safety intent of current
Sec. Sec. 23.751(a), Main float buoyancy; 23.755, Hulls; and 23.757,
Auxiliary floats. The FAA proposes combining the floats or hulls
landing gear systems into the proposed section and having it apply to
the function, usability, and hazard levels of hulls and floats. The
existing rule requires at least four watertight compartments of
approximately equal volume, which the FAA proposes to remove because
they are specific design requirements and are addressed in the proposed
performance-based requirements.
To encourage the installation of buoyancy systems with new safety
enhancing technology and streamlining the certification process, the
FAA proposes removing most of the current prescriptive requirements and
the detailed means of compliance for these requirements from the
current part 23 and replacing them with performance-based regulations.
The FAA expects the current means of compliance would continue to be
used for the traditional airplane designs under part 23.
iv. Sec. 23.750, Means of Egress and Emergency Exits
Proposed Sec. 23.750 would require the airplane cabin exit be
designed to provide for evacuation of the airplane within 90 seconds in
conditions likely to occur, excluding ditching, following an emergency
landing. For ditching, proposed Sec. 23.750 would require the cabin
exit for all certification levels 3 and 4 multiengine airplanes be
designed to allow evacuation in 90 seconds. Proposed Sec. 23.750 would
require each exit to have a simple and obvious means, marked inside and
outside the airplane, to be opened from both inside and outside the
airplane, when the internal locking mechanism is in the locked
position.
Proposed Sec. 23.750 would also require airplane evacuation paths
to protect occupants from serious injury from the propulsion system,
and require that doors, canopies, and exits be protected from opening
inadvertently in flight. Proposed Sec. 23.750 would preclude each exit
from being obstructed by a seat or seat back, unless the seat or seat
back could be easily moved in one action to clear the exit. Proposed
Sec. 23.750 would also require airplanes certified for aerobatics to
have a means to exit the airplane in flight.
Proposed Sec. 23.750 would capture the safety intent of current
Sec. Sec. 23.783, Doors, paragraphs (a), (b), (c), and (d); 23.791,
23.803, Emergency evacuation, paragraph (a); 23.805, Flightcrew
emergency exits; 23.807, Emergency exits except paragraphs (a)(3),
(b)(1), (c), (d)(1) and (d)(4); 23.811, Emergency exit marking; 23.812,
Emergency lighting; 23.813, Emergency exit access, paragraph (a); and
23.815, Width of aisle; and CS-VLA-783, Exits. This proposed rule would
incorporate the requirements for all door and emergency exits and
remove specified design solutions and means of compliances.
To encourage the installation of egress and emergency exits with
new safety enhancing technology and streamline the certification
process, the FAA proposes removing most of the current prescriptive
requirements and the detailed means of compliance for these
requirements from the current part 23. The FAA expects that the current
prescriptive means of compliance would continue to be used for
traditional part 23 airplane designs.
The FAA would continue to accept an airplane designed to meet these
prescriptive design constraints as means of compliance to meet the
proposed performance standard. However, if an airplane did not meet the
prescriptive design constraints, the applicant could
[[Page 13482]]
propose its own means of compliance to show compliance with the
proposed performance standard. Historically, the FAA has accepted an
emergency evacuation demonstration in less than 90 seconds as an ELOS
for airplanes that did not meet the prescriptive design requirements in
the current part 23 regulations. AC 20-118A, Emergency Evacuation
Demonstration, contains an acceptable means of compliance for the 90-
second requirement for emergency evacuation.
v. Proposed Sec. 23.755, Occupant Physical Environment
Proposed Sec. 23.755 would require an applicant to design the
airplane to allow clear communication between the flightcrew and
passengers and provide a clear, sufficiently undistorted external view
to enable the flightcrew to perform any maneuvers within the operating
limitations of the airplane. Proposed Sec. 23.755 would also require
an applicant to design the airplane to protect the pilot from serious
injury due to high energy rotating failures in systems and equipment,
and protect the occupants from serious injury due to damage to
windshields, windows, and canopies.
Additionally, proposed Sec. 23.755 would require, for
certification level 4 airplanes, each windshield and its supporting
structure directly in front of the pilot to withstand the impact
equivalent of a two-pound bird at maximum approach flap airspeed and
allow for continued safe flight and landing after the loss of vision
through any one panel.
Furthermore, proposed Sec. 23.755 would require any installed
oxygen system to include a means to determine whether oxygen is being
delivered and a means for the flightcrew to turn on and shut off the
oxygen supply, and the ability for the flightcrew to determine the
quantity of oxygen available. Proposed Sec. 23.755 would also require
any installed pressurization system to include a pressurization system
test and a warning if an unsafe condition exists.
Proposed Sec. 23.755 would capture the safety intent of current
Sec. Sec. 23.771, Pilot compartment, paragraphs (b) and (c); 23.775,
Windshields and windows, paragraphs (a), (b), (c), (d), and (h);
23.831, Ventilation; 23.841, Pressurized cabins, paragraphs (a),
(b)(6), (c) and (d); 23.843, Pressurization tests; 23.1441, Oxygen
equipment and supply, paragraphs (c), (d) and (e); 23.1443, minimum
mass flow of supplemental oxygen, paragraphs (a), (b), and (c);
23.1445; Oxygen distribution system; 23.1447, Equipment standards for
oxygen dispensing units, paragraphs (a) through (d) and (f); 23.1449,
means of determining use of oxygen; and 23.1461, Equipment containing
high energy rotors. Current part 23 regulations contain prescriptive
language and means of compliance for the occupant physical environment
requirements. The FAA proposes to remove the specific requirements to
allow an applicant to specify the means of compliance for the physical
needs of the occupants including temperature, ventilation,
pressurization, supplemental oxygen, etc. For example, current Sec.
23.831(a) requires carbon monoxide not exceeding one part in 20,000
parts of air. The FAA proposes revising this by requiring breathable
atmosphere without hazardous concentrations of gases and vapors.
vi. Proposed Sec. 23.800, Fire Protection Outside Designated Fire
Zones
Proposed Sec. 23.800 would require that insulation on electrical
wire and electrical cable outside designated fire zones be self-
extinguishing. Proposed Sec. 23.800 would require airplane cockpit and
cabin materials in certification levels 1, 2, and 3 be flame-resistant.
Proposed Sec. 23.800 would require airplane cockpit and cabin
materials in certification level 4 airplanes be self-extinguishing.
Proposed Sec. 23.800 would also require that airplane materials in the
baggage and cargo compartments, which are inaccessible in flight and
outside designated fire zones, be self-extinguishing. Proposed Sec.
23.800 would require that any electrical cable installation that would
overheat in the event of circuit overload or fault be flame resistant.
Additionally, proposed Sec. 23.800 would preclude thermal acoustic
materials outside designated fire zones from being a flame propagation
hazard. Proposed Sec. 23.800 would also require sources of heat that
are capable of igniting adjacent objects outside designated fire zones
to be shielded and insulated to prevent such ignition.
Proposed Sec. 23.800 would require airplane baggage and cargo
compartments, outside designated fire zones, to be located where a fire
would be visible to the pilots, or equipped with a fire detection
system and warning system, and be accessible for the manual
extinguishing of a fire, have a built-in fire extinguishing system, or
be constructed and sealed to contain any fire within the compartment.
Proposed Sec. 23.800 would require a means to extinguish any fire
in the cabin, outside designated fire zones, such that the pilot, while
seated, could easily access the fire extinguishing means, and for
certification levels 3 and 4 airplanes, passengers would have a fire
extinguishing means available within the passenger compartment. Where
flammable fluids or vapors might escape by leakage of a fluid system,
proposed Sec. 23.800 would require each area, outside designated fire
zones, be defined and have a means to make fluid and vapor ignition,
and the resultant hazard, if ignition occurs, improbable. Additionally,
proposed Sec. 23.800 would also require combustion heater
installations outside designated fire zones be protected from
uncontained fire.
Proposed Sec. 23.800 would capture the safety intent of current
Sec. Sec. 23.851, Fire extinguishers, paragraphs (a) and (b); 23.853,
Passenger and crew compartment interiors, Paragraphs (a), (d)(3)(i),
(d)(3)(iii) and (d)(3)(iv), (e), and (f); 23.855, Cargo and baggage
compartment fire protection; 23.856, Thermal/acoustic insulation
materials; 23.859, Combustion heater fire protection, paragraph (a);
23.863, Flammable fluid fire protection, paragraphs (a) and (d);
23.1359, Electrical system fire protection, paragraph (c); 23.1365,
Electric cables and equipment, paragraph (b); 23.1383, Taxi and landing
lights, paragraph (d); 23.1385, Position light system installation,
paragraph (d). It would also capture the safety intent of CS-VLA-853,
Compartment interiors. Proposed Sec. 23.800 would incorporate the
requirements for flammability of all subpart D and F systems and
equipment outside designated fire zones needed for continued safe
flight and landing and remove specified design solutions and means of
compliances.
vii. Proposed Sec. 23.805, Fire Protection in Designated Fire Zones
Proposed Sec. 23.805 would require flight controls, engine mounts,
and other flight structures within or adjacent to designated fire zones
be capable of withstanding the effects of a fire. Proposed Sec. 23.805
would require engines inside designated fire zones to remain attached
to the airplane in the event of a fire or electrical arcing. Proposed
Sec. 23.805 would also require terminals, equipment, and electrical
cables, inside designated fire zones, used during emergency procedures,
be fire-resistant.
Proposed Sec. 23.805 would capture the safety intent of current
Sec. 23.865, Fire protection of flight controls, engine mounts, and
other flight structure and Sec. 23.1359(b), Electrical system fire
protection. The intent of proposed Sec. 23.805 is to protect flight
controls, engine mounts, and other flight structure as well as
electrical cables,
[[Page 13483]]
terminals and equipment from the effects of fire in designated fire
zones.
viii. Proposed Sec. 23.810, Lightning Protection of Structure
Proposed Sec. 23.810 would preclude primary structure failure
caused by exposure to the direct effects of lightning, that could
prevent continued safe flight and landing for airplanes approved for
IFR. Proposed Sec. 23.810 would require airplanes approved only for
VFR to achieve lightning protection by following FAA accepted design
practices found in FAA issued advisory circulars and in FAA accepted
consensus standards.
Proposed Sec. 23.810 would capture the safety intent of the
current Sec. 23.867(a) and (c), Electrical bonding and protection
against lightning and static electricity. The FAA proposes adopting the
structure requirements in part 23, amendment 23-7 (34 FR 13078, August
13, 1969), to limit the rule to protection of primary structure from
direct effects of lightning.
ix. Reorganization of Subpart D
The FAA proposes relocating the underlying safety. intent of
various subpart D sections with proposed sections in subparts B, C, F,
and G. The following table shows where the FAA proposes moving the
current subpart D sections in part 23.
----------------------------------------------------------------------------------------------------------------
Current section Title Proposed section Proposed title
----------------------------------------------------------------------------------------------------------------
23.601............................... General................ 23.500................. Structural design.
23.603............................... Materials and 23.500................. Structural design.
workmanship.
23.605............................... Fabrication methods.... 23.510................. Materials and
processes.
23.607............................... Fasteners.............. 23.505................. Protection of
structure.
23.609............................... Protection of Structure 23.505................. Protection of
structure.
23.611............................... Accessibility.......... 23.505................. Protection of
structure.
23.613............................... Material strength 23.510................. Materials and
properties and design processes.
values.
23.619............................... Special factors........ 23.515................. Special factors of
safety.
23.621............................... Casting factors........ 23.515................. Special factors of
safety.
23.623............................... Bearing factors........ 23.515................. Special factors of
safety.
23.625............................... Fitting factors........ 23.515................. Special factors of
safety.
23.627............................... Fatigue strength....... 23.405................. Structural durability.
23.629............................... Flutter................ 23.410................. Aeroelasticity.
23.641............................... Proof of strength...... Means of Compliance....
23.651............................... Proof of strength...... Means of Compliance....
23.655............................... Installation........... Means of Compliance....
23.657............................... Hinges................. 23.515................. Special factors of
safety.
23.659............................... Mass balance........... 23.315................. Flight load conditions.
23.671............................... Control Surfaces--
General.
(a).................................. ....................... 23.500................. Structural design.
(b).................................. ....................... 23.1305................ Function and
installation.
23.672............................... Stability augmentation 23.1305................ Function and
and automatic and installation.
power-operated systems.
23.673............................... Primary flight controls 23.1305................ Function and
installation.
23.675............................... Stops.................. 23.1305................ Function and
installation.
23.677............................... Trim systems...........
(a).................................. ....................... 23.700................. Flight control systems.
(b).................................. ....................... 23.700................. Flight control systems.
(c).................................. ....................... 23.410................. Aeroelasticity.
(d).................................. ....................... 23.700................. Flight control systems.
23.679............................... Control system locks... 23.1305................ Function and
installation.
23.681(a)............................ Limit load static tests 23.325(b).............. Component loading
conditions.
23.681(b)............................ Limit load static tests 23.515................. Special factors of
safety.
23.683............................... Operation tests........ 23.500(d).............. Structural design.
23.685(a), (b), (c).................. Control system details. 23.500(d).............. Structural design.
23.685(d)............................ Control system details. 23.1305................ Function and
installation.
23.687............................... Spring devices......... 23.410 and 23.500...... Aeroelasticity and
Structural design.
23.689............................... Cable systems.......... ....................... Component loading
conditions, Structural
design, and Equipment
Systems and
Installations.
(a).................................. ....................... 23.700................. Flight control systems.
(b).................................. ....................... 23.325(b), 23.500(d)... Component loading
conditions, Structural
design.
(c).................................. ....................... 23.325(b), 23.500(d)... Component loading
conditions, Structural
design.
(d).................................. ....................... 23.325(b), 23.500(d)... Component loading
conditions, Structural
design.
(e).................................. ....................... 23.325(b), 23.500(d)... Component loading
conditions, Structural
design.
(f).................................. ....................... 23.700................. Flight control systems.
23.691............................... Artificial stall
barrier system.
(a).................................. ....................... 23.700................. Flight control systems.
(b).................................. ....................... 23.700................. Flight control systems.
(c).................................. ....................... 23.1305................ Function and
installation.
(d).................................. ....................... 23.700................. Flight control systems.
(e).................................. ....................... 23.700................. Flight control systems.
(f).................................. ....................... 23.700................. Flight control systems.
(g).................................. ....................... 23.1315................ Equipment, systems and
Installations.
23.693............................... Joints................. 23.515................. Special factors of
safety.
[[Page 13484]]
23.697............................... Wing flap controls.....
(a).................................. ....................... 23.700................. Flight control systems.
(b) and (c).......................... ....................... 23.200................. Controllability.
23.699............................... Wing flap position 23.1500................ Flightcrew interface.
indicator.
23.701............................... Flap interconnection... Means of Compliance....
23.703............................... Takeoff warning system.
(a).................................. ....................... 23.700................. Flight control systems.
(b).................................. ....................... 23.700................. Flight control systems.
(c).................................. ....................... Definition.............
23.721............................... General................ 23.910................. Powerplant installation
hazard assessment.
23.723............................... Shock absorption tests. Means of Compliance....
23.725............................... Limit drop tests....... Means of Compliance....
23.726............................... Ground load dynamic Means of Compliance....
tests.
23.727............................... Reserve energy Means of Compliance....
absorption drop tests.
23.729............................... Landing gear extension
and retraction system.
(a).................................. ....................... 23.705................. Landing gear systems.
(b).................................. ....................... 23.705................. Landing gear systems.
(c).................................. ....................... 23.705................. Landing gear systems.
(d).................................. ....................... Means of Compliance....
(e).................................. ....................... 23.705................. Landing gear systems.
(f).................................. ....................... 23.1315................ Equipment, systems and
installation.
(g).................................. ....................... Means of Compliance....
23.731............................... Wheels................. 23.705................. Landing gear systems.
23.733............................... Tires..................
(a).................................. ....................... 23.705................. Landing gear systems.
(b).................................. ....................... Means of Compliance....
(c).................................. ....................... Means of Compliance....
23.735............................... Brakes................. 23.705.................
(a).................................. ....................... 23.705................. Landing gear systems.
(1).................................. ....................... Means of Compliance....
(2).................................. ....................... Means of Compliance....
(b).................................. ....................... 23.705................. Landing gear systems.
(c).................................. ....................... Means of Compliance....
(d).................................. ....................... 23.1315................ Equipment, systems and
installation.
(e).................................. ....................... 23.705................. Landing gear systems.
(1).................................. ....................... Means of Compliance....
(2).................................. ....................... Means of Compliance....
23.737............................... Skis................... 23.705................. Landing gear systems.
23.745............................... Nose/Tail wheel 23.1500................ Flightcrew interface.
steering.
23.751............................... Main float buoyancy....
(a).................................. ....................... 710.................... Buoyancy for seaplanes
and amphibians.
(b).................................. ....................... Means of Compliance....
23.753............................... Main float design...... 23.320................. Ground and water load
conditions.
23.755............................... Hulls.................. 23.710................. Buoyancy for seaplanes
and amphibians.
23.757............................... Auxiliary floats....... 23.710................. Buoyancy for seaplanes
and amphibians.
23.771............................... Pilot compartment......
(a).................................. ....................... 23.1500................ Flightcrew interface.
(b).................................. ....................... 23.755................. Occupant physical
environment.
(c )................................. ....................... 23.755................. Occupant physical
environment.
23.773............................... Pilot compartment view.
(a).................................. ....................... 23.1500................ Flightcrew interface.
(b).................................. ....................... 23.755................. Occupant physical
environment.
23.775............................... Windshields and windows
(a), (b), (c), (d)................... ....................... 23.755................. Occupant physical
environment.
(e).................................. ....................... Means of Compliance....
(f).................................. ....................... 23.1405................ Flight in icing
conditions.
(g).................................. ....................... Means of Compliance....
(h).................................. ....................... 23.755................. Occupant physical
environment.
23.777............................... Cockpit controls....... 23.1500................ Flightcrew interface.
23.779............................... Motion and effect of 23.1500................ Flightcrew interface.
cockpit controls.
23.781............................... Cockpit control knob 23.1500................ Flightcrew interface.
shape.
23.783............................... Doors..................
(a), (b), (c), (d)................... ....................... 23.750................. Means of egress and
emergency exits.
(e), (f), (g)........................ ....................... Means of Compliance....
23.785............................... Seats, berths, litters, 23.600 and 23.515...... Special factors of
safety belts, and safety, Emergency
shoulder harnesses. landing conditions.
23.787............................... Baggage and cargo 23.600(e).............. Emergency landing
compartments. conditions.
23.791............................... Passenger information 23.755................. Occupant physical
signs. environment.
23.803............................... Emergency evacuation...
[[Page 13485]]
(a).................................. ....................... 23.750................. Means of egress and
emergency exits.
(b).................................. ....................... Means of Compliance....
23.805............................... Flightcrew emergency 23.750................. Means of egress and
exits. emergency exits.
23.807............................... Emergency exits........
(a)(3 ), (b)(1), (c), (d)(1), (d)(4). ....................... Means of Compliance....
Balance of 23.807.................... ....................... 23.750................. Means of egress and
emergency exits.
23.811............................... Emergency exit marking. 23.750................. Means of egress and
emergency exits.
23.812............................... Emergency lighting..... 23.750................. Means of egress and
emergency exits.
23.813............................... Emergency exit access..
(a).................................. ....................... 23.750................. Means of egress and
emergency exits.
(b).................................. ....................... Means of Compliance....
CS-VLA 853........................... ....................... 23.750................. Means of egress and
emergency exits.
23.815............................... Width of aisle......... 23.750................. Means of egress and
emergency exits.
23.831............................... Ventilation............ 23.755................. Occupant physical
environment.
23.841(a), (b)(6), (c), (d).......... Pressurized cabins..... 23.755................. Occupant physical
environment.
(b)(1) through (5) and (7)........... ....................... Means of Compliance....
23.843............................... Pressurization tests... 23.755................. Occupant physical
environment.
23.851............................... Fire extinguishers.....
(a) and (b).......................... ....................... 23.800................. Fire protection outside
designated fire zones.
(c).................................. ....................... Means of Compliance....
23.853............................... Passenger and crew
compartment interiors.
(a).................................. ....................... 23.800................. Fire protection outside
designated fire zones.
(b)(c) and (d)(1)(2)................. ....................... Means of Compliance....
(d)(3)(i), (d)(3)(iii), (d)(3)(iv)... ....................... 23.800................. Fire protection outside
designated fire zones.
(e).................................. ....................... 23.800................. Fire protection outside
designated fire zones.
(f).................................. ....................... 23.800................. Fire protection outside
designated fire zones.
23.855............................... Cargo and baggage 23.800................. Fire protection outside
compartment fire designated fire zones.
protection.
23.856............................... Thermal/acoustic 23.800................. Fire protection outside
insulation materials. designated fire zones.
23.859............................... Combustion heater fire
protection.
(a).................................. ....................... 23.800................. Fire protection outside
designated fire zones.
(b) thru (i)......................... ....................... Means of Compliance....
23.863............................... Flammable fluid fire
protection.
(a) and (d).......................... ....................... 23.800................. Fire protection outside
designated fire zones.
(b) and (c).......................... ....................... Means of Compliance.... Fire protection outside
designated fire zones.
23.865............................... Fire protection of 23.805................. Fire protection in
flight controls, designated fire zones.
engine mounts, and
other flight structure.
23.867............................... Electrical bonding and
protection against
lightning and static
electricity.
(a), (c)............................. ....................... 23.810................. Lightning protection of
structure.
(b).................................. ....................... 23.1320................ Electrical and
electronic system
lightning protection.
23.871............................... Leveling means......... Means of Compliance....
----------------------------------------------------------------------------------------------------------------
5. Subpart E--Powerplant
a. General Discussion
The FAA proposes substantial changes to subpart E based on two
considerations. First, many of the current regulations could be
combined to provide fewer regulations that accomplish the same safety
intent. Second, part 23 overlaps with the requirements in parts 33 and
35. Refer to appendix 1 of this preamble for a cross-reference table
detailing how the current regulations are addressed in the proposed
part 23 regulations.
b. Specific Discussion of Changes
i. Proposed Sec. 23.900, Powerplant Installation
Proposed Sec. 23.900 would clarify, for the purpose of this
subpart, that the airplane powerplant installation must include each
component necessary for propulsion, affects propulsion safety, or
provides auxiliary power to the airplane. Proposed Sec. 23.900 would
require the applicant to construct and arrange each powerplant
installation to account for likely hazards in operation and maintenance
and, except for simple airplanes,\24\ each aircraft engine would have
to be type certificated.
---------------------------------------------------------------------------
\24\ Refer to Section III, Discussion of Proposal, paragraphs A
and B of this NPRM for definition and discussion of a simple
airplane.
---------------------------------------------------------------------------
Proposed Sec. 23.900 would capture the safety intent of current
Sec. Sec. 23.901, Installation, paragraphs (a), (b), and (f); 23.903,
Engines, paragraph (a); 23.905, Propellers, paragraph (a), 23.909,
Turbocharger systems, paragraphs (a) and (c); and 23.925, Propeller
clearance. Proposed Sec. 23.900 would combine the installation
requirements that are scattered throughout the subpart into a
[[Page 13486]]
general requirement for installation, and remove any duplication with
part 33. The following table illustrates the duplication between the
current part 23 regulations and part 33 requirements:
------------------------------------------------------------------------
Part 23 Part 33
------------------------------------------------------------------------
Sec. 23.901(d), Installation......... Sec. 33.33, Vibration.
Sec. 23.901(e), Installation......... Sec. 33.1, Applicability.
Sec. 23.934, Turbojet and turbofan Sec. 33.97, Thrust reversers.
engine thrust reverser systems tests.
Sec. 23.939, Powerplant operating Sec. Sec. 33.61 thru 33.79.
characteristics.
Sec. 23.1011, Oil System--General.... Sec. Sec. 33.39 and 33.71,
Lubrication system.
Sec. 23.1013(a) and (d), Oil tanks... Sec. Sec. 33.39, and 33.71,
Lubrication system.
Sec. 23.1015, Oil tank tests......... Sec. 33.33, Vibration.
Sec. 23.1023, Oil radiators.......... Sec. 33.33, Vibration.
Sec. 23.1041, Cooling--General....... Sec. 33.1, Applicability.
Sec. 23.1043, Cooling tests.......... Sec. Sec. 33.41 and 33.81,
Applicability--Block Tests.
Sec. 23.1045, Cooling test procedures Sec. 33.81, Applicability--
for turbine engine powered airplanes. Block Tests.
Sec. 23.1047, Cooling test procedures Sec. 33.35, Fuel and
for reciprocating engine powered induction system.
airplanes.
Sec. 23.1061, Liquid Cooling-- Sec. 33.21, Engine cooling.
Installation.
Sec. 23.1063, Coolant tank tests..... Sec. 33.41 and 33.81,
Applicability--Block Tests.
Sec. 23.1093, Induction system icing Sec. Sec. 33.35(b), Fuel and
protection. induction system and 33.68,
Induction system icing.
Sec. 23.1099, Carburetor deicing Sec. 33.35, Fuel and
fluid system detail design. induction system.
------------------------------------------------------------------------
Additionally, proposed Sec. 23.900 would identify the scope of the
powerplant installation in the same manner as the current requirements.
However, the FAA would redefine several terms to allow for alternate
sources of propulsion, such as electric motors. The FAA considers the
term powerplant to include all equipment used by the airplane that
provides propulsion or auxiliary power. The word engine would be
replaced with the term power unit and would include other power sources
driven by fuel such as liquid fuel, electrical, or other power sources
not yet envisioned. This proposal also predicates that each airplane
power unit or propeller receive a type certificate as a prerequisite
for installation, with the exception of simple airplanes. The current
part 33 airworthiness standards did not envision providing
certification requirements for types of engines outside of those that
operate on fossil fuels. As such, the ability of an applicant to obtain
the required engine type certificate for an alternate fuel type may be
impractical. For those power units, the FAA proposes to include them in
the airplane certification, which could include the use of an ELOS to
part 23. The FAA would expect an applicant to utilize all the
requirements listed in part 33 as a baseline matrix to find compliance
for an alternate powerplant type and for those requirements that could
not be met. Also, Sec. 21.16, Special conditions, may apply. It should
be noted that additional requirements might also be necessary due to an
absence of a corresponding part 33 requirement. This matrix would
become part of the certification baseline and recorded in an issue
paper as an ELOS, exemption, or special condition. Also, simple
airplanes will follow the precedence set for CS-VLA and will maintain
the exception to the requirement to be type certificated.
ii. Proposed Sec. 23.905, Propeller Installation
Proposed Sec. 23.905 would retain the requirement that each
propeller be type certificated, except for simple airplanes. Proposed
Sec. 23.905 would retain the requirement that each pusher propeller be
marked so that it is conspicuous under daylight conditions. All the
other requirements of the current section either duplicate part 35
standards, or would condense into the other requirements proposed in
Sec. Sec. 23.900, Powerplant installation; 23.910, Powerplant
installation hazard assessment; and 23.940, Powerplant ice protection.
iii. Proposed Sec. 23.910, Powerplant Installation Hazard Assessment
Proposed Sec. 23.910 would require an applicant to assess each
powerplant separately and in relation to other airplane systems and
installations to show that a failure of any powerplant system component
or accessory will not--
Prevent continued safe flight and landing;
Cause serious injury; and
Require immediate action by crewmembers for continued
operation of any remaining powerplant system.
Proposed Sec. 23.910 would capture the safety intent of current
Sec. Sec. 23.721, Landing gear--General; 23.903, Engines, paragraph
(c); 23.905, Propellers, paragraph (h); 23.909, Turbocharger systems,
paragraph (b), (c), and (e); 23.933 Reversing systems, paragraph (b);
23.937, Turbopropeller-drag limiting systems, paragraph (a); 23.959,
Unusable fuel supply; 23.979, Pressure fueling systems, paragraphs (c)
and (d); 23.991, Fuel pumps, paragraph (d); 23.994, Fuel system
components; 23.1001, Fuel jettisoning system, paragraph (h); 23.1027,
Propeller feathering system; 23.1111, Turbine engine, paragraph (a) and
(c); 23.1123, Exhaust system; 23.1125 Exhaust heat exchangers,
paragraph (a); 23.1142, Auxiliary power unit controls, paragraphs (d)
and (e); 23.1155, Turbine engine reverse thrust and propeller pitch
settings below the flight regime; 23.1163, Powerplant accessories,
paragraphs (b) and (d); 23.1191, Firewalls, paragraph (f); 23.1193,
Cowling and nacelle, paragraphs (f) and (g); 23.1201, Fire
extinguishing systems materials, paragraph (a); and 23.1203, Fire
detector system, paragraphs (b) and (c).
The proposed standard would reduce the repetitive requirements
found throughout the subpart and create one general powerplant
requirement to analyze and mitigate hazards associated with the
powerplant installation. For example, current Sec. 23.903(b)(1)
requires that design precautions be taken to minimize the hazards to
the airplane in the event of an engine rotor failure or a fire
originating inside the engine that could burn though the engine case.
These are very specific failure conditions, but are actually only two
small categories of many engine failure
[[Page 13487]]
conditions an applicant must assess. Section 23.903(c) requires that
multiple engines must be isolated from one another so a malfunction of
one engine does not affect the operation of the other. This is a
general analysis technique frequently called common mode analysis that
should apply to all powerplant components and include other critical
airplane systems that are not powerplant related, but could be affected
by a powerplant failure. Hazards the FAA proposes to remove from other
regulations and which would be addressed in this proposed section
include, but are not limited to, fire, ice, rain and bird ingestion,
rotorburst, engine case burn through, and flammable leakage.
iv. Proposed Sec. 23.915, Automatic Power Control Systems
Proposed Sec. 23.915 would require a power or thrust augmentation
system that automatically controls the power or thrust on the operating
powerplant to provide an indication to the flightcrew when the system
is operating; provide a means for the pilot to deactivate the automatic
functions; and prevent inadvertent deactivation.
Proposed Sec. 23.915 would capture the safety intent of current
Sec. 23.904, Automatic power reserve system and appendix H to part
23--Installation of An Automatic Power Reserve (APR) System. To foster
the growth and approval of technological advances, the FAA believes
that the detailed and prescriptive language of appendix H is more
appropriate as means of compliance. We would also include requirements
for thrust augmenting systems into this proposed section since there
seems to be a trend in general aviation to provide thrust management
systems more sophisticated than historical automatic power reserve
systems.
v. Proposed Sec. 23.920, Reversing Systems
Proposed Sec. 23.920 would require an airplane to be capable of
continued safe flight and landing under any available reversing system
setting, and would capture the safety intent of current Sec. 23.933(a)
and (b). The current rule includes a separate requirement for a
propeller reversing system that would be covered in the more general
language of the proposed section and applied to any type of reverser
system. Current Sec. 23.933 also requires an analysis of the system
for a failure condition. Those provisions would be addressed in the
general analysis requirements of proposed Sec. 23.910.
vi. Proposed Sec. 23.925, Powerplant Operational Characteristics
Proposed Sec. 23.925 would require the powerplant to operate at
any negative acceleration that could occur during normal and emergency
operation within the airplane operating limitations. Proposed Sec.
23.925 would require the pilot to have the capability to stop and
restart the powerplant in flight. Proposed Sec. 23.925 would require
the airplane to have an independent power source for restarting each
powerplant following an in-flight shutdown.
Proposed Sec. 23.925 would capture the safety intent of current
Sec. Sec. 23.903, Engines, paragraph (d), (e), (f), and (g); 23.939,
Powerplant operating characteristics; and 23.943, Negative
acceleration. Current Sec. 23.939 addresses powerplant operating
characteristics and clearly requires an analysis that would be required
by proposed Sec. 23.910 and the existing requirements of part 33.
Current Sec. 23.943 would be included in this proposed rule because it
is another analysis requirement, and one that provides an environment
where powerplant systems are required to operate.
vii. Proposed Sec. 23.930, Fuel Systems
Proposed Sec. 23.930 would require that each fuel system provide
an independent fuel supply to each powerplant in at least one
configuration and prevent ignition from an unknown source. This section
would require that each fuel system provide the fuel required to
achieve maximum power or thrust plus a margin for likely variables in
all temperature conditions within the operating envelope of the
airplane and provide a means to remove the fuel from the airplane.
Proposed Sec. 23.930 would require each fuel system to be capable of
retaining fuel when subject to inertia loads under expected operating
conditions and prevent hazardous contamination of the fuel supply.
Proposed Sec. 23.930 would require each fuel storage system to
withstand the loads and pressures under expected operating conditions
and provide a means to prevent loss of fuel during any maneuver under
operating conditions for which certification is requested. Also,
proposed Sec. 23.930 would require each fuel storage system to prevent
discharge when transferring fuel, provide fuel for at least one-half
hour of operation at maximum continuous power or thrust, and be capable
of jettisoning fuel, if required for landing.
Proposed Sec. 23.930 would require installed pressure refueling
systems to have a means to prevent the escape of hazardous quantities
of fuel, automatically shut-off before exceeding the maximum fuel
quantity of the airplane, and provide an indication of a failure at the
fueling station. Proposed Sec. 23.930 would capture the safety intent
of current Sec. Sec. 23.951, Fuel System--General, paragraphs (a),
(b), (c), and (d); 23.953, Fuel System; 23.954, Fuel system lightning
protection; 23.955, Fuel flow; 23.957, Flow between interconnected
tanks, paragraph (a); 23.961, Fuel system hot weather operation;
23.963, Fuel tanks: General, paragraphs (a), (d), and (e); 23.977, Fuel
tank outlet; 23.979, Pressure fueling systems, paragraphs (a) and (b);
23.991, Fuel pumps, paragraphs (a), (b), and (c); 23.997, Fuel strainer
or filter, paragraphs (a), (b), (c), and (d); 23.999, Fuel system
drains; and 23.1001, Fuel jettisoning system, paragraph (a).
The FAA believes that the regulations for the design of fuel
systems may be overly prescriptive and exceed what is necessary to
design a safe system. Accordingly, a more general set of requirements
could include the intent of many current rules. More importantly, this
proposed rule would allow for other types of energy sources to power
propulsion systems such as electrical motors and future energy sources.
viii. Proposed Sec. 23.935, Powerplant Induction and Exhaust Systems
Proposed Sec. 23.935 would require the air induction system to
supply the air required for each power unit and its accessories under
expected operating conditions, and provide a means to discharge
potential harmful material. Proposed Sec. 23.935 would capture the
safety intent of current Sec. Sec. 23.1091, Air induction system,
paragraph (a); 23.1101, Induction air preheater design, paragraph (a);
23.1103, Induction system ducts; 23.1107, Induction system filters; and
23.1121, Exhaust System--General, paragraphs (a) through (g). This
proposed rule would combine induction and exhaust systems into a single
rule because of the commonality with issues associated with moving air.
The prescriptive language of the regulations identified above in this
paragraph drove the development of this proposed section. For example,
Sec. 23.1091(b) mandates a certain number of intake sources and
specifies particular requirements for a primary and alternate intakes.
Current Sec. 23.1101 requires inspection access of critical parts, and
current Sec. 23.1103 is considered a part of a proper safety analysis
that would be required by proposed Sec. 23.910.
[[Page 13488]]
ix. Proposed Sec. 23.940, Powerplant Ice Protection
Proposed Sec. 23.940 would require the airplane design, including
the engine induction system, to prevent foreseeable accumulation of ice
or snow that would adversely affect powerplant operation. Proposed
Sec. 23.940 would also require the applicant design the powerplant to
prevent any accumulation of ice or snow that would adversely affect
powerplant operation, in those icing conditions for which certification
is requested. Proposed Sec. 23.940 would capture the safety intent of
current Sec. Sec. 23.905, Propellers, paragraph (e); 23.929, Engine
installation ice protection; 23.975, Fuel tank vents and carburetor
vapor vents, paragraph (a)(1); 23.1093, Induction system icing
protection; 23.1095, Carburetor deicing fluid flow rate; 23.1097,
Carburetor deicing fluid system capacity; and 23.1099, Carburetor
deicing fluid system detail design.
Proposed Sec. 23.940(a) would reflect the requirements in current
Sec. 23.1093, which applies to all airplanes, regardless if flight in
icing certification is sought. We are proposing to remove the type of
powerplant to accommodate for new powerplant technologies. In addition,
we propose to define other foreseeable icing in the means of
compliance, which would include conditions conducive to induction icing
of reciprocating engines. Foreseeable icing in the means of compliance
would also include the cloud icing conditions of appendix C to part 25,
currently defined in Sec. 23.1093(b)(1)(i), falling and blowing snow
currently defined in Sec. 23.1093(b)(1)(ii), and ground ice fog
conditions currently defined in Sec. 23.1093(b)(2). The FAA proposes
to remove the prescriptive requirements of the current Sec. Sec.
23.1093(a), 23.1095, 23.1097, and 23.1099 as these are more
appropriately considered as means of compliance. The FAA would expect
the means of compliance to expand the ground ice fog conditions to
colder ambient temperatures to harmonize with EASA. The FAA would also
expect the means of compliance to include optional ground and flight
freezing drizzle and freezing rain conditions, similar to appendix O of
part 25, for those airplanes that seek certification to operate in
those conditions. The Part 23 Icing ARC had recommended specific pass/
fail criteria for the effect of ice accretion on engine operation. The
FAA would expect this criterion to be defined in a means of compliance.
Proposed paragraph (a) would require an airplane design to prevent
``foreseeable'' ice or snow accumulation, including accumulation in
inadvertent icing encounters, described in appendix C to part 25, on
airplanes not certified for icing, which may pose a shed hazard to the
powerplant.
Airplane design in proposed Sec. 23.940(a) refers to the engine
induction system and airframe components on which accumulated ice may
shed into the powerplant. Powerplant design in proposed Sec. 23.940(b)
refers to the engine, propeller, and other powerplant components such
as cooling inlets.
Proposed Sec. 23.940(b) would apply only to airplanes certified
for flight in icing and would require compliance to the icing
requirements in part 33, which currently only apply to turbine engines.
Part 33, amendment 33-34 (79 FR 65507, November 4, 2014) and effective
January 5, 2015, added SLD and ice crystal requirements to Sec. 33.68
and amended the engine ice ingestion requirements in Sec. 33.77.
Proposed Sec. 23.940(b) would require installation of an engine(s)
certified to Sec. 33.68 amendment 33-34, or later, if the airplane
will be certified for flight in freezing drizzle and freezing rain.
Proposed Sec. 23.940(b) would allow an airplane manufacturer to
install an engine, type certified at an earlier amendment, in an
airplane not certified for flight in freezing drizzle or freezing rain,
as long as no ADs have been applied that relate to engine operation in
inadvertent SLD or ice crystal conditions. Airplanes certified under
part 23 have not had ADs related to SLD or ice crystals. Certain part
23 turbojet engines have experienced thrust rollback due to ice
crystals blocking the heated inlet temperature probe. The FAA would
expect the means of compliance to address this in a similar manner to
what is accomplished on current certification projects. The engine ice
ingestion requirements of the current Sec. 23.903(a)(2) would be moved
to proposed Sec. 23.940(b).
x. Proposed Sec. 23.1000, Powerplant Fire Protection
Proposed Sec. 23.1000 would require that a powerplant only be
installed in a designated fire zone and would require an applicant to
install a fire detection system in each designated fire zone for
certification levels 3 and 4 airplanes. This rulemaking effort is
maintaining the current level of safety for fire protection. While not
a perfect one-to-one relationship, airplanes equivalent to
certification levels 1 and 2 airplanes are not required to have a fire
detection system today and therefore, should not be required to have
them in this proposed rule. This would increase the cost of
certification. Each fire detection system would be required to provide
a means to alert the flightcrew in the event of a detection of fire or
failure of the system and a means to check the fire detection system in
flight. Proposed Sec. 23.1000 would also require an applicant to
install a fire extinguishing system for certification levels 2, 3, and
4 airplanes with a powerplant located outside the pilot's view that
uses combustible fuel.
Additionally, proposed Sec. 23.1000 would require each component,
line, and fitting carrying flammable fluids, gases, or air subject to
fire conditions to be fire resistant, except components storing
concentrated flammable material would have to be fireproof or enclosed
by a fireproof shield. Proposed Sec. 23.1000 would also require an
applicant to provide a means to shut off fuel or flammable material for
each powerplant, while not restricting fuel to remaining units, and
prevent inadvertent operation. Proposed Sec. 23.1000 would capture the
safety intent of current Sec. Sec. 23.1181, Designated fire zones:
Regions included; 23.1182, Nacelle areas behind firewalls; 23.1183,
Lines, fittings, and components; 23.1189, Shutoff means; 23.1191,
Firewalls; 23.1192 Engine accessory compartment diaphragm; 23.1193,
Cowling and nacelle; 23.1195, Fire extinguishing systems; 23.1197, Fire
extinguishing agents; 23.1199, Extinguishing agent containers; 23.1201,
Fire extinguishing system materials; and 23.1203, Fire detector system.
Regulations for fuel may have become too detailed and prescriptive.
A more general set of requirements should capture the intent of these
many rules. More importantly, this new proposed rule would allow other
types of energy sources to power propulsion systems such as electrical
motors and future energy sources.
xi. Current Subpart E Regulations Relocated to Other Proposed Subparts
The requirements of current Sec. 23.903(b)(1) would be moved to
subpart C, Sec. 23.405, Structural durability, paragraph (d). Section
23.903(b)(1) requires design precautions for turbine engine
installations to be taken to minimize hazards to the airplane in the
event of an engine rotor failure or of a fire originating inside the
engine which burns through the engine case.
Additionally, the requirements of current Sec. 23.929 would be
moved to proposed Sec. 23.940(b) and would only apply to airplanes
certified for flight in icing. The means of compliance for Sec.
23.940(b) should address propeller ice
[[Page 13489]]
protection system design and analysis. However, the means of compliance
for climb performance for proposed Sec. 23.230 should address ice
accretion effects on propeller performance on airplanes certified for
flight in icing.
xii. Removal of Subpart E Current Regulations
The following current regulations are considered duplicative of
part 35 and would be removed from subpart E: Sec. 23.905(b)--
duplicative of Sec. 35.5, Propeller ratings and operation limitations;
Sec. 23.905(c)--duplicative of Sec. 35.22, Feathering propellers;
Sec. 23.905(d)--duplicative of Sec. Sec. 35.21, 35.23, 35.42 and
35.43; and Sec. 23.905(e)(g) and (h)--duplicative of Sec. 35.7,
Features and characteristics.
6. Subpart F--Equipment
a. General Discussion
The proposed changes to subpart F would consolidate the current
rules into new performance-based standards and allow for use of new
technologies once consensus standards are developed that could be used
as a means of compliance.The FAA believes the proposed part 23
requirements would maintain the current level of safety while staying
relevant for new future technologies. The prescriptive design solutions
in the current rules are often not relevant to new technology requiring
special conditions, exemptions, and ELOS findings. The rate of new
technology development and adoption has increased dramatically in the
last decade. As a result, airplane systems with new features and
capabilities are rapidly becoming available. The FAA believes that
removing the prescriptive design solutions, which are based on outdated
or existing technology, while focusing on the safety intent of the rule
and maintaining design solutions as a documented means of compliance
would enable the adoption of newer technologies.
The FAA also believes the current part 23 regulatory prescriptive
structure does not effectively address the safety continuum,
particularly the low performance end of the continuum. Recent part 23
amendments have increasingly focused on high-performance, complex
airplanes. These stricter requirements have also been applied to the
low-performance airplanes even though their risk in the safety
continuum is lower. This has created an unintended barrier to new
safety enhancing technology in low-performance airplanes.
b. Specific Discussion of Changes
i. Proposed Sec. 23.1300, Airplane Level Systems Requirements
Proposed Sec. 23.1300 would require equipment and systems that are
required for an airplane to operate safely, be designed and installed
to meet the level of safety applicable to the certification and
performance levels of the airplane, and to perform their intended
function throughout the operating and environmental limits specified by
an applicant. Proposed Sec. 23.1300 would mandate that
non[hyphen]required airplane equipment and systems, considered
separately and in relation to other systems, be designed and installed
so their operation or failure would not have an adverse effect on the
airplane or its occupants.
Proposed Sec. 23.1300 would capture the safety intent found in
portions of current Sec. Sec. 23.1301, Function and installation;
23.1303, Flight and navigation instruments; 23.1305, Powerplant
instruments; 23.1307, Miscellaneous equipment; 23.1309, Equipment,
systems, and installations; 23.1311, Electronic display instrument
systems; 23.1321, Arrangement and visibility; 23.1323, Airspeed
indicating system, 23.1325, Static pressure system; 23.1327, Magnetic
direction indicator; 23.1329, Automatic pilot system; 23.1335, Flight
director systems; 23.1337, Powerplant instruments installation;
23.1351, Electrical Systems and Equipment--General; 23.1353, Storage
battery design and installation; and 23.1361, Master switch
arrangement.
The current requirements can be traced back to CAR 3, specifically
CAR 3.651, 3.652, 3.655, 3.661, 3.662, 3.663, 3.665, 3.666, 3.667,
3.669, 3.670, 3.671, 3.672, 3.673, 3.674, 3.681, 3.682, 3.686, 3.687,
and 3.683. These requirements, including Sec. 23.1311, which does not
have a corresponding rule in CAR 3, were based on the technology and
design solutions available at the time of their adoption. Although
these requirements are appropriate for traditional systems found in
airplanes designed to these assumptions, they lack the flexibility to
adopt current and anticipated technologies and design capabilities. The
FAA wants to facilitate the use of systems in new airplanes that reduce
pilot workload and enhance safety. The FAA proposes the use of
performance-based language that maintains the level of safety achieved
with the current requirements for traditionally designed airplanes but
also allows for alternative system designs in the future.
Proposed Sec. 23.1300(a) would address equipment and systems
required to operate safely. Required equipment may be defined by other
parts such as part 91 or part 135, by other sections of this part such
as equipment necessary for flight into known icing, or other
requirements placed on the Type Certificate Data Sheet (TCDS) such as a
working autopilot for single pilot operations. The FAA proposes in
Sec. 23.1300(b) that non-required equipment may be installed because
it offers some benefit and its failure or use would not result in a
reduction in safety of the airplane or for its occupants from the base
aircraft if the system was not installed. This proposed section would
contain general requirements for the environmental qualifications of
installed equipment, and would require installed equipment to perform
its intended function over its defined environmental range. This would
mean that the equipment should have the same environmental
qualification as requested for the useful range of the airplane.
Proposed Sec. 23.1300(b) would not mandate that non-required
equipment and systems function properly during all airplane operations
once in service, provided all potential failure conditions do not
effect safe operation of the airplane. The equipment or system would
have to function in the manner expected by the manufacturer's operating
manual for the equipment or system. An applicant's statement of
intended function would have to be sufficiently specific and detailed
so that the FAA could evaluate whether the system was appropriate for
the intended function.
ii. Proposed Sec. 23.1305, Function and Installation
Proposed Sec. 23.1305 would require that each item of installed
equipment perform its intended function, be installed according to
limitations specified for that equipment, and the equipment be labeled,
if applicable, due to size, location, or lack of clarity as to its
intended function, as to its identification, function or operating
limitations, or any combination of these factors. Proposed Sec.
23.1305 would require a discernable means of providing system operating
parameters required to operate the airplane, including warnings,
cautions, and normal indications to the responsible crewmember.
Proposed Sec. 23.1305 would require information concerning an unsafe
system operating condition be provided in a clear and timely manner to
the crewmember responsible for taking corrective action.
[[Page 13490]]
Proposed Sec. 23.1305 would capture the safety intent found in
portions of the current Sec. Sec. 23.671, Control systems-General;
23.672, Stability augmentation and automatic and power-operated
systems; 23.673, Primary flight controls; 23.675, Stops; 23.679,
Control system locks; 23.685(d), Control system details; 23.691(c),
Artificial stall barrier system; 23.1361, Master switch arrangement;
and 23.1365(a) and (b), Electric cables and equipment; 23.1301,
Function and installation; 23.1303, Flight and navigation instruments;
23.1305, Powerplant instruments; 23.1309, Equipment, systems, and
installations; 23.1322, Warning, caution, and advisory lights; 23.1323,
Airspeed indicating system; 23.1326, Pitot heat indication systems;
23.1327, Magnetic direction indicator; 23.1329, Automatic pilot system;
23.1331, Instruments using a power source; 23.1335, Flight director
systems; 23.1337, Powerplant instruments installation; 23.1351,
Electrical Systems and Equipment--General; 23.1353, Storage battery
design and installation; 23.1365, Electric cables and equipment;
23.1367, Switches; 23.1416, Pneumatic de-icer boot system. The current
requirements can be traced to CAR 3, specifically, CAR 3.651, 3.652,
3.655, 3.663, 3.666, 3.667, 3.668, 3.669, 3.670, 3.671, 3.672, 3.673,
3.674, 3.675, 3.681, 3.682, 3.683, 3.686, 3.687, 3.693, 3.694, 3.696,
3.697, 3.700, 3.712, and 3.726. These requirements, including
Sec. Sec. 23.1322, 23.1326, and 23.1441, which did not have
corresponding rules in CAR 3, were based on the technology and design
solutions available at the time of their adoption. Although these
requirements are appropriate for traditional systems and designs found
in airplanes designed to these assumptions, they lack the flexibility
to adopt current and anticipated technologies and design capabilities.
The FAA wants to facilitate the use of systems in new airplanes that
reduce pilot workload and enhance safety. The FAA proposes the use of
performance-based language that maintains the safety requirements for
traditionally designed airplanes, but also allows for alternative
system designs.
The equipment or system would have to function in the manner
expected by the manufacturer's operating manual for the equipment or
system. An applicant's statement of intended function would have to be
sufficiently specific and detailed so that the FAA could evaluate
whether the system was appropriate for the intended function. The
equipment should function when installed as intended by the
manufacturer's instructions. The intent is for an applicant to define
proper functionality and to propose an acceptable means of compliance.
Proposed Sec. 23.1305(a) would require that equipment be installed
under prescribed limitations. Therefore, if an equipment manufacturer
specified any allowable installation requirements, the installer would
stay within the limitations or substantiate the new limits. The
proposed requirement that the equipment be labeled as to its
identification, function or operating limitations, or any combination
of these factors, if applicable, would apply to the manufacturer of the
equipment, not to the installer.
Proposed Sec. 23.1305 would require that information concerning an
unsafe system operating condition be provided to the flightcrew.
Microprocessing units that monitor parameters and warn of system
problems have already been incorporated in some airplanes and are used
by other industries, including the automobile and nuclear energy
fields. Pilots may not monitor gauges as they used to; instead, they
could rely on warnings and alerts. The FAA does not propose to allow
simple on-off failure lights to replace critical trend displays.
Warning systems would need to be sophisticated enough to read
transients and trends, when appropriate, and give useful warning to the
flightcrew.
iii. Proposed Sec. 23.1310, Flight, Navigation, and Powerplant
Instruments
Proposed Sec. 23.1310 would require installed systems to provide
the flightcrew member who sets or monitors flight parameters for the
flight, navigation, and powerplant information necessary to do so
during each phase of flight. Proposed Sec. 23.1310 would require this
information include parameters and trends, as needed for normal,
abnormal, and emergency operation, and limitations, unless an applicant
showed the limitation would not be exceeded in all intended operations.
Proposed Sec. 23.1310 would prohibit indication systems that integrate
the display of flight or powerplant parameters to operate the airplane
or are required by the operating rules of this chapter, from inhibiting
the primary display of flight or powerplant parameters needed by any
flightcrew member in any normal mode of operation. Proposed Sec.
23.1310 would require these indication systems be designed and
installed so information essential for continued safe flight and
landing would be available to the flightcrew in a timely manner after
any single failure or probable combination of failures.
Proposed Sec. 23.1310 would capture the safety intent of current
Sec. Sec. 23.1303, Flight and navigation instruments; 23.1305,
Powerplant instruments; 23.1307, Miscellaneous equipment; 23.1311,
Electronic display instrument systems; 23.1321, Arrangement and
visibility; 23.1323, Airspeed indicating system; 23.1331, Instruments
using a power source; and 23.1337, Powerplant instruments installation.
The current requirements can be traced to CAR 3, specifically, CAR
3.655, 3.661, 3.662, 3.675, 3.663, 3.668, 3.670, 3.671, 3.672, 3.673,
and 3.674. These requirements, including Sec. 23.1311, which did not
have a corresponding rule in CAR 3, were based on the technology and
design solutions available at the time of their adoption. Although
these requirements are appropriate for traditional systems and designs
found in airplanes designed to these assumptions, they lack the
flexibility to adopt current and anticipated technologies and design
capabilities. Furthermore, the FAA proposes to remove prescriptive
requirements from the rule that historically provided standardization
for primary flight instruments and controls. The FAA still believes
this standardization is important for traditionally designed airplane
instrumentation. Accordingly, to reduce the potential for pilot error,
the reliance on standards accepted by the Administrator would maintain
standardization for traditional systems.
The proposed regulations would require applicants to use a means of
compliance based on consensus standards or other means accepted by the
Administrator. However, new technology is already being approved that
does not meet the traditional installation requirements and guidance.
At the same time, this technology is proving equivalent or better than
the traditional technology.\25\ Furthermore, the FAA believes that new
systems, displays, and controls have the potential to reduce pilot
workload with a direct safety benefit. By removing prescriptive
requirements for the rules and allowing alternatives, the industry
would be able to develop and certify safety-enhancing technology
faster.
---------------------------------------------------------------------------
\25\ See Accident and GA Safety reports from NTSB, AOPA Safety
Foundation, and the General Aviation Joint Steering Committee (GA-
JSC) over the past 10 years.
---------------------------------------------------------------------------
Proposed Sec. 23.1310 would not require limitations that could not
be exceeded due to system design or physical properties to be shown
because they would be useless information and result in clutter of the
displays. Additionally, the FAA proposes removing the
[[Page 13491]]
prescriptive design requirement in current Sec. 23.1311 for the
installation of secondary indicators. The safety intent is that a
single failure or likely multiple failures would not result in the lack
of all critical flight data. The design and installation of flight
critical information should be such that the pilot could still fly
partial panel after probable failures. The prescriptive redundancy
requirements for installed secondary indicators have been too
restrictive for airplanes limited to VFR operations. This has caused
several applicants to request an ELOS finding from current Sec.
23.1311(a)(5).
The safety intent of Sec. 23.1311 is to provide crewmembers the
ability to obtain the information necessary to operate the airplane
safely in flight. Traditionally, the minimum was prescribed as
airspeed, altimeter, and magnetic direction. The corresponding CAR 3
rule is 3.655. The regulation is redundant with the operating rules,
specifically, Sec. Sec. 91.205 and 135.149, as well as providing
prescriptive design solutions that were assumed to achieve an
acceptable level of safety. The prescriptive solutions precluded
finding more effective or more economical paths to providing acceptable
safety. Proposed Sec. 23.1310 would maintain the safety intent of the
current rule.
The FAA proposes consolidating the safety intent of current Sec.
23.1305, Powerplant instruments, into proposed Sec. 23.1310, Flight,
Navigation, and Powerplant Instruments. The safety intent of Sec.
23.1305 is to provide crewmembers the ability to obtain the information
necessary to operate the airplane and powerplant safely in flight.
Traditionally, the minimum was prescribed, such as oil pressure, oil
temperature, and oil quantity for all airplanes. The corresponding
rules in CAR 3 are 3.655 and 3.675. Some of the regulation was
redundant with the operating rules as well as providing prescriptive
design solutions that were assumed to achieve an acceptable level of
safety based on an assumption of powerplant types. The prescriptive
solutions precluded finding more effective or more economical paths to
providing acceptable safety. Additionally, they do not facilitate
adoption of new technologies such as electric powered airplanes. The
proposed Sec. 23.1310, Flight, Navigation, and Powerplant Instruments,
would maintain the safety intent of the current rule.
iv. Proposed Sec. 23.1315, Equipment, Systems, and Installation
Proposed Sec. 23.1315 would require an applicant to examine the
design and installation of airplane systems and equipment, separately
and in relation to other airplane systems and equipment, for any
airplane system or equipment whose failure or abnormal operation has
not been specifically addressed by another requirement in this part.
Proposed Sec. 23.1315 would require an applicant to determine if a
failure of these systems and equipment would prevent continued safe
flight and landing and if any other failure would significantly reduce
the capability of the airplane or the ability of the flightcrew to cope
with adverse operating conditions. Proposed Sec. 23.1315 would require
an applicant to design and install these systems and equipment,
examined separately and in relation to other airplane systems and
equipment, such that each catastrophic failure condition is extremely
improbable, each hazardous failure condition is extremely remote, and
each major failure condition was remote. Proposed Sec. 23.1315 would
capture the safety intent found in portions of current Sec. Sec.
23.691(g), Artificial stall barrier system; 23.729(f), Landing gear
extension and retraction system; 23.735(d), Brakes; 23.1309, Equipment,
systems, and installations; 23.1323, Airspeed indicating system;
23.1325, Static pressure system; 23.1329, Automatic pilot system;
23.1331, Instruments using a power source; 23.1337, Powerplant
instruments installation; 23.1335, Flight director systems; 23.1353,
Storage battery design and installation, 23.1357, Circuit protective
devices; 23.1431, Electronic equipment; 23.1441(b), Oxygen equipment
and supply; 23.1450(b), Chemical oxygen generators; 23.1451, Fire
protection for oxygen equipment; and 23.1453, Protection of oxygen
equipment from rupture. The current requirements can be traced to CAR
3, specifically, 3.652, 3.663, 3.665, 3.667, 3.668, 3.670, 3.671,
3.672, 3.673, 3.674, and 3.683. The foundation of the current Sec.
23.1309 was derived from CAR 3.652, which stated that ``each item of
equipment, which is essential to the safe operation of the airplane,
shall be found by the Administrator to perform adequately the functions
for which it is to be used . . .''. At that time, the airworthiness
requirements were based on single-fault or fail-safe concepts. Due to
the increased use of airplanes certificated under part 23 in the 1970s
for all-weather operation, and a pilot's increased reliance on
installed avionic systems and equipment, Sec. 23.1309, amendment 23-14
(38 FR 31816, November 19, 1973), was issued to provide an acceptable
level of safety for such equipment, systems, and installations. Section
23.1309 introduced two main concepts: multiple failure combinations as
well as a single failure had to be considered and there must be an
inverse relationship between the likelihood of occurrence and the
severity of consequences. The premise was that more severe consequences
should happen less often.
In addition to specific part 23 design requirements, proposed Sec.
23.1315 requirements would apply to any equipment or system installed
in the airplane. This proposed section addresses general requirements
and is not intended to supersede any specific requirements contained in
other part 23 sections. Proposed Sec. 23.1315 would not apply to the
performance or flight characteristics requirements of subpart B, and
structural loads and strength requirements of subpart C and D. However,
it would apply to systems that complied with subpart B, C, D, and E
requirements. As an example, proposed Sec. 23.1315 would not apply to
an airplane's inherent stall characteristics, but would apply to a
stick pusher system installed to attain stall compliance. Both current
Sec. 23.1309 and proposed Sec. 23.1315 rules are not intended to add
requirements to specific rules in part 23, but to account for the added
complexity of integration and new technologies.
This proposed regulation would require an engineering safety
analysis to identify possible failures, interactions, and consequences,
and would require an inverse relationship between the probability of
failures and the severity of consequences. This would be accomplished
by requiring all of the airplane's systems to be reviewed to determine
if the airplane was dependent upon a system function for continued safe
flight and landing and if a failure of any system on the airplane would
significantly reduce the ability of the flightcrew to cope with the
adverse operating condition. If the design of the airplane included
systems that performed such functions, the systems would be required to
meet standards that establish that maximum allowable probability of
that failure. Section 23.1315 would impose qualitative, rather than
quantitative probabilities of occurrence. As the FAA determined which
quantitative values satisfied the proposed performance standards, it
would share that information in FAA guidance or documented means of
compliance appropriate to the certification levels of proposed Sec.
23.5.
[[Page 13492]]
v. Proposed Sec. 23.1320, Electrical and Electronic System Lightning
Protection
Proposed Sec. 23.1320 would require, for an airplane approved for
IFR operations, that each electrical or electronic system that
performed a function, the failure of which would prevent the continued
safe flight and landing of the airplane, be designed and installed such
that the airplane level function continues to perform during and after
the time the airplane is exposed to lightning. Proposed Sec. 23.1320
would also require these systems automatically recover normal operation
of that function in a timely manner after the airplane is exposed to
lightning, unless the system's recovery conflicts with other
operational or functional requirements of the system.
Proposed Sec. 23.1320 would require each electrical and electronic
system that performed a function, the failure of which would reduce the
capability of the airplane or the ability of the flightcrew to respond
to an adverse operating condition, be designed and installed such that
the function recovers normal operation in a timely manner after the
airplane is exposed to lightning.
Proposed Sec. 23.1320 would capture the safety intent of current
Sec. 23.1306, Electrical and electronic system lightning protection.
The original adoption of the rule, first introduced as part of Sec.
23.1309, was justified because there was an increased use of small
airplanes in all-weather operations with an increasing reliance on
complex systems and equipment in the modern, complex, high-performance
airplanes.
The FAA wants to facilitate the use of systems in new airplanes
that reduce pilot workload and enhance safety. The current requirement
that all aircraft regardless of their design or operational limitations
meet the same requirements for lightning regardless of the potential
threat has been burdensome for the traditional VFR-only airplane
designs. Proposed Sec. 23.1320 would cover the airplanes with the
greatest threat of lightning. In addition, the proposed language
clarifies that the failure consequence of interest is at the airplane
system level, which allows credit for design and installation
architecture.
vi. Proposed Sec. 23.1325, High-Intensity Radiated Fields (HIRF)
Protection
Proposed Sec. 23.1325 would require that electrical and electronic
systems that perform a function whose failure would prevent the
continued safe flight and landing of the airplane, be designed and
installed such that the airplane level function is not adversely
affected during and after the time the airplane is exposed to the HIRF
environment. Proposed Sec. 23.1325 would also require that these
systems automatically recover normal operation of that function in a
timely manner after the airplane is exposed to the HIRF environment,
unless the system's recovery conflicts with other operational or
functional requirements of the system. Proposed Sec. 23.1325, High-
Intensity Radiated Fields (HIRF) protection, would incorporate the
safety intent of current Sec. 23.1308, High-intensity Radiated Fields
(HIRF) protection.
Before Sec. 23.1308, amendment 23-57 (72 FR 44016, August 6,
2007), the requirements for HIRF protection were found in Sec.
23.1309. The adoption of Sec. 23.1308 was justified because there was
an increased use of complex systems and equipment, including engine and
flight controls, in small airplanes. These systems are more susceptible
to the adverse effects of operation in the HIRF environment.
The electromagnetic HIRF environment results from the transmission
of electromagnetic energy from radar, radio, television, and other
ground-based, ship-borne, or airborne radio frequency transmitters. The
HIRF environment changes as the number and types of transmitters
change. During the 1990's, extensive studies were conducted to define
the environment that then existed. The FAA codified this environment in
amendment 23-57 in appendix J to part 23--HIRF Environments and
Equipment HIRF Test Levels.
Proposed Sec. 23.1325 would require the applicant to address the
HIRF environment expected in service instead of solely relying on the
HIRF environment codified in appendix J. The current appendix J to part
23 would become a means of compliance as the accepted expected HIRF
environment, until other levels were accepted by the Administrator.
This would allow the test levels to match the current threat as the
environment changes over time. Additionally, the proposed language
would clarify that the failure consequence of interest is at the
airplane level, which allows credit for design and installation
architecture.
vii. Proposed Sec. 23.1330, System Power Generation, Storage, and
Distribution
Proposed Sec. 23.1330(a) would require that the power generation,
storage, and distribution for any system be designed and installed to
supply the power required for operation of connected loads during all
likely operating conditions. Also, proposed Sec. 23.1330(b) would
require the design installation ensure no single failure or malfunction
would prevent the system from supplying the essential loads required
for continued safe flight and landing. Proposed Sec. 23.1330 would
also require the design and installation have enough capacity to supply
essential loads, should the primary power source fail, for at least 30
minutes for airplanes certificated with a maximum altitude of 25,000
feet or less, and at least 60 minutes for airplanes certificated with a
maximum altitude over 25,000 feet.
Proposed Sec. 23.1330 would capture the safety intent of the
current Sec. Sec. 23.1310, Power source capacity and distribution;
23.1351, General; 23.1353, Storage battery design and installation; and
23.1357, Circuit protective devices. The intent is to ensure airplane
power generation and the related distribution systems are designed for
adequate capacity and safe operation under anticipated use and in the
event of a failure or malfunction.
viii. Proposed Sec. 23.1335, External and Cockpit Lighting
Proposed Sec. 23.1335 would require an applicant to design and
install all lights to prevent adverse effects on the performance of
flightcrew duties. Proposed Sec. 23.1335 would require position and
anti-collision lights, if installed, to have the intensities, flash
rate, colors, fields of coverage, and other characteristics to provide
sufficient time for another aircraft to avoid a collision. Proposed
Sec. 23.1335 would require position lights, if installed, to include a
red light on the left side of the airplane, a green light on the right
side of the airplane, spaced laterally as far apart as practicable, and
a white light facing aft, located on an aft portion of the airplane or
on the wing tips.
Proposed Sec. 23.1335 would require that an applicant design and
install any taxi and landing lights, if required by operational rules,
so they provide sufficient light for night operations. For seaplanes or
amphibian airplanes, this section would also require riding lights to
provide a white light visible in clear atmospheric conditions.
Airplanes moored or maneuvering on water are by mairtime law considered
watercraft; therefore, riding lights are required for seaplanes and
amphibians during water operations.
To encourage the installation of internal and external lighting
systems with new safety enhancing technology and streamline the
certification process, the FAA proposes removing most of the current
prescriptive requirements and the detailed means of compliance for
these requirements from current part 23.
[[Page 13493]]
The current prescriptive requirements would be replaced with
performance-based requirements. The FAA expects that current means of
compliance would continue to be used for the traditional airplane
designs under part 23.
Required lighting for the operation requested by an applicant would
have to be installed and approved as part of the type design. The
current rule requires that interior and exterior lighting function as
intended without causing any safety hazard in normal operation. The
proposed rule would require external lighting to make each airplane
visible at night at a distance allowing each pilot to maneuver in
sufficient time to avoid collision. The current rule specifies a
specific amount of light illumination accounting for airframe
obstructions. The FAA proposes removing this specified location and
amount of illumination because it is more appropriate as means of
compliance. The FAA does not consider small obstructions caused by
airplane structure to be a safety issue.
This section would capture the safety intent of current Sec. Sec.
23.1381, Instrument lights, paragraph (c); 23.1383, Taxi and landing
lights, paragraphs (a), (b) and (c); 23.1385, Position light system
installation, paragraphs (a), (b) and (c); 23.1387, Position light
dihedral angles; 23.1389, position light distribution and intensities;
23.1391, Minimum intensities in the horizontal plane of position
lights; 23.1393, Minimum intensities in any vertical plane of position
lights; 23.1395, Maximum intensities in overlapping beams of position
lights; 23.1397, color specifications; 23.1399, Riding light; and
23.1401, Anticollision light system, paragraphs (a), (a)(1), (b), (c),
(d), (e), and (f).
ix. Proposed Sec. 23.1400, Safety Equipment
Proposed Sec. 23.1400 would require safety and survival equipment,
required by the operating rules of this chapter, to be reliable,
readily accessible, easily identifiable, and clearly marked to identify
its method of operation.
The FAA proposes requirements for safety equipment needed for
emergency landings and ditching when required by operational rules, and
removal of the duplicative rules that are found in current part 23.
Required safety equipment would have to be installed, located, and
accessible for use in an emergency, and secured against emergency
landing accelerations. The proposed rule would require safety,
ditching, and survival equipment, be reachable, plainly marked for
operation, and not be damaged in survivable emergency landings.
This section would capture the safety intent of current Sec. Sec.
23.1411, Safety equipment--General, paragraphs (a) and (b)(1); and
23.1415; Ditching equipment, paragraphs (a), (c), and (d).
x. Proposed Sec. 23.1405, Flight in Icing Conditions
Proposed Sec. 23.1405 would require an applicant to demonstrate
its ice protection system would provide for safe operation, if
certification for flight in icing conditions is requested. Proposed
Sec. 23.1405 would also require these airplanes to be protected from
stalling when the autopilot is operating in a vertical mode. Proposed
Sec. 23.1405 would require this demonstration be conducted in
atmospheric icing conditions specified in part 1 of appendix C to part
25 of this chapter, and any additional icing conditions for which
certification is requested.
Proposed Sec. 23.1405 would capture the safety intent of current
Sec. 23.775(a) Windshields and windows, and Sec. 23.1419, Ice
protection. Proposed Sec. 23.1405 would also increase safety by adding
icing conditions beyond those specified in the current Sec. 23.1419.
The proposed Sec. 23.1405 would only apply to airplanes seeking
certification for flight in icing. The current Sec. 23.1419 only
applies to airplanes seeking certification for flight in icing;
however, ice protection systems can be certified without certification
for flight in icing.
The current ice protection system requirements in Sec. 23.1419(a)
would be captured in proposed Sec. 23.1405(a)(1). The proposed rule
would require an applicant to show systems are adequate in the icing
conditions for which certification is requested. As in the current
rule, ice protection systems would have to be shown to be adequate in
the icing conditions of appendix C to part 25. Freezing drizzle and
freezing rain icing conditions are optional icing conditions in which
the airplane may be certificated to operate. These icing conditions,
which the FAA added to appendix O to part 25 in amendment 25-140, are
not being defined in proposed Sec. 23.230. The FAA determined that the
definition of these optional icing conditions is more appropriate as a
means of compliance. Ice crystal conditions are added to this proposal
for certain air data probes to harmonize with EASA requirements.
The Part 23 Icing ARC recommendations on activation and operation
of ice protection systems would be used as a means of compliance to
proposed Sec. 23.1405(a)(1). This proposal would satisfy the intent of
NTSB Safety Recommendations A-07-14 and A-07-15.
Proposed Sec. 23.1405(a)(2) is the Part 23 Icing ARC
recommendation for airplanes certified under part 23 in icing and is
based on NTSB safety recommendation A-10-12. The target for this
proposed rule is older airplanes adding an autopilot for first time,
modifying certain autopilots on airplanes with a negative service
history in icing, or significant changes that affect performance or
flight characteristics. Proposed Sec. 23.1405 would require, under the
changed product rule, to add proposed Sec. 23.1405(a)(2) to the
certification basis without requiring the remainder of Sec. 23.1405
for certain autopilot modifications. For new airplanes, a stall warning
system that complies with proposed Sec. 23.230 would comply with
proposed Sec. 23.1405(a)(2). The vertical mode is a prescriptive
requirement to limit the applicability. Simple autopilots such as a
wing leveler would not be affected by this requirement. Numerous icing
accidents have shown that unrecognized airspeed loss can occur with
autopilots in altitude hold mode or vertical speed mode. Demonstration,
as a means of compliance, may include design and/or analysis and does
not mean natural icing flight tests are required.
xi. Proposed Sec. 23.1410, Pressurized System Elements
Proposed Sec. 23.1410 would require the minimum burst pressure
of--
Hydraulic systems be at least 2.5 times the design
operating pressure with the proof pressure at least 1.5 times the
maximum operating pressure;
Pressurization system elements be at least 2.0 times, and
proof pressure be at least 1.5 times, the maximum normal operating
pressure; and
Pneumatic system elements be at least 3.0 times, and proof
pressure be at least 1.5 times, the maximum normal operating pressure.
Additionally, this proposed section would also require that other
pressurized system elements have pressure margins that take into
account system design and operating conditions.
This section would capture the safety intent of current Sec. Sec.
23.1435, Hydraulic system, paragraphs (a)(4) and (b); 23.1437,
Accessories for multiengine airplanes; and 23.1438, Pressurization and
pneumatic systems, paragraphs (a) and (b).
xii. Proposed Sec. 23.1457, Cockpit Voice Recorders
The FAA is not proposing to revise current Sec. 23.1457 because
amendment
[[Page 13494]]
23-58 (73 FR 12542, March 7, 2008) and corrected on July 9, 2009 (74 FR
32799), was written to standardize the cockpit voice recorder rules to
address the NTSB's recommendations (70 FR 9752, February 28, 2005). The
FAA agrees with NTSB recommendation numbers A-96-89, A-96-171, A-99-18,
and parts of A-99-16 and A-99-17 and believes changing the current rule
to remove prescriptive requirements could hinder the conduct of future
accident investigations and be detrimental to aviation accident
investigations.
xiii. Proposed Sec. 23.1459, Flight Data Recorders
The FAA is not making any substantive changes to the current Sec.
23.1459 because amendment 23-58 (73 FR 12541, March 7, 2008) was
written to standardize the flight data recorder rules to address the
NTSB's recommendations. The FAA agrees with NTSB recommendation numbers
A-96-89, A-96-171, A-99-18, and parts of numbers A-99-16 and A-99-17
and believes changing the current rule to remove prescriptive
requirements could hinder the conduct of future accident investigations
and be detrimental to aviation safety. Proposed Sec. 23.1459(a)(1),
however, is amended to revise current references to Sec. Sec. 23.1323,
Airspeed indicating system; 23.1325, Static pressure system; and
23.1327, Magnetic direction indicator, as those sections are not
contained in this NPRM.
xiv. Current Subpart F Regulations Relocated to Other Proposed Subparts
The requirement currently in Sec. 23.1419(a) to comply with
subpart B requirements to show safe operating capability is moved to
proposed Sec. 23.230 as recommended by the Part 23 Icing ARC and Part
23 Reorganization ARC.
Ice protection of engine inlets would move to proposed Sec.
23.940, Powerplant ice protection. The Part 23 Reorganization ARC had
proposed that Sec. 23.1405 include these requirements, as well as
heated pitot probe requirements for IFR airplanes. The FAA decided to
separate them since compliance with proposed Sec. Sec. 23.940 and
23.1300 would be required for all airplanes, whereas compliance with
Sec. 23.1405 would be optional. The FAA wants to avoid potential
confusion on TCDS interpretation as to whether an airplane is certified
for flight in icing.
The requirements currently in Sec. 23.1381, Instrument lights,
paragraphs (a) and (b) would be relocated to proposed Sec. 23.1500,
Flightcrew Interface. The requirements currently in Sec. 23.1411,
Safety equipment--General, paragraph (b)(2) would be relocated to
proposed Sec. 23.600, Emergency conditions.
xv. Removal of Subpart F of the Current Regulations
When the FAA evaluated the current regulations, it determined that
the prescriptive icing requirements in Sec. Sec. 23.1323, Airspeed
indicating system, and 23.1325, Static pressure system, would be means
of compliance to proposed Sec. 23.1405(a)(1). The current requirement
for a heated pitot probe or an equivalent means on an IFR certified and
a flight in icing conditions airplane in current Sec. 23.1323(d) would
become a means of compliance for proposed Sec. 23.1300.
The part 23 re-write ARC had recommended that proposed Sec.
23.1405 include the requirement for a heated pitot probe on an IFR
certified airplane, but the FAA determined this would be better
addressed on a performance standard under proposed Sec. 23.1300,
because proposed Sec. 23.1405 would only apply to icing certified
airplanes. High altitude mixed phase and ice crystal conditions for
certain high-performance airplanes, and ice protection requirements for
stall warning and angle of attack would be means of compliance. The
proposed standard would harmonize with EASA requirements.
Current Sec. 23.1416 would be removed since the requirements for
proper inflation and annunciation of operation of pneumatic boots would
be covered on a performance basis in proposed Sec. Sec. 23.1300 and
23.1305. This would reflect that all types of ice protection systems
have annunciation requirements, and would eliminate unnecessary
annunciations. The Part 23 Icing ARC recommended this approach.
The analysis required in the current Sec. 23.1419(a), and all the
requirements in the current Sec. 23.1419(b) and (c), would become
means of compliance to proposed 1405(a) and would be removed.
Current Sec. 23.1419(d) requires a means to detect critical ice
accretions, including night lighting. The Part 23 Icing ARC had
proposed a new Sec. 23.1403 to replace these ice detection
requirements, which would also address the SLD detection required by
proposed Sec. 23.230. These ice detection requirements are more
appropriately addressed as a means of compliance to accommodate new
technology. For example, visual ice accretion detection as a means to
activate ice protection systems is no longer necessary on some designs,
examples being primary ice detection systems and icing conditions
detection systems. However, there would remain a requirement for pilots
to detect severe ice accretions, and this would be addressed in
proposed Sec. 23.230(b).
When the FAA evaluated the current regulations, it determined that
the prescriptive requirements in Sec. Sec. 23.1323, Airspeed
indicating system; 23.1325, Static pressure system; 23.1327, Magnetic
direction indicator; 23.1329, Automatic pilot system; 23.1335, Flight
director systems; 23.1337, Powerplant instruments installation;
23.1353, Storage battery design and installation; and 23.1357, Circuit
protective devices, would be covered on a performance basis by proposed
Sec. Sec. 23.1300; 23.1305; 23.1310; and 23.1315.
Current Sec. 23.1401, Anticollision light system, paragraph (a)(2)
would be removed as introductory material. Current Sec. 23.1415,
ditching equipment, paragraph (b) would be removed but could serve as a
means of compliance. The current Sec. Sec. 23.1435, Hydraulic systems,
paragraphs, (a), (a)(1), (a)(2), (a)(3), and (c); 23.1438,
Pressurization and pneumatic systems, paragraph (c), would be removed
as prescriptive design and means of compliance. Current Sec. 23.1443,
Minimum mass flow of supplemental oxygen, paragraph (d) would be
removed as a definition. Current Sec. 23.1445, paragraph (e) would be
removed as redundant to current Sec. 91.211, paragraph (a)(3).
7. Subpart G--Flightcrew Interface and Other Information
a. General Discussion
The FAA proposes to expand subpart G to address not only current
operating limitations and information, but also the concept of
flightcrew interface. Based on current technologies, the FAA
anticipates that new airplanes will heavily rely on automation and
systems that require new and novel pilot or flightcrew interface. The
FAA is proposing to address the pilot interface issues found in
subparts D and F with proposed Sec. 23.1500. Otherwise, subpart G
retains the safety requirements from the current rules without change.
Refer to appendix 1 of this preamble for a cross-reference table
detailing how the current regulations are addressed in the proposed
part 23 regulations.
b. Specific Discussion of Changes
i. Proposed Sec. 23.1500, Flightcrew Interface
Proposed Sec. 23.1500 would require the pilot compartment and its
equipment to allow the pilot(s) to perform their duties, including
taxi, takeoff, climb,
[[Page 13495]]
cruise, descent, approach, and landing; and perform any maneuvers
within the operating envelope of the airplane, without excessive
concentration, skill, alertness, or fatigue. Proposed Sec. 23.1500
would also require an applicant to install flight, navigation,
surveillance, and powerplant controls and displays so qualified
flightcrew could monitor and perform all tasks associated with the
intended functions of systems and equipment in order to make the
possibility that a flightcrew error could result in a catastrophic
event highly unlikely. Proposed Sec. 23.1500 would capture the safety
intent of current part 23 rules that are directly related to the pilot
or flightcrew interface with the airplane. Interfaces include controls,
displays, and visibility requirements.
Current and anticipated technologies that affect how the pilot
interfaces with the airplane are expected to expand faster than other
technologies. The FAA believes that significant safety improvements can
result from the evolution of how the pilot interfaces with the
airplane. Pilot workload is a major factor in causing accidents, but it
is almost impossible to connect workload-related mistakes to an
accident after the accident has happened. Evidence from large airplane
accidents, where we have recorded data as well as research, points to
the importance of the pilot interface and associated mistakes as causal
factors in aircraft accidents. The smart use of automation and phase-
of-flight-based displays could reduce pilot workload and increase pilot
awareness.
The converse is also true. Equipment is becoming available faster
than manufacturers and the FAA can evaluate it. Determining the safety
risks and recognizing the safety benefits of new technology available
to the pilot is important. For this reason, the proposed language
addresses the safety issues of the current Sec. Sec. 23.699, Wing flap
position indicator; 23.745 Nose/Tail wheel steering, 23.1303, Flight
and navigation instruments, paragraph (g)(3); 23.1321, Arrangement and
visibility, paragraphs (a),(b),(d), and (e); 23.1311, Electronic
display instrument systems, paragraphs (a)(6) and (7); 23.771, Pilot
compartment, paragraph (a), 23.773(a) Pilot compartment view, 23.777,
Cockpit controls; 23.779, Motion and effect of cockpit controls; and
23.781, Cockpit control knob shape; are addressed in proposed Sec.
23.1500(a) and (b). The proposed language would allow the FAA to
rapidly evaluate new equipment for concentration, skill, alertness, and
fatigue against pilot workload as is current practice. More
importantly, the FAA would remove the prescriptive requirements from
the current rules to allow for alternative approaches to pilot
interface that would reduce pilot workload or increase safety.
ii. Proposed Sec. 23.1505, Instrument Markings, Control Markings, and
Placards
Proposed Sec. 23.1505 would require each airplane to display in a
conspicuous manner any placard and instrument marking necessary for
operation. Proposed Sec. 23.1505 would also require an applicant to
clearly mark each cockpit control, other than primary flight controls,
as to its function and method of operation and include instrument
marking and placard information in the AFM. The consolidation of these
sections appears large, but many of these sections contain one
prescriptive requirement that, in many cases, is based on traditional
airplanes, instruments, and equipment.
iii. Proposed Sec. 23.1510, Airplane Flight Manual
Proposed Sec. 23.1510 would require an applicant to furnish an AFM
with each airplane that contains the operating limitations and
procedures, performance information, loading information, and any other
information necessary for the operation of the airplane.
The proposed rules capture the prescriptive list of information
that is considered necessary for the operation of the traditional
airplanes. The current rules contain very prescriptive and detailed
information. Furthermore, that level of detail assumes a traditional
airplane configuration and operation. The FAA proposes to remove this
detail from the rule because it is more appropriate as means of
compliance. Currently, the majority of airplanes certificated under
part 23 already use an industry standard to develop their AFMs--General
Aviation Manufactures Association Specification 1, Specification for
Pilot's Operating Handbook.\26\ The FAA already accepts this industry
standard for many airplanes certificated under part 23 because it
includes the information that is currently required in part 23. The FAA
believes that allowing alternative approaches to information would
facilitate new technology integration into airplanes certified under
part 23.
---------------------------------------------------------------------------
\26\ See www.regulations.gov (Docket #FAA-2015-1621).
---------------------------------------------------------------------------
The proposed Sec. 23.1510(d) would capture the safety intent of
the current Sec. Sec. 23.1505, Airspeed limitations, thru 23.1527,
Maximum operating altitude, specific to operating limitations and other
limitations and information necessary for safe operation.
iv. Proposed Sec. 23.1515, Instructions for Continued Airworthiness
Proposed Sec. 23.1515 would require an applicant to prepare
Instructions for Continued Airworthiness in accordance with proposed
appendix A to this part, that are acceptable to the Administrator,
prior to the delivery of the first airplane or issuance of a standard
certification of airworthiness, whichever occurs later. This proposed
section would capture the current Sec. 23.1529 without change. The FAA
proposes renaming Appendix G to Part 23--Instructions for Continued
Airworthiness, to Appendix A to Part 23--Instructions for Continued
Airworthiness.
8. Appendices to Part 23
a. General Discussion
Many of the appendices to part 23 contain information that the FAA
believes would be more appropriate as a means of compliance, with the
exception of Appendix G to Part 23-Instructions for Continued
Airworthiness. Appendices A, B, C, D, E, F, H, and J would be removed
and appendix G would be renamed Appendix A--Instructions for Continued
Airworthiness.
b. Specific Discussion of Changes
i. Proposed Appendix A to Part 23--Instructions for Continued
Airworthiness
The FAA proposes renaming Appendix G to Part 23--Instructions for
Continued Airworthiness, as Appendix A to Part 23--Instructions for
Continued Airworthiness.
ii. Removal of Appendices to Part 23
Appendix A to Part 23--Simplified Design Load Criteria. The FAA
proposes to remove this appendix because the content is more
appropriate for inclusion in methods of compliance.
Appendix B to Part 23--[Reserved]. The FAA proposes to remove this
appendix because it has been reserved since amendment 23-42. There is
no reason to include this appendix in the proposed revision to part 23.
Appendix C to Part 23--Basic Landing Conditions. The FAA proposes
to remove this appendix because the content is more appropriate for
inclusion in methods of compliance.
Appendix D to Part 23--Wheel Spin-Up and Spring-Back Loads. The FAA
proposes to remove this appendix because the content is more
appropriate for inclusion in methods of compliance.
Appendix E to Part 23--[Reserved]. The FAA proposes to remove this
[[Page 13496]]
appendix because the current appendix is reserved and contains no
information.
Appendix F to Part 23--Test Procedure. The FAA proposes to remove
this appendix because this is purely a means of showing compliance for
materials that must comply with self-extinguishing flammability
requirements.
Appendix H to Part 23--Installation of an Automatic Power Reserve
(APR) System. The FAA proposes to remove this appendix because the FAA
believes that the detailed and prescriptive language of appendix H is
more appropriate as means of compliance.
Appendix I to Part 23--Seaplane Loads. The FAA proposes to remove
this appendix because the content is more appropriate for inclusion in
methods of compliance.
Appendix J to Part 23--HIRF Environments and Equipment HIRF Test
Levels. The accepted HIRF environment is codified as appendix J to part
23--HIRF Environments and Equipment HIRF Test Levels. The proposed
language in Sec. 23.1325 would revise this to the expected HIRF
environment. The current appendix J to part 23 would remain an accepted
expected HIRF environment until the Administrator accepted other
levels. Any new expected HIRF environment would be found in FAA
guidance material or other standards accepted by the Administrator.
This would allow the certification requirement to match the current
threat agreed to over time. Additionally, the proposed language would
clarify that the failure consequence of interest is at the airplane
level, which allows credit for design and installation architecture.
B. Miscellaneous Amendments (Sec. Sec. 21.9, 21.17, 21.24, 21.35,
21.50, 21.101, 35.1, 35.37, 91.205, 91.313, 91.323, 91.531, 121.310,
135.169, and Appendix E to Part 43)
1. Production of Replacement and Modification Articles (Sec. 21.9)
The FAA proposes amending Sec. 21.9 by adding paragraph (a)(7) to
provide applicants with an alternative method to obtain FAA approval to
produce replacement and modification articles that are reasonably
likely to be installed on type certificated aircraft. We also propose
to revise paragraphs (b) and (c) to specify these articles would be
suitable for use in a type certificated product. These proposed changes
would allow an applicant to submit production information for a
specific article, but would not require the producer of the article to
apply for approval of the article's design or obtain approval of its
quality system. Accordingly, approval to produce a modification or
replacement article under proposed Sec. 21.9(a)(7) would not
constitute a production approval as defined in Sec. 21.1(b)(6). The
FAA intends to limit use of this procedure to articles whose improper
operation or failure would not cause a hazard. Approval would be
granted to the applicant on a case-by-case basis, specific to the
installation proposed, accounting for potential risk and considering
the safety continuum.
2. Designation of Applicable Regulations (Sec. 21.17)
The FAA proposes amending Sec. 21.17, by removing the reference to
Sec. 23.2, because this section would be deleted. The requirements in
Sec. 23.2 are currently addressed in the operational rules. Since
Sec. 23.2 is a retroactive rule, it is appropriate for the requirement
to be in the operating rules. As a result, the FAA also proposes
amending Sec. 91.205 by revising paragraphs (b)(13) and (b)(14) to
ensure removing this requirement would not have any effect on the
existing fleet.
3. Issuance of Type Certificate: Primary Category Aircraft (Sec.
21.24)
The FAA proposes amending Sec. 21.24 by revising paragraph
(a)(1)(i) to modify the phrase as defined by Sec. 23.49 to include
reference to amendment 23-62 (76 FR 75736, December 2,2011), effective
on January 31, 2012. This revision is necessary to maintain a complete
definition of stall speed in this section, as the current Sec. 23.49
would be removed from the proposed rule.
4. Flight Tests (Sec. 21.35)
The FAA proposes amending Sec. 21.35 by revising paragraph (b)(2)
to delete the reference to reciprocating engines and expanding the
exempted airplanes to include all low-speed part 23 airplanes 6,000
pounds or less. This proposed change would align the requirements for
function and reliability testing with the proposed changes in part 23
that do not distinguish between propulsion types. This change would
allow the FAA flexibility to address new propulsion types based on the
changes to part 23.
5. Instructions for Continued Airworthiness and Manufacturer's
Maintenance Manuals Having Airworthiness Limitations Sections (Sec.
21.50)
The FAA proposes amending Sec. 21.50(b) to reference Sec. 23.1515
rather than Sec. 23.1529. This change is editorial and would align
with the proposed part 23 numbering convention.
6. Designation of Applicable Regulations (Sec. 21.101)
The FAA proposes amending Sec. 21.101 by removing the reference to
Sec. 23.2 as this section is proposed to be deleted and is addressed
in the operating rules, and to refer to the proposed part 23
certification levels in paragraph (c). The current 6,000-pound
reference would be augmented by the inclusion of simple airplanes,
certification level 1 low-speed airplanes, and certification level 2
low-speed airplanes, in order to align the current rules with the
proposed part 23 certification levels.
Additionally, the FAA recognizes that it may be impractical for
airplanes certified under part 23, amendment 23-62, or prior
amendments, to move up to the latest amendment for modifications.
Section 21.101 would not be revised to address this circumstance, as
this section allows for certification at a lower amendment level if
meeting the current amendment is impractical. This current provision
would allow for compliance to the certification requirements at
amendment 23-62 or earlier when compliance to the latest amendment of
part 23 was determined by the FAA to be impractical.
7. Applicability (Sec. 35.1)
The FAA proposes amending Sec. 35.1 by replacing the reference to
Sec. 23.907 with proposed Sec. 23.905(c).
8. Fatigue Limits and Evaluation (Sec. 35.37)
The FAA proposes amending Sec. 35.37 by replacing the reference to
Sec. 23.907 with proposed Sec. 23.905(c).
9. Altimeter System Test and Inspection (Appendix E to Part 43)
The FAA proposes amending appendix E to part 43 by revising
paragraph (a)(2) to conform with proposed part 23 changes. This
proposed change would affect owners and operators of part 23
certificated airplanes in controlled airspace under instrument flight
rules who must comply with Sec. 91.411. Concurrent with this rule
change, AC 43-6, Altitude Reporting Equipment and Transponder System
Maintenance and Inspection Practices, would be revised to include a
static pressure system proof test acceptable to the Administrator.
Additionally, while reviewing appendix E to part 43, paragraph (a)(2),
we noted that it remains silent on parts 27 and 29 rotorcraft and Civil
Air Regulations certificated aircraft. The static pressure system proof
test in AC 43-6 ensures the accuracy needed to meet Sec. 91.411
requirements.
[[Page 13497]]
10. Powered Civil Aircraft With Standard Category U.S. Airworthiness
Certificates: Instrument and Equipment Requirements (Sec. 91.205)
The FAA proposes amending Sec. 91.205 by revising paragraphs
(b)(13) and (b)(14) to include the potential for allowing other
approved restraint systems. Additionally, paragraph (b)(14) refers to
Sec. 23.561(b)(2), which would be retitled in the proposed revision
for structural strength limits and would be addressed in the means of
compliance. Section 91.205(b)(16) would be deleted and incorporated
into (b)(14) with no additional requirements. The part 23 proposal
would delete references to utility and acrobatic categories, as they
would be incorporated into the normal categories that would be
redefined into performance-based standards.
11. Restricted Category Civil Aircraft: Operating Limitations (Sec.
91.313)
The FAA proposes amending Sec. 91.313(g) to include the potential
for allowing other approved restraint systems. Additionally, paragraph
(g) includes a regulatory reference to Sec. 23.561(b)(2), which would
be retitled in the proposed revision as Sec. 23.600, which would be
accompanied by accepted means of compliance. Approval for a shoulder
harness or restraint system, therefore, would require withstanding the
static inertia loads specified in Sec. 23.600 during emergency
conditions.
12. Increased Maximum Certification Weights for Certain Airplanes
Operated in Alaska (Sec. 91.323)
The FAA proposes amending Sec. 91.323 by removing reference to
Sec. 23.337 because this section would be revised and consolidated
with other structural requirements. The relevant prescriptive
requirement(s) maneuvering load factors found in Sec. 23.337 would be
added to the regulation in Sec. 91.323(b)(3).
13. Second in Command Requirements (Sec. 91.531)
The FAA proposes amending Sec. 91.531(1) and (3) to incorporate
the new risk and performance levels proposed in this NPRM. The FAA
proposes deleting the reference to utility, acrobatic, and commuter
categories in part 23. Other divisions would be used to define levels
of certification for normal category airplanes. This proposed amendment
would ensure airplanes certificated in the commuter category in the
past and airplanes certificated in the future under the proposed part
23 airworthiness and performance levels would be addressed in this
rule.
14. Additional Emergency Equipment (Sec. 121.310)
The FAA proposes amending Sec. 121.310(b)(2)(iii) to reflect the
reference to Sec. 23.811(b), effective June 16, 1994. This would be an
update to the reference for conformity only. This amendment would make
no change to the requirements of the rule.
15. Additional Airworthiness Requirements (Sec. 135.169)
The FAA proposes amending Sec. 135.169(b) by deleting the terms,
``reciprocating-engine or turbopropeller-powered''. The current rule
limits operation under this part to reciprocating-engine or
turbopropeller-powered small airplanes. By amending the paragraph as
proposed, other small airplanes, regardless of propulsion type and
including turbojet-powered, would potentially be considered for
certification under this part.
The FAA also proposes to allow a small airplane in normal category,
in Sec. 135.169(b)(8), to operate within the rules governing commuter
and on demand operations. This action would be necessary as a result of
the proposed part 23 rules which would sunset the commuter category for
newly type certificated airplanes and create a normal category,
certification level 4 airplane as equivalent to the commuter category
by applying to 10-19 passengers. This proposed amendment would allow
for the consideration of the new category airplane and to ensure a
continued higher level of safety for commercial operations. Because of
the ground-breaking nature of the part 23 proposals, the associated
adjustment to performance-based airworthiness standards in future
airplane designs and manufacturing, and the myriad of potential
possibilities for attaining a means of compliance for airplane type
certification, the FAA proposes to require the new normal category
certification level 4 airplanes to meet the current airworthiness and
performance standards of the commuter category found in part 23 thru
amendment 23-62. These standards are envisioned to remain as
requirements for the new normal category certification level 4
airplanes into the near-term future, but not the long-term. It is
intended that once the new part 23 requirements have proven successful
with the new normal category certification levels 1, 2, and 3
airplanes, the FAA would reconsider normal category certification level
4 airplanes for part 135 commercial operations.
VII. Regulatory Notices and Analyses
A. Regulatory Evaluation Summary
Changes to Federal regulations must undergo several economic
analyses. First, Executive Order 12866 and Executive Order 13563 direct
that each Federal agency shall propose or adopt a regulation only upon
a reasoned determination that the benefits of the intended regulation
justify its costs. Second, the Regulatory Flexibility Act of 1980 (Pub.
L. 96-354) requires agencies to analyze the economic impact of
regulatory changes on small entities. Third, the Trade Agreements Act
(Pub. L. 96-39) prohibits agencies from setting standards that create
unnecessary obstacles to the foreign commerce of the United States. In
developing U.S. standards, this Trade Act requires agencies to consider
international standards and, where appropriate, that they be the basis
of U.S. standards. Fourth, the Unfunded Mandates Reform Act of 1995
(Pub. L. 104-4) requires agencies to prepare a written assessment of
the costs, benefits, and other effects of proposed or final rules that
include a Federal mandate likely to result in the expenditure by State,
local, or tribal governments, in the aggregate, or by the private
sector, of $100 million or more annually (adjusted for inflation with
base year of 1995). This portion of the preamble summarizes the FAA's
analysis of the economic impacts of this proposed rule. We suggest
readers seeking greater detail read the full regulatory evaluation, a
copy of which we have placed in the docket for this rulemaking.
In conducting these analyses, FAA has determined that this proposed
rule: (1) Would have benefits that justify its costs, (2) would not be
an an economically ``significant regulatory action'' as defined in
section 3(f) of Executive Order 12866, (3) would be ``significant'' as
defined in DOT's Regulatory Policies and Procedures; (4) would have a
significant positive economic impact on small entities; (5) would not
create unnecessary obstacles to the foreign commerce of the United
States; and (6) would not impose an unfunded mandate on state, local,
or tribal governments, or on the private sector by exceeding the
threshold identified above. These analyses are summarized below.
1. Total Benefits and Costs of This Rule
The following table shows the estimated benefits and costs of the
proposed rule. The major factors driving the expected costs of this
proposal are the additional training tasks, database development, and
documentation to
[[Page 13498]]
FAA and industry part 23 certification engineers. Benefits consist of
safety benefits from preventing stall and spin accidents and savings
from reducing the number of special conditions, exemptions, and
equivalent levels of safety. If the proposed rule saves only one human
life by improving stall characteristics and stall warnings, that alone
would result in benefits outweighing the costs.
Estimated Benefits and Costs From 2017 to 2036
[2014 $ Millions]
------------------------------------------------------------------------
Safety benefits + cost
Costs savings = total
benefits
------------------------------------------------------------------------
Total.......................... $3.9 $19.6 + $12.6 = $32.2.
Present value.................. $3.9 $6.2 + $5.8 = $12.0.
------------------------------------------------------------------------
2. Who is potentially affected by this rule?
The proposal would affect U.S. manufacturers and operators of new
part 23 type certificated airplanes.
3. Assumptions
The benefit and cost analysis for the regulatory evaluation is
based on the following factors/assumptions:
The analysis is conducted in constant dollars with 2014
as the base year.
The final rule would be effective in 2017.
The primary analysis period for costs and benefits
extends for 20 years, from 2017 through 2036. This period was
selected because annual costs and benefits will have reached a
steady state by 2036.
Future part 23 type certifications and deliveries are
estimated from historical part 23 type certifications and
deliveries.
Costs for the new part 23 type certifications
forecasted in the ``Fleet Discussion'' section of the regulatory
evaluation would occur in year 1 of the analysis interval.
Airplane deliveries from the forecasted part 23 type
certificates would start in year 5 of the analysis interval.
The FAA uses a seven percent discount rate for the
benefits and costs as prescribed by OMB in Circular A-4.
The baseline for estimating the costs and benefits of
the proposed rule would be part 23, through amendment 62.
The FAA estimates 335 FAA part 23 certification
engineers would require additional training as a result of this
proposal. The FAA assumes that the same number of industry part 23
certification engineers would also require additional training as a
result of this proposal.
The FAA estimates that this proposal would add 16 hours
of training to FAA and industry part 23 certification engineers.
Since this training program would be on-line, we
estimate no travel costs for the engineers.
FAA pay-band tables and the Bureau of Labor Statistics
(BLS) determine the hourly wages used to estimate the costs to the
FAA and applicants.
Using the U.S. Department of Transportation guidance,
the wage multiplier for employee benefits is 1.17.\27\
---------------------------------------------------------------------------
\27\ On January 30, 2014, the DOT published a memo on
``Estimating Total Costs of Compensation Based on Wage Rates or
Salaries.'' The memo directs the FAA that when a rule requires
incremental hours per existing employee, the wage/salary multiplier
is of smaller magnitude because not all categories of employer
provided benefits increase with additional hours worked by an
individual employee.
---------------------------------------------------------------------------
4. Benefits of This Rule
The major safety benefit of this proposed rule is to add stall
characteristics and stall warnings that would result in airplane
designs that are more resistant to depart controlled flight
inadvertently. The largest number of accidents for small airplanes is a
stall or departure-based LOC in flight. This proposal would also have
cost savings by streamlining the certification process and encouraging
new and innovative technology. Streamlining the certification process
would reduce the issuance of special conditions, exemptions, and
equivalent level of safety findings.
5. Costs of This Rule
The proposed rules major costs are the engineer training costs and
the certification database creation costs. Additional costs would also
accrue from the proposed controllability and stall sections that would
increase scope over current requirements and manual upgrade costs.
In the following table, we summarize the total estimated compliance
costs by category. The FAA notes that since we assumed that all costs
occurred in Year 1 of the analysis interval, the 2014-dollar costs
equal the present value costs.
Total Cost Summary by Category
------------------------------------------------------------------------
Total costs
Type of cost (2014$) and
P.V.
------------------------------------------------------------------------
Sec. 23.200 Controllability........................... $276,939
Sec. 23.215 Stall characteristics, stall warning, and 500,000
spins..................................................
Engineer Training Costs................................. 1,149,418
Certification Database Costs............................ 1,293,750
Manual Upgrade Costs.................................... 700,000
---------------
Total Costs......................................... 3,920,106
------------------------------------------------------------------------
* These numbers are subject to rounding error.
B. Initial Regulatory Flexibility Determination
The Regulatory Flexibility Act of 1980 (Pub. L. 96-354) (RFA)
establishes ``as a principle of regulatory issuance that agencies shall
endeavor, consistent with the objectives of the rule and of applicable
statutes, to fit regulatory and informational requirements to the scale
of the businesses, organizations, and governmental jurisdictions
subject to regulation. To achieve this principle, agencies are required
to solicit and consider flexible regulatory proposals and to explain
the rationale for their actions to assure that such proposals are given
serious consideration.'' The RFA covers a wide-range of small entities,
including small businesses, not-for-profit organizations, and small
governmental jurisdictions.
Agencies must perform a review to determine whether a rule will
have a significant economic impact on a substantial number of small
entities. If the agency determines that it will, the agency must
prepare a regulatory flexibility analysis as described in the RFA.
The FAA believes that this proposed rule could have a significant
economic impact on a substantial number of entities because we believe
that this rule could enable the creation of new part 23 type
certificates and new manufacturers. The FAA has been working with U.S.
and foreign small aircraft manufacturers since 2007 to review the life
cycle of part 23 airplanes and determine what needed improvement.
The purpose of this analysis is to provide the reasoning underlying
the FAA determination.
[[Page 13499]]
Under Section 603(b) of the RFA, the initial analysis must address:
Description of reasons the agency is considering the
action;
Statement of the legal basis and objectives for the
proposed rule;
Description of the record keeping and other compliance
requirements of the proposed rule;
All federal rules that may duplicate, overlap, or
conflict with the proposed rule;
Description and an estimated number of small entities
to which the proposed rule will apply; and
Describe alternatives considered.
1. Reasons Why the Rule Is Being Proposed
The FAA proposes this action to amend the airworthiness standards
for new part 23 type certificated airplanes to reflect the current
needs of the small airplane industry, accommodate future trends,
address emerging technologies, and enable the creation of new part 23
manufacturers and new type certificated airplanes. The proposed changes
to part 23 are necessary to eliminate the current workload of
exemptions, special conditions, and equivalent levels of safety
findings necessary to certificate new part 23 airplanes. These proposed
part 23 changes would also promote safety by enacting new regulations
for controllability and stall standards and promote new technologies in
part 23 airplanes.
2. Statement of the Legal Basis and Objectives
The FAMRA required the Administrator, in consultation with the
aviation industry, to assess the aircraft certification and approval
process. In addition, the SARA directs the FAA to create performance-
based regulations for small airplanes and provide for the use of
industry developed consensus standards to allow flexibility in the
certification of new technology.
Accordingly, this proposed rule would amend Title 14 of the Code of
Federal Regulations to revise the airworthiness standards for small
airplanes by removing current prescriptive design requirements and
replacing those requirements with risk and performance-based
airworthiness standards.
The FAA's authority to issue rules on aviation safety is found in
Title 49 of the United States Code. Subtitle I, Section 106 describes
the authority of the FAA Administrator. Subtitle VII, Aviation
Programs, describes in more detail the scope of the agency's authority.
This rulemaking is promulgated under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701. Under that section,
the FAA is charged with promoting safe flight of civil airplanes in air
commerce by prescribing minimum standards required in the interest of
safety for the design and performance of airplanes. This regulation is
within the scope of that authority because it prescribes new
performance-based safety standards for the design of normal category
airplanes.
3. Projected Reporting, Recordkeeping and Other Requirements
The FAA expects no more than minimal new reporting and
recordkeeping compliant requirements would result from this proposed
rule because the prescriptive nature of part 23 would be in other FAA
approved documents where future technology can readily be adopted into
the regulatory framework. The FAA requests comment regarding the
anticipated reduction in paperwork and recordkeeping burdens that may
result from this revision.
4. Overlapping, Duplicative, or Conflicting Federal Rules
The proposed rule would not overlap, duplicate, or conflict with
existing federal rules.
5. Estimated Number of Small Firms Potentially Impacted
Under the RFA, the FAA must determine whether a proposed or final
rule significantly affects a substantial number of small entities. This
determination is typically based on small entity size and cost
thresholds that vary depending on the affected industry. Using the size
standards from the Small Business Administration for Air Transportation
and Aircraft Manufacturing, we defined companies as small entities if
they have fewer than 1,500 employees.\28\
---------------------------------------------------------------------------
\28\ 13 CFR 121.201, Size Standards Used to Define Small
Business Concerns, Sector 48-49 Transportation, Subsector 481 Air
Transportation.
---------------------------------------------------------------------------
There are seven U.S. owned aircraft manufacturers who delivered
part 23 airplanes in the 1998-2013 analysis interval. These
manufacturers are Adam, American Champion, Cessna, Hawker Beechcraft,
Maule, Quest, and Sino-Swearingen.
Using information provided by the Internet filings and news
reports, manufacturers that are subsidiary businesses of larger
businesses, manufacturers that are foreign owned, and businesses with
more than 1,500 employees were eliminated from the list of small
entities. Cessna and Hawker Beechcraft are businesses with more than
1,500 employees. For the remaining businesses, we obtained company
revenue and employment from the above sources.
The base year for the final rule is 2014. Although the FAA
forecasts traffic and air carrier fleets, we cannot determine either
the number of new entrants or who will be in the part 23 airplane
manufacturing business in the future. Therefore, we use current U.S.
part 23 airplane manufacturers' revenue and employment in order to
determine the number of small entities this proposed rule would affect.
The methodology discussed above resulted in the following list of
five U.S. part 23 airplane manufacturers, with less than 1,500
employees.
------------------------------------------------------------------------
Number of
Manufacturer employees Annual revenue
------------------------------------------------------------------------
Part 23 Manufacturer 1.................. 2 $110,000
Part 23 Manufacturer 2.................. 65 7,000,000
Part 23 Manufacturer 3.................. 75 35,000,000
Part 23 Manufacturer 4.................. 175 34,000,000
Part 23 Manufacturer 5.................. 2 97,000
------------------------------------------------------------------------
From this list of small entity U.S. airplane manufacturers, there
are three manufacturers currently producing part 23 reciprocating
engine airplanes; only one manufacturer producing turboprops and only
one producing turbojets. The single manufacturer producing a part 23
turbojet has not delivered an airplane since 2009 and is still working
on
[[Page 13500]]
acquiring the means to start up its production line again. One of the
manufacturers producing a part 23 reciprocating engine airplane has not
delivered an airplane since 2007 and is working on acquiring the means
to start up their production line again. The FAA is not aware that
either of these manufacturers is considering a new airplane for part 23
type certification in the future and therefore this proposed rulemaking
would most likely not add costs to these two manufacturers because the
proposed rule only affects new part 23 type certificates.
For the remaining two reciprocating engine part 23 airplane
manufacturers, their last type certificates were issued in 1961 and
1970. The 1961 type certificate was issued for the only airplane this
manufacturer produces and the manufacturer with the 1970 type
certificate produces one other airplane that was type certificated in
1941. The last small entity manufacturer produces only turboprop
airplanes and it started delivering airplanes in 2007. Again, the FAA
is not aware that any of these manufacturers is considering a new
airplane for part 23 type certification in the future and therefore
this proposed rulemaking would most likely not add costs for it.
While this rulemaking may enable the creation of new manufacturers,
the FAA is not aware of any new small entity part 23 manufacturers who
want a type certification in the future for a new part 23 airplane.
However, by simplifying and lowering the costs for certification of new
small airplanes, barriers to entry may be lowered and thus new
manufacturers may emerge.
6. Cost and Affordability for Small Entities
In 2009, a joint FAA/industry team finalized the Part 23 CPS. This
proposed rulemaking resulted from this study by the recommendation to
use consensus standards to supplement the regulatory language. Since
then, the FAA and the part 23 industry have worked together to develop
common part 23 airplane certification requirements for this rulemaking.
In 2011, with the Part 23 CPS as a foundation, the FAA formed the Part
23 Reorganization ARC. The ARC consisted of large and small entity
domestic and international businesses. We contacted the part 23
airplane manufacturers, the ARC, and GAMA for specific cost estimates
for each section change for the rule and they all believe that this
proposed rule would have a minimal cost impact on their operations and
in many cases, would have significant cost savings by streamlining the
part 23 type certification process. Many of the ARC members
collaborated and provided a joint cost estimate for the proposed rule.
The ARC has informed us that the proposed rule would save the
manufacturers design time for the certification of part 23 airplanes by
reducing the number of exemptions, equivalent level of safety findings
and special conditions required to incorporate new and future
technology into their new airplane certifications. The proposed rule
would also require manuals to be updated and database development. We
expect these updates to be minimal and request commen on these
anticipated costs and overall reduction in paperwork burden.
The ARC has also informed us that every other section of this
proposed rule would be cost-neutral since the majority of the
prescriptive requirements in part 23 would be moved from part 23. The
FAA expects that these current requirements would form the basis for
consensus standards that would be used as a means of compliance to the
proposed performance based regulations.
The FAA expects this proposed rule could have a positive economic
impact to small entities because it would enable new businesses to
produce new part 23 type certificated airplanes while maintaining a
safe operating environment in the NAS. This proposal is based on the
ARC's recommendations and would allow for the use of consensus
standards that have been developed in partnership with industry.
Therefore, the FAA believes that this proposed rule could have a
positive significant economic impact on a substantial number of
entities.
7. Alternative Analysis
a. Alternative 1
The FAA would continue to issue special conditions, exemptions, and
equivalent level of safety findings to certificate part 23 airplanes.
As this approach would not follow congressional direction, we choose
not to continue with the status quo.
b. Alternative 2
The FAA would continue to enforce the current regulations that
affect stall and controllability. The FAA rejected this alternative
because the accident rate for part 23 airplanes identified a safety
issue that had to be addressed.
c. Alternative 3
The FAA notes that a multi-engine part 23 aircraft manufacturer
could decide it wants to comply with Sec. 23.200(b) by making the
airplane capable of climbing after a critical loss by installing larger
engines. But this is a very expensive alternative that would raise
certification costs and operating costs and we believe that part 23
aircraft manufacturers would not make the airplane capable of climbing
after a critical loss by installing larger engines.
The FAA solicits comments regarding this determination.
C. International Trade Impact Assessment
The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal
agencies from establishing standards or engaging in related activities
that create unnecessary obstacles to the foreign commerce of the United
States. Pursuant to these Acts, the establishment of standards is not
considered an unnecessary obstacle to the foreign commerce of the
United States, so long as the standard has a legitimate domestic
objective, such as the protection of safety, and does not operate in a
manner that excludes imports that meet this objective. The statute also
requires consideration of international standards and, where
appropriate, that they be the basis for U.S. standards. The FAA has
assessed the potential effect of this proposed rule and determined that
the standards are necessary for aviation safety and would not create
unnecessary obstacles to the foreign commerce of the United States.
D. Unfunded Mandates Assessment
Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement
assessing the effects of any Federal mandate in a proposed or final
agency rule that may result in an expenditure of $100 million or more
(in 1995 dollars) in any one year by State, local, and tribal
governments, in the aggregate, or by the private sector; such a mandate
is deemed to be a ``significant regulatory action.'' The FAA currently
uses an inflation-adjusted value of $155.0 million in lieu of $100
million. This proposed rule does not contain such a mandate; therefore,
the requirements of Title II of the Act do not apply.
E. Paperwork Reduction Act
The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires
that the FAA consider the impact of paperwork and other information
collection burdens imposed on the public. The information requirements
for aircraft certification are covered by existing OMB No. 2120-0018.
Burdens associated with special conditions,
[[Page 13501]]
ELOS, and exemptions are not quantified in this collection because the
need to seek relief under one of these options is dependent on each
applicant and is difficult to quantify. It is expected that this
rulemaking would reduce the number of special conditions, ELOS, and
exemptions filed, thus reducing paperwork and processing time for both
the FAA and industry. It would also maintain the fundamental safety
requirements from the current part 23 regulations but allow more
flexibility in airplane designs, faster adoption of safety enhancing
technology, and reduce the regulatory cost burden. To estimate savings
driven by this change, the FAA counted the special conditions, ELOS,
and exemption applications submitted to the FAA for part 23 aircraft
between 2012 and 2013 and divided the number by two years for an
average of 47 applications per year.\29\ The ARC report offered a
similar average of 37 applications per year.\30\ Additionally, the FAA
counted the number of pages per application for all 47 applications to
obtain an average number of pages per application. For special
conditions, there were approximately 21 pages, 16 pages for an
exemption, and 15 pages per ELOS application. The FAA assumes that the
applicant and each FAA office that reviews the application spend 8
hours on research, coordination, and review per page. The ARC also
noted ``an ELOS finding or exemption can take the FAA between 4 to 12
months to develop and approve. The applicant spends roughly the same
amount of time as the FAA in proposing what they need and responding to
FAA questions for SC, exemption, or ELOS.'' \31\
---------------------------------------------------------------------------
\29\ https://my.faa.gov/org/linebusiness/avs/offices/air/tools/cert.html.
\30\ A report from the 14 CFR part 23 Reorganization Aviation
Rulemaking Committee to the Federal Aviation Administration;
Recommendation for increasing the safety of small general aviation
airplanes certificated to 14 CFR part 23, June 5, 2013, Table 7.1--
Special Conditions, Exemptions, Equivalent Safety Findings, Page 55.
\31\ Ibid., 54.
---------------------------------------------------------------------------
The number of applications is multiplied by the number of pages and
by the hourly wage for the applicant and different FAA offices to
account for the cost to the FAA and the applicant. The estimated hourly
wage is $74.10 for a Small Airplane Directorate employee,\32\ $50.75
for an Aircraft Certificate Office employee,\33\ and $60.58 for an
engineer \34\ employed by the applicant. Annual cost equals the sum of
the associated costs of special conditions, exemptions, plus equivalent
level of safety. Yearly cost totals roughly $502,469 for the Small
Airplane Directorate, $344,172 for Aircraft Certificate Offices, and
$410,823 for the applicants. Tables 1, 2, and 3 show cost by office and
applicant as well as by special condition, exemption, and ELOS.
---------------------------------------------------------------------------
\32\ 2014 FAA Bay Band, Average K Band Salary (Rest of the U.S.)
plus wage multiplier for benefits https://employees.faa.gov/org/staffoffices/ahr/program_policies/policy_guidance/hr_policies/hrpm/comp/comp_ref/2014payadjustment/.
\33\ 2014 FAA Bay Band, Average I Band Salary (Rest of the U.S.)
plus wage multiplier for benefits https://employees.faa.gov/org/staffoffices/ahr/program_policies/policy_guidance/hr_policies/hrpm/comp/comp_ref/2014payadjustment/.
\34\ National Occupational Employment and Wage Estimates United
States, May 2014; Aerospace Engineer mean hourly wage, NAIC code 17-
2011 plus wage multiplier for benefits http://www.bls.gov/oes/current/oes_nat.htm#17-0000. A more detailed discussion is provided
in the ``Costs'' section below.
Table 1--Savings From Special Conditions (SC) *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average number Average FAA SAD FAA ACO Applicant
Part 23 Section of SC (2012- number of -----------------------------------------------------------------------------
2013) pages Man-hours Savings Man-hours Savings Man-hours Savings
--------------------------------------------------------------------------------------------------------------------------------------------------------
143.......................................... 0.5 20.8 83 $6,165 83 $4,223 83 $5,040
171.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
173.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
175.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
177.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
251.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
361.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
562.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
572.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
573.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
574.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
613.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
627.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
629.......................................... 1.5 20.8 250 18,495 250 12,668 250 15,121
901.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
939.......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
951.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
961.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
973.......................................... 1 20.8 166 12,330 166 8,445 166 10,081
977.......................................... 1.5 20.8 250 18,495 250 12,668 250 15,121
1141......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
1301......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
1305......................................... 1 20.8 166 12,330 166 8,445 166 10,081
1308......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
1309......................................... 1 20.8 166 12,330 166 8,445 166 10,081
1329......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
1337......................................... 0.5 20.8 83 6,165 83 4,223 83 5,040
1521......................................... 1 20.8 166 12,330 166 8,445 166 10,081
1557......................................... 1 20.8 166 12,330 166 8,445 166 10,081
3Pt Restraint with Airbag.................... 0.5 20.8 83 6,165 83 4,223 83 5,040
Inflatable Restraint......................... 0.5 20.8 83 6,165 83 4,223 83 5,040
Electronic Engine Controls................... 0.5 20.8 83 6,165 83 4,223 83 5,040
[[Page 13502]]
Fuel Jettisoning............................. 0.5 20.8 83 6,165 83 4,223 83 5,040
Load Alleviation System...................... 0.5 20.8 83 6,165 83 4,223 83 5,040
Side Facing Seat with Airbag................. 0.5 20.8 83 6,165 83 4,223 83 5,040
----------------------------------------------------------------------------------------------------------
Totals................................... 24.5 728 4077 302,080 4077 206,914 4077 246,983
--------------------------------------------------------------------------------------------------------------------------------------------------------
* These numbers are subject to rounding error.
Table 2--Savings From Exemptions *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average number Average FAA SAD FAA ACO Applicant
Part 23 Section exemptions number of -----------------------------------------------------------------------------
(2012-2013) pages Man-hours Savings Man-hours Savings Man-hours Savings
--------------------------------------------------------------------------------------------------------------------------------------------------------
1359......................................... 0.5 15.6 62.4 $4,624 62 $3,167 62 $3,780
1549......................................... 0.5 15.6 62.4 4,624 62 3,167 62 3,780
177.......................................... 0.5 15.6 62.4 4,624 62 3,167 62 3,780
49........................................... 1 15.6 124.8 9,247 125 6,334 125 7,561
562.......................................... 1 15.6 124.8 9,247 125 6,334 125 7,561
1419......................................... 0.5 15.6 62.4 4,624 62 3,167 62 3,780
----------------------------------------------------------------------------------------------------------
Totals................................... 4 94 499 36,989 499 25,336 499 30,243
--------------------------------------------------------------------------------------------------------------------------------------------------------
* These numbers are subject to rounding error.
Table 3--Savings From Equivalent Level of Safety (ELOS) *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average number Average FAA SAD FAA ACO Applicant
Part 23 Section ELOS (2012- number of -----------------------------------------------------------------------------
2013) pages Man-hours Savings Man-hours Savings Savings Man-hours
--------------------------------------------------------------------------------------------------------------------------------------------------------
145.......................................... 1 14.9 119.2 $8,832 119 $6,050 119 $7,221
207.......................................... 1 14.9 119.2 8,832 119 6,050 119 7,221
672.......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
777.......................................... 1.5 14.9 178.8 13,249 179 9,075 179 10,832
779.......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
781.......................................... 1.5 14.9 178.8 13,249 179 9,075 179 10,832
807.......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
815.......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
841.......................................... 1 14.9 119.2 8,832 119 6,050 119 7,221
973.......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1092......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1145......................................... 1 14.9 119.2 8,832 119 6,050 119 7,221
1305......................................... 1.5 14.9 178.8 13,249 179 9,075 179 10,832
1311......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1353......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1357......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1397......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1401......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1419......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1443......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1505......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1545......................................... 0.5 14.9 59.6 4,416 60 3,025 60 3,611
1549......................................... 2.5 14.9 298 22,081 298 15,125 298 18,054
----------------------------------------------------------------------------------------------------------
Totals................................... 19 343 2205 163,400 2205 111,923 2205 133,597
--------------------------------------------------------------------------------------------------------------------------------------------------------
* These numbers are subject to rounding error.
Using these yearly cost estimates, over 20 years $25.1 million in
man-hours would be spent on applying for and processing special
conditions, exemptions, and ELOS. However under the proposed rule, the
FAA believes that the need to demonstrate compliance through special
conditions, exemptions, or ELOS would largely be eliminated. Instead
new products will simply need to demonstrate compliance by following
consensus standards acceptable to the Administrator, or by submitting
their own novel demonstrations of compliance. As a conservative
estimate, the FAA estimates that special conditions, exemptions, and
ELOS would be reduced by half for a savings to the FAA and applicant of
roughly $12.6 million ($5.8 million present value). Savings by year is
shown in the chart below. The FAA asks for comment regarding the amount
of reduction in the alternative means of compliance.
[[Page 13503]]
In addition to this savings, there would also be additional
paperwork burden associated with proposed Sec. 23.200. As proposed,
this provision could result in a change to a limitation or a
performance number in the flight manual, which would reqire an update
to the training courseware or flight manual. Industry believes that
this proposed change could cost from $100,000 to $150,000. Therefore,
the FAA uses $125,000 (($100,000 + $150,000)/2) as an average cost for
this proposed change.
There would also be additional paperwork associated with this
requirement that is not part of the costs discussed above. The FAA
estimates the paperwork costs for these proposed provisions by
multiplying the number of hours the FAA estimates for each page of
paperwork, by the number of pages for the training courseware, or
flight manual, by the hourly rate of the person responsible for the
update. The Small Aircraft Directorate of the FAA provided average
hourly times and the number of additional pages of paperwork the
proposal would add. The FAA estimates that this section would add a
total of four pages to the training courseware and flight manual. The
FAA also estimates that it would take a part 23 certification engineer
eight hours to complete the one page required for each new type
certification. The eight hours to complete a page includes the
research, coordination, and review each document requires. Therefore,
the FAA estimates the total paperwork costs for proposed
controllability section would be about $1,939 (8 hours * 4 pages *
$60.58 per hour) in 2014 dollars.
The FAA is expecting part 23 airplane manufacturers to update their
engineering procedures manuals to reflect the changes from this
proposed rulemaking. However, most of the engineering procedures
manuals are not written around the requirements of part 23, but around
the requirements of part 21. Since the part 23 changes would have
minimal impact on the part 21 requirements, there should be little
change in the engineering procedures manuals. Conversations with
industry indicate that there may need to be some changes to the
engineering manuals to describe how the accepted means of compliance
must be related to the regulations. Depending on the complexity of each
company's manual, industry estimates that these changes could run from
about $50,000 up to $200,000. This would be a one-time cost per new
type certification.
Since the FAA is unable to determine the complexity of each
company's manual, we assume that the manufacturers of the two new part
23 reciprocating engine airplane type certifications, discussed in the
``Fleet Discussion'' section of the regulatory impact analysis, would
spend $50,000 to make the changes to the engineering manual. We also
assume that the one new part 23 turboprop airplane certification and
the two new part 23 turbojet airplane certifications, discussed in the
``Fleet Discussion'' section, would use the more complex and costly
approach of $200,000.
The FAA notes that either the simple approach or the more complex
approach to updating the manuals could also either take place in-house
or could be contracted out to a consultant.
Table 4 shows the total costs for the proposed changes to the
controllability section.
Table 4--Estimate Costs for Updating Engineering Manuals
[2014 $]
----------------------------------------------------------------------------------------------------------------
Number of
estimated Simple Complex
Airplane new type approach approach Total
certificates
----------------------------------------------------------------------------------------------------------------
Recip...................................................... 2 $50,000 $0 $100,000
Turboprop.................................................. 1 0 200,000 200,000
Turbojet................................................... 2 0 200,000 400,000
----------------------------------------------------
Total.................................................. ............ ........... ........... 700,000
----------------------------------------------------------------------------------------------------------------
* These numbers are subject to rounding error.
F. International Compatibility and Cooperation
In keeping with U.S. obligations under the Convention on
International Civil Aviation, it is FAA policy to conform to
International Civil Aviation Organization (ICAO) Standards and
Recommended Practices to the maximum extent practicable. The FAA has
reviewed the corresponding ICAO Standards and Recommended Practices and
has identified the following differences with these proposed
regulations. The ICAO Standards for small airplanes use weight and
propulsion to differentiate between some requirements. The proposed
regulations use certification levels and performance to differentiate
between some requirements. Furthermore, part 23 will still allow the
certification of airplanes up to 19,000 pounds. If this proposal is
adopted, the FAA intends to file these differences with ICAO. Executive
Order (EO) 13609, Promoting International Regulatory Cooperation, (77
FR 26413, May 4, 2012) promotes international regulatory cooperation to
meet shared challenges involving health, safety, labor, security,
environmental, and other issues and reduce, eliminate, or prevent
unnecessary differences in regulatory requirements. The FAA has
analyzed this action under the policy and agency responsibilities of
Executive Order 13609, Promoting International Regulatory Cooperation.
The agency has determined that this action would eliminate differences
between U.S. aviation standards and those of other CAAs by aligning the
revised part 23 standards with the new CS-23 standards that are being
developed concurrently by EASA. Several other CAAs are participating in
this effort and intend to either adopt the new part 23 or CS-23
regulations or revise their airworthiness standards to align with these
new regulations.
The Part 23 Reorganization ARC included participants from several
foreign CAAs and international members from almost every GA
manufacturer of both airplanes and avionics. It also included several
Light-Sport Aircraft manufacturers who are interested in certificating
their products using the airworthiness standards contained in part 23.
The rulemaking and means of compliance documents are international
efforts. Authorities from Europe, Canada, Brazil, China, and New
Zealand all are working to produce similar rules. These rules, while
not identical, are intended to allow the use
[[Page 13504]]
of the same set of industry developed means of compliance. Industry has
told that FAA that it is very costly to address the differences that
some contrived means of compliance imposes. If there is substantial
agreement between the major CAAs to use the same industry means of
compliance document, then U.S. manufactures expect a significant saving
for exporting their products.
Furthermore, this project is a harmonization project between the
FAA and EASA.
EASA has worked a parallel rulemaking program for CS-23. The FAA
provided comments to the EASA A-NPA The EASA and other authorities will
have an opportunity to comment on this NPRM when it is published. These
efforts will allow the FAA, EASA and other authorities to work toward a
harmonized set of regulations when the final rules are published.
G. Environmental Analysis
FAA Order 1050.1F identifies FAA actions that are categorically
excluded from preparation of an environmental assessment or
environmental impact statement under the National Environmental Policy
Act in the absence of extraordinary circumstances. The FAA has
determined this rulemaking action qualifies for the categorical
exclusion identified in paragraph 5-6.6 and involves no extraordinary
circumstances.
H. Regulations Affecting Intrastate Aviation in Alaska
Section 1205 of the FAA Reauthorization Act of 1996 (110 Stat.
3213) requires the Administrator, when modifying 14 CFR regulations in
a manner affecting intrastate aviation in Alaska, to consider the
extent to which Alaska is not served by transportation modes other than
aviation, and to establish appropriate regulatory distinctions. Because
this proposed rule would apply to GA airworthiness standards, it could,
if adopted, affect intrastate aviation in Alaska. The FAA, therefore,
specifically requests comments on whether there is justification for
applying the proposed rule differently in intrastate operations in
Alaska.
VIII. Executive Order Determination
A. Executive Order 13132, Federalism
The FAA has analyzed this proposed rule under the principles and
criteria of Executive Order 13132, Federalism. The agency has
determined that this action would not have a substantial direct effect
on the States, or the relationship between the Federal Government and
the States, or on the distribution of power and responsibilities among
the various levels of government, and, therefore, would not have
Federalism implications.
B. Executive Order 13211, Regulations That Significantly Affect Energy
Supply, Distribution, or Use
The FAA analyzed this proposed rule under Executive Order 13211,
Actions Concerning Regulations that Significantly Affect Energy Supply,
Distribution, or Use (May 18, 2001). The agency has determined that it
would not be a ``significant energy'' action under the executive order
and would not be likely to have a significant adverse effect on the
supply, distribution, or use of energy.
IX. Additional Information
A. Comments Invited
The FAA invites interested persons to participate in this
rulemaking by submitting written comments, data, or views. The agency
also invites comments relating to the economic, environmental, energy,
or federalism impacts that might result from adopting the proposals in
this document. The most helpful comments reference a specific portion
of the proposal, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, commenters should send only one copy of written
comments, or if comments are filed electronically, commenters should
submit only one time.
The FAA will file in the docket all comments it receives, as well
as a report summarizing each substantive public contact with FAA
personnel concerning this proposed rulemaking. Before acting on this
proposal, the FAA will consider all comments it receives on or before
the closing date for comments. The FAA will consider comments filed
after the comment period has closed if it is possible to do so without
incurring expense or delay. The agency may change this proposal in
light of the comments it receives.
Proprietary or Confidential Business Information: Commenters should
not file proprietary or confidential business information in the
docket. Such information must be sent or delivered directly to the
person identified in the FOR FURTHER INFORMATION CONTACT section of
this document, and marked as proprietary or confidential. If submitting
information on a disk or CD-ROM, mark the outside of the disk or CD-
ROM, and identify electronically within the disk or CD-ROM the specific
information that is proprietary or confidential.
Under 14 CFR 11.35(b), if the FAA is aware of proprietary
information filed with a comment, the agency does not place it in the
docket. It is held in a separate file to which the public does not have
access, and the FAA places a note in the docket that it has received
it. If the FAA receives a request to examine or copy this information,
it treats it as any other request under the Freedom of Information Act
(5 U.S.C. 552). The FAA processes such a request under Department of
Transportation procedures found in 49 CFR part 7.
B. Availability of Rulemaking Documents
An electronic copy of rulemaking documents may be obtained from the
Internet by--
1. Searching the Federal eRulemaking Portal (http://www.regulations.gov);
2. Visiting the FAA's Regulations and Policies Web page at http://www.faa.gov/regulations_policies or
3. Accessing the Government Printing Office's Web page at http://www.gpo.gov/fdsys/.
Copies may also be obtained by sending a request to the Federal
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence
Avenue SW., Washington, DC 20591, or by calling (202) 267-9680.
Commenters must identify the docket or notice number of this
rulemaking.
All documents the FAA considered in developing this proposed rule,
including economic analyses and technical reports, may be accessed from
the Internet through the Federal eRulemaking Portal referenced in item
(1) above.
Appendix 1 to the Preamble--Current to Proposed Regulations Cross-
Reference Table
The below cross-reference table is intended to permit easy access
from proposed to current regulations. The preamble is organized
topical, section-by-section, proposed to current regulations. This
table should assist the reader in following the section discussions
contained in the preamble.
[[Page 13505]]
----------------------------------------------------------------------------------------------------------------
Current section Title Proposed section Proposed title
----------------------------------------------------------------------------------------------------------------
Subpart A--General
----------------------------------------------------------------------------------------------------------------
23.1.............................. Applicability............. 23.1................. Applicability.
23.2.............................. Special retroactive ..................... --Deleted--
requirements.
23.3.............................. Airplane categories....... 23.5................. Certification of normal
category airplanes.
.......................... 23.10................ Accepted means of
compliance.
----------------------------------------------------------------------------------------------------------------
Subpart B--Flight
----------------------------------------------------------------------------------------------------------------
23.21............................. Proof of compliance....... 23.100............... Weight and center of
gravity.
23.23............................. Load distribution limits.. 23.100............... Weight and center of
gravity.
23.25............................. Weight limits............. 23.100............... Weight and center of
gravity.
23.29............................. Empty weight and 23.100............... Weight and center of
corresponding center of gravity.
gravity.
23.31............................. Removable ballast......... 23.100............... Weight and center of
gravity.
23.33............................. Propeller speed and pitch 23.900............... Powerplant installation.
limits.
23.45............................. Performance--General...... 23.105............... Performance.
23.49............................. Stalling speed............ 23.110............... Stall Speed.
23.51............................. Takeoff speeds............ 23.115............... Takeoff performance.
23.53............................. Takeoff performance....... 23.115............... Takeoff performance.
23.55............................. Accelerate-stop distance.. 23.115............... Takeoff performance.
23.57............................. Takeoff path.............. 23.115............... Takeoff performance.
23.59............................. Takeoff distance and 23.115............... Takeoff performance.
takeoff run.
23.61............................. Takeoff flight path....... 23.115............... Takeoff performance.
23.63............................. Climb: General............ 23.120............... Climb.
23.65............................. Climb: All engines 23.120............... Climb.
operating.
23.66............................. Takeoff climb: one engine 23.125............... Climb.
inoperative.
23.67............................. Climb: One engine 23.120............... Climb.
inoperative.
23.69............................. Enroute climb/descent..... 23.125............... Climb.
23.71............................. Glide: single engine 23.125............... Climb.
airplanes.
23.73............................. Reference landing approach 23.130............... Landing.
speed.
23.75............................. Landing distance.......... 23.130............... Landing.
23.77............................. Balked landing............ 23.120............... Climb.
23.141............................ Flight Characteristics-- 23.200............... Controllability.
General.
23.143............................ Controllability and 23.200............... Controllability.
Maneuverability--General.
23.145............................ Longitudinal control...... 23.200............... Controllability.
23.147............................ Directional and lateral 23.200............... Controllability.
control.
23.149............................ Minimum control speed..... 23.200............... Controllability.
23.151............................ Acrobatic maneuvers....... 23.200............... Controllability.
23.153............................ Control during landings... 23.200............... Controllability.
23.155............................ Elevator control force in 23.200............... Controllability.
maneuvers.
23.157............................ Rate of roll.............. 23.200............... Controllability.
23.161............................ Trim...................... 23.205............... Trim.
23.171............................ Stability--General........ 23.210............... Stability.
23.173............................ Static longitudinal 23.210............... Stability.
stability.
23.175............................ Demonstration of static 23.210............... Stability.
longitudinal stability.
23.177............................ Static directional and 23.210............... Stability.
lateral stability.
23.179............................ Instrument stick force 23.210............... Stability.
measurements.
23.181............................ Dynamic stability......... 23.210............... Stability.
23.201............................ Wings level stall......... 23.215............... Stall characteristics,
stall warning, and
spins.
23.203............................ Turning Flight and 23.215............... Stall characteristics,
accelerated turning stall warning, and
stalls. spins.
23.207............................ Stall Warning............. 23.215............... Stall characteristics,
stall warning, and
spins.
23.221............................ Spinning.................. 23.215............... Stall characteristics,
stall warning, and
spins.
23.231............................ Longitudinal stability and 23.220............... Ground handling.
control.
23.233............................ Directional stability and 23.220............... Ground handling.
control.
23.235............................ Operation on unpaved 23.220............... Ground handling.
surfaces.
23.237............................ Operation on water........ 23.220............... Ground handling.
23.239............................ Spray characteristics..... 23.220............... Ground handling.
23.251............................ Vibration and buffeting... 23.225............... Vibration, buffeting, and
high-speed
characteristics.
23.253............................ High speed characteristics 23.225............... Vibration, buffeting, and
high-speed
characteristics.
23.255............................ Out of trim 23.225............... Vibration, buffeting, and
characteristics. high-speed
characteristics.
23.230............... Performance and flight
characteristics
requirements for flight
in icing conditions.
----------------------------------------------------------------------------------------------------------------
[[Page 13506]]
Subpart C--Structure
----------------------------------------------------------------------------------------------------------------
23.301............................ Loads..................... 23.310, 23.330....... Structural design loads,
Limit and ultimate
loads.
(a)............................... .......................... 23.330............... Limit and ultimate loads.
(b)............................... .......................... 23.310............... Structural design loads.
(c)............................... .......................... 23.310............... Structural design loads.
(d)............................... .......................... 23.310............... Structural design loads.
23.302............................ Canard or tandem wing 23.310............... Structural design loads.
configurations.
23.303............................ Factors of safety......... 23.330............... Limit and ultimate loads.
23.305............................ Strength and deformation.. 23.400............... Structural strength.
23.305............... Interaction of systems
and structures.
23.307............................ Proof of structure........ 23.400............... Structure strength.
23.321............................ Flight Loads--General..... 23.310............... Structural design loads.
(a)............................... .......................... 23.310............... Structural design loads.
(b)............................... .......................... 23.300............... Structural design
envelope.
(c)............................... .......................... 23.300............... Structural design
envelope.
23.331............................ Symmetrical flight 23.310............... Structural design loads.
conditions.
23.333............................ Flight envelope........... 23.300............... Structural design
envelope.
(a)............................... .......................... 23.300............... Structural design
envelope.
(b)............................... .......................... 23.300............... Structural design
envelope.
(c)............................... .......................... 23.315............... Flight load conditions.
(d)............................... .......................... 23.300............... Structural design
envelope.
23.335............................ Design airspeeds.......... 23.300............... Structural design
envelope.
23.337............................ Limit maneuvering load 23.300............... Flight load conditions.
factors.
(a)............................... .......................... 23.300............... Structural design
envelope.
(b)............................... .......................... 23.300............... Structural design
envelope.
(c)............................... .......................... Means of Compliance..
23.341............................ Gust load factors......... 23.315............... Flight load conditions.
23.343............................ Design fuel loads......... 23.300............... Structural design
envelope.
(a)............................... .......................... 23.300............... Structural design
envelope.
(b)............................... .......................... 23.300............... Structural design
envelope.
(c)............................... .......................... Means of Compliance..
23.345............................ High lift devices......... 23.325............... Component loading
conditions.
23.347............................ Unsymmetrical flight loads 23.315............... Flight load conditions.
23.349............................ Rolling conditions........ 23.315............... Flight load conditions.
23.351............................ Yawing conditions......... 23.315............... Flight load conditions.
23.361............................ Engine torque............. 23.325............... Component loading
conditions.
23.363............................ Side load on engine mount. 23.325............... Component loading
conditions.
23.365............................ Pressurized cabin loads... 23.325............... Flight load conditions.
(e)............................... .......................... 23.405............... Structural durability.
23.367............................ Unsymmetrical loads due to 23.315............... Flight load conditions.
engine failure.
23.369............................ Rear lift truss........... Means of Compliance..
23.371............................ Gyroscopic and aerodynamic 23.325............... Component loading
loads. conditions.
23.373............................ Speed control devices..... 23.325............... Component loading
conditions.
23.391............................ Control surface loads..... 23.325............... Component loading
conditions.
23.393............................ Loads parallel to hinge 23.325............... Component loading
line. conditions.
23.395............................ Control system loads...... 23.325............... Component loading
conditions.
23.397............................ Limit control forces and 23.325............... Component loading
torques. conditions.
23.399............................ Dual control system....... 23.325............... Component loading
conditions.
23.405............................ Secondary control system.. 23.325............... Component loading
conditions.
23.407............................ Trim tab effects.......... 23.325............... Component loading
conditions.
23.409............................ Tabs...................... 23.325............... Component loading
conditions.
23.415............................ Ground gust conditions.... 23.325............... Component loading
conditions.
23.421............................ Balancing loads........... Means of Compliance..
23.423............................ Maneuvering loads......... 23.315............... Flight load conditions.
23.425............................ Gust loads................ 23.315............... Flight load conditions.
23.427............................ Unsymmetrical loads due to 23.315............... Flight load conditions.
engine failure.
23.441............................ Maneuvering loads......... 23.315............... Flight load conditions.
23.443............................ Gust loads................ 23.315............... Flight load conditions.
23.445............................ Outboard fins or winglets. Means of Compliance..
23.455............................ Ailerons.................. 23.325............... Component loading
conditions.
23.459............................ Special devices........... 23.325............... Component loading
conditions.
23.471............................ Ground Loads--General..... 23.320............... Ground and water load
conditions.
23.473............................ Ground load conditions and 23.320............... Ground and water load
assumptions. conditions.
23.477............................ Landing gear arrangement.. 23.320............... Ground and water load
conditions.
23.479............................ Level landing conditions.. 23.320............... Ground and water load
conditions.
23.481............................ Tail down landing 23.320............... Ground and water load
conditions. conditions.
23.483............................ One-wheel landing 23.320............... Ground and water load
conditions. conditions.
23.485............................ Side load conditions...... 23.320............... Ground and water load
conditions.
23.493............................ Braked roll conditions.... 23.320............... Ground and water load
conditions.
23.497............................ Supplementary conditions 23.320............... Ground and water load
for tail wheels. conditions.
23.499............................ Supplementary conditions 23.320............... Ground and water load
for nose wheels. conditions.
23.505............................ Supplementary conditions 23.320............... Ground and water load
for skiplanes. conditions.
[[Page 13507]]
23.507............................ Jacking loads............. 23.320............... Ground and water load
conditions.
23.509............................ Towing loads.............. 23.320............... Ground and water load
conditions.
23.511............................ Ground load: unsymmetrical 23.320............... Ground and water load
loads on multiple-wheel conditions.
units.
23.521............................ Water load conditions..... 23.320............... Ground and water load
conditions.
23.523............................ Design weights and center 23.320............... Ground and water load
of gravity positions. conditions.
23.525............................ Application of loads...... 23.320............... Ground and water load
conditions.
23.527............................ Hull and main float load 23.320............... Ground and water load
factors. conditions.
23.529............................ Hull and main float 23.320............... Ground and water load
landing conditions. conditions.
23.531............................ Hull and main float 23.320............... Ground and water load
takeoff conditions. conditions.
23.533............................ Hull and main float bottom 23.320............... Ground and water load
pressures. conditions.
23.535............................ Auxiliary float loads..... 23.320............... Ground and water load
conditions.
23.537............................ Seawing loads............. 23.320............... Ground and water load
conditions.
23.561............................ Emergency Landing 23.600............... Emergency conditions.
Conditions--General.
23.562............................ Emergency landing dynamic 23.600............... Emergency conditions.
conditions.
23.571............................ Metallic pressurized cabin 23.405............... Structural durability.
structures.
23.572............................ Metallic wing, empennage, 23.405............... Structural durability.
and associated structures.
23.573............................ Damage tolerance and 23.405............... Structural durability.
fatigue evaluation of
structure.
23.574............................ Metallic damage tolerance 23.405............... Structural durability.
and fatigue evaluation of
commuter category
airplanes.
23.575............................ Inspections and other 23.405............... Structural durability.
procedures.
----------------------------------------------------------------------------------------------------------------
Subpart D--Design and Construction
----------------------------------------------------------------------------------------------------------------
23.601............................ General................... 23.500............... Structural design.
23.603............................ Materials and workmanship. 23.500............... Structural design.
23.605............................ Fabrication methods....... 23.510............... Materials and processes.
23.607............................ Fasteners................. 23.505............... Protection of structure.
23.609............................ Protection of Structure... 23.505............... Protection of structure.
23.611............................ Accessibility............. 23.505............... Protection of structure.
23.613............................ Material strength 23.510............... Materials and processes.
properties and design
values.
23.619............................ Special factors........... 23.515............... Special factors of
safety.
23.621............................ Casting factors........... 23.515............... Special factors of
safety.
23.623............................ Bearing factors........... 23.515............... Special factors of
safety.
23.625............................ Fitting factors........... 23.515............... Special factors of
safety.
23.627............................ Fatigue strength.......... 23.405............... Structural durability.
23.629............................ Flutter................... 23.410............... Aeroelasticity.
23.641............................ Proof of strength......... Means of Compliance..
23.651............................ Proof of strength......... Means of Compliance..
23.655............................ Installation.............. Means of Compliance..
23.657............................ Hinges.................... 23.515............... Special factors of
safety.
23.659............................ Mass balance.............. 23.315............... Flight load conditions.
23.671............................ Control Surfaces--General.
(a)............................... .......................... 23.500............... Structural design.
(b)............................... .......................... 23.1305.............. Function and
installation.
23.672............................ Stability augmentation and 23.1305.............. Function and
automatic and power- installation.
operated systems.
23.673............................ Primary flight controls... 23.1305.............. Function and
installation.
23.675............................ Stops..................... 23.1305.............. Function and
installation.
23.677............................ Trim systems..............
(a)............................... .......................... 23.700............... Flight control systems.
(b)............................... .......................... 23.700............... Flight control systems.
(c)............................... .......................... 23.410............... Aeroelasticity.
(d)............................... .......................... 23.700............... Flight control systems.
23.679............................ Control system locks...... 23.1305.............. Function and
installation.
23.681(a)......................... Limit load static tests... 23.325(b)............ Component loading
conditions.
23.681(b)......................... Limit load static tests... 23.515............... Special factors of
safety.
23.683............................ Operation tests........... 23.500(d)............ Structural design.
23.685(a), (b), (c)............... Control system details.... 23.500(d)............ Structural design.
23.685(d)......................... Control system details.... 23.1305.............. Function and
installation.
23.687............................ Spring devices............ 23.410 and 23.500.... Aeroelasticity and
Structural design.
23.689............................ Cable systems.............
(a)............................... .......................... 23.700............... Flight control systems.
(b)............................... .......................... 23.325(b), 23.500(d). Component loading
conditions, Structural
design.
(c)............................... .......................... 23.325(b), 23.500(d). Component loading
conditions, Structural
design.
(d)............................... .......................... 23.325(b), 23.500(d). Component loading
conditions, Structural
design.
[[Page 13508]]
(e)............................... .......................... 23.325(b), 23.500(d). Component loading
conditions, Structural
design.
(f)............................... .......................... 23.700............... Flight control systems.
23.691............................ Artificial stall barrier
system.
(a)............................... .......................... 23.700............... Flight control systems.
(b)............................... .......................... 23.700............... Flight control systems.
(c)............................... .......................... 23.1305.............. Function and
installation.
(d)............................... .......................... 23.700............... Flight control systems.
(e)............................... .......................... 23.700............... Flight control systems.
(f)............................... .......................... 23.700............... Flight control systems.
(g)............................... .......................... 23.1315.............. Equipment, systems and
Installations.
23.693............................ Joints.................... 23.515............... Special factors of
safety.
23.697............................ Wing flap controls........
(a)............................... .......................... 23.700............... Flight control systems.
(b) and (c)....................... .......................... 23.200............... Controllability.
23.699............................ Wing flap position 23.1500.............. Flightcrew interface.
indicator.
23.701............................ Flap interconnection...... Means of Compliance..
23.703............................ Takeoff warning system....
(a)............................... .......................... 23.700............... Flight control systems.
(b)............................... .......................... 23.700............... Flight control systems.
(c)............................... .......................... Definition...........
23.721............................ General................... 23.910............... Powerplant installation
hazard assessment.
23.723............................ Shock absorption tests.... Means of Compliance..
23.725............................ Limit drop tests.......... Means of Compliance..
23.726............................ Ground load dynamic tests. Means of Compliance..
23.727............................ Reserve energy absorption Means of Compliance..
drop tests.
23.729............................ Landing gear extension and
retraction system.
(a)............................... .......................... 23.705............... Landing gear systems.
(b)............................... .......................... 23.705............... Landing gear systems.
(c)............................... .......................... 23.705............... Landing gear systems.
(d)............................... .......................... Means of Compliance..
(e)............................... .......................... 23.705............... Landing gear systems.
(f)............................... .......................... 23.1315.............. Equipment, systems and
installation.
(g)............................... .......................... Means of Compliance..
23.731............................ Wheels.................... 23.705............... Landing gear systems.
23.733............................ Tires.....................
(a)............................... .......................... 23.705............... Landing gear systems.
(b)............................... .......................... Means of Compliance..
(c)............................... .......................... Means of Compliance..
23.735............................ Brakes.................... 23.705...............
(a)............................... .......................... 23.705............... Landing gear systems.
(1)............................... .......................... Means of Compliance..
(2)............................... .......................... Means of Compliance..
(b)............................... .......................... 23.705............... Landing gear systems.
(c)............................... .......................... Means of Compliance..
(d)............................... .......................... 1315................. Equipment, systems and
installation.
(e)............................... .......................... 705.................. Landing gear systems.
(1)............................... .......................... Means of Compliance..
(2)............................... .......................... Means of Compliance..
23.737............................ Skis...................... 23.705............... Landing gear systems.
23.745............................ Nose/Tail wheel steering.. 23.1500.............. Flightcrew interface.
23.751............................ Main float buoyancy.......
(a)............................... .......................... 710.................. Buoyancy for seaplanes
and amphibians.
(b)............................... .......................... Means of Compliance..
23.753............................ Main float design......... 23.320............... Ground and water load
conditions.
23.755............................ Hulls..................... 23.710............... Buoyancy for seaplanes
and amphibians.
23.757............................ Auxiliary floats.......... 23.710............... Buoyancy for seaplanes
and amphibians.
23.771............................ Pilot compartment.........
(a)............................... .......................... 23.1500.............. Flightcrew interface.
(b)............................... .......................... 755.................. Occupant physical
environment.
(c)............................... .......................... 755.................. Occupant physical
environment.
23.773............................ Pilot compartment view....
(a)............................... .......................... 1500................. Flightcrew interface.
(b)............................... .......................... 23.755............... Occupant physical
environment.
23.775............................ Windshields and windows...
(a), (b), (c), (d)................ .......................... 23.755............... Occupant physical
environment.
(e)............................... .......................... Means of Compliance..
(f)............................... .......................... 23.1405.............. Flight in icing
conditions.
(g)............................... .......................... Means of Compliance..
(h)............................... .......................... 23.755............... Occupant physical
environment.
23.777............................ Cockpit controls.......... 23.1500.............. Flightcrew interface.
23.779............................ Motion and effect of 23.1500.............. Flightcrew interface.
cockpit controls.
23.781............................ Cockpit control knob shape 23.1500.............. Flightcrew interface.
[[Page 13509]]
23.783............................ Doors.....................
(a), (b), (c), (d)................ .......................... 23.750............... Means of egress and
emergency exits.
(e), (f), (g)..................... .......................... Means of Compliance..
23.785............................ Seats, berths, litters, 23.515 and 23.600.... Special factors of
safety belts, and safety, Emergency
shoulder harnesses. landing conditions.
23.787............................ Baggage and cargo 23.600(e)............ Emergency landing
compartments. conditions.
23.791............................ Passenger information 23.755............... Occupant physical
signs. environment.
23.803............................ Emergency evacuation......
(a)............................... .......................... 23.750............... Means of egress and
emergency exits.
(b)............................... .......................... Means of Compliance..
23.805............................ Flightcrew emergency exits 23.750............... Means of egress and
emergency exits.
23.807............................ Emergency exits...........
(a)(3), (b)(1), (c), (d)(1), .......................... Means of Compliance..
(d)(4).
Balance of 23.807................. .......................... 23.750............... Means of egress and
emergency exits.
23.811............................ Emergency exit marking.... 23.750............... Means of egress and
emergency exits.
23.812............................ Emergency lighting........ 23.750............... Means of egress and
emergency exits.
23.813............................ Emergency exit access.....
(a)............................... .......................... 23.750............... Means of egress and
emergency exits.
(b)............................... .......................... Means of Compliance..
CS-VLA 853........................ .......................... 23.750............... Means of egress and
emergency exits.
23.815............................ Width of aisle............ 23.750............... Means of egress and
emergency exits.
23.831............................ Ventilation............... 23.755............... Occupant physical
environment.
23.841(a), (b)(6), (c) ,(d)....... Pressurized cabins........ 23.755............... Occupant physical
environment.
(b)(1) through (5) and (7)........ .......................... Means of Compliance..
23.843............................ Pressurization tests...... 23.755............... Occupant physical
environment.
23.851............................ Fire extinguishers........
(a) and (b)....................... .......................... 23.800............... Fire protection outside
designated fire zones.
(c)............................... .......................... Means of Compliance..
23.853............................ Passenger and crew
compartment interiors.
(a)............................... .......................... 23.800............... Fire protection outside
designated fire zones.
(b)(c) and (d)(1)(2).............. .......................... Means of Compliance..
(d)(3)(i), (d)(3)(iii), (d)(3)(iv) .......................... 23.800............... Fire protection outside
designated fire zones.
(e)............................... .......................... 23.800............... Fire protection outside
designated fire zones.
(f)............................... .......................... 23.800............... Fire protection outside
designated fire zones.
23.855............................ Cargo and baggage 23.800............... Fire protection outside
compartment fire designated fire zones.
protection.
23.856............................ Thermal/acoustic 23.800............... Fire protection outside
insulation materials. designated fire zones.
23.859............................ Combustion heater fire
protection.
(a)............................... .......................... 23.800............... Fire protection outside
designated fire zones.
(b) thru (i)...................... .......................... Means of Compliance..
23.863............................ Flammable fluid fire
protection.
(a) and (d)....................... .......................... 23.800............... Fire protection outside
designated fire zones.
(b) and (c)....................... .......................... Means of Compliance.. Fire protection outside
designated fire zones.
23.865............................ Fire protection of flight 23.805............... Fire protection in
controls, engine mounts, designated fire zones.
and other flight
structure.
23.867............................ Electrical bonding and
protection against
lightning and static
electricity.
(a) and (c)....................... .......................... 23.810............... Lightning protection of
structure.
(b)............................... .......................... 23.1320.............. Electrical and electronic
system lightning
protection.
23.871............................ Leveling means............ Means of Compliance..
----------------------------------------------------------------------------------------------------------------
Subpart E--Powerplant
----------------------------------------------------------------------------------------------------------------
23.901............................ Installation.............. 23.900(c)............ Powerplant Installation.
(a), (b), (f)..................... .......................... 23.900(b)............
(c)............................... .......................... 23.900(b)............
(d) and (e)....................... .......................... 23.900(b)............ Note: In addition to
900(b) these rules are
covered under Part
33.63, 76, 77 and 78.
23.903............................ Engines...................
[[Page 13510]]
(a)............................... .......................... 23.900(c)............
(a)(2)............................ .......................... 23.940(b)............ Powerplant ice
protection.
(b)(c)............................ .......................... 23.910 and 23.920.... Powerplant installation
hazard assessment;
Reversing systems.
(b)(1)............................ .......................... 23.405(d)............ Structural durability.
(d) thru (g)...................... .......................... 23.925............... Powerplant operational
characteristics.
23.904............................ Automatic power reserve 23.915............... Automatic power control
system. systems.
23.905............................ Propellers................
(a)............................... .......................... 23.910(a)............ Powerplant installation
hazard assessment.
(b), (d), (g)..................... .......................... ..................... Note: Intent covered
under part 35.
(c)............................... .......................... 23.905............... Propeller installation.
(e)............................... .......................... 23.940............... Powerplant ice
protection.
(f)............................... .......................... 23.905............... Propeller installation.
(h)............................... .......................... 23.910............... Powerplant installation
hazard assessment.
23.907............................ Propeller vibration and ..................... Note: Intent covered
fatigue. under part 35.
23.909............................ Turbocharger systems......
(a) and (c)....................... .......................... 23.900............... Powerplant installation.
(b), (d), (e)..................... .......................... 23.910............... Powerplant installation
hazard assessment.
23.925............................ Propeller clearance....... 23.905(c)............ Installation.
23.929............................ Engine installation ice 23.940............... Powerplant ice
protection. protection.
23.933............................ Reversing systems......... 23.920...............
(a)............................... .......................... 23.920............... Reversing systems.
(b)............................... .......................... 23.920............... Reversing systems.
23.934............................ Turbojet and turbofan 23.920............... Note: In addition to Sec.
engine thrust reverser 23.920, this rule is
systems tests. covered under Sec.
33.97.
23.937............................ Turbopropeller-drag 23.920...............
limiting systems.
(a)............................... .......................... 23.920............... Reversing systems.
(b)............................... .......................... 23.920............... Reversing systems.
23.939............................ Powerplant operating 23.925............... In addition to 925 this
characteristics. rule is covered under
Part 33, subpart D and
F--Block Tests.
23.943............................ Negative acceleration..... 23.925............... Operational
characteristics.
23.951............................ Fuel System--General...... 23.930(a)(3).........
(a) and (b)....................... .......................... 23.930(a)(3)......... Fuel systems.
(c)............................... .......................... 23.930(a)(3).........
(d)............................... .......................... 23.930(a)(3)......... Intent covered under Part
34.
23.953............................ Fuel system independence.. 23.930............... Fuel systems.
23.954............................ Fuel system lightning 23.930............... Fuel systems.
protection.
23.955............................ Fuel flow................. 23.930............... Fuel systems.
23.957............................ Flow between 23.930(a)(7)......... Fuel systems.
interconnected tanks.
(a)............................... .......................... 23.930(a)(7).........
(b)............................... .......................... 23.930(a)(7).........
23.959............................ Unusable fuel supply...... 23.930(c)............ Hazard assessment.
23.961............................ Fuel system hot weather 23.930(a)(3)......... Fuel systems.
operation.
23.963............................ Fuel tank: general........
(a), (d), (e)..................... .......................... 23.930(b)(4)......... Fuel systems.
(b) and (c)....................... .......................... 23.930(b)(6).........
23.965............................ Fuel tank tests........... 23.930(b)(1).........
23.967............................ Fuel tank installation.... 23.930(b)(6).........
23.969............................ Fuel tank expansion space. 23.930(b)(6).........
23.971............................ Fuel tank sump............ 23.930(b)(6).........
23.973............................ Fuel tank filler 23.930(b)(6).........
connection.
23.975............................ Fuel tank vents and 23.930(b)(6).........
carburetor vapor vents.
(a)(1)............................ .......................... 23.940............... Powerplant ice
protection.
23.977............................ Fuel tank outlet.......... 23.930(b)(6)......... Fuel systems.
23.979............................ Pressure fueling systems.. 23.930(d)............
(a) and (b)....................... .......................... 23.930(d)............ Fuel systems.
(c) and (d)....................... .......................... 23.930(d)............ Hazard assessment.
23.991............................ Fuel pumps................ 23.930(a)(8).........
(a), (b), (c)..................... .......................... 23.930(a)(8)......... Fuel systems.
(d)............................... .......................... 23.910............... Powerplant installation
hazard assessment.
23.993............................ Fuel system lines and 23.930...............
fittings.
23.994............................ Fuel system components.... 23.930(a)(7)......... Hazard assessment.
23.995............................ Fuel valves and controls.. 23.930(d)............
(a)............................... .......................... 23.930(d)............ Powerplant installation.
(b) thru (g)...................... .......................... 23.930(d)............
23.997............................ Fuel strainer or filter... 23.930(a)............
(a) thru (d)...................... .......................... 23.930(a)(6)......... Fuel systems.
(e)............................... .......................... 23.950............... Powerplant ice
protection.
23.999............................ Fuel system drains........ 23.930(a)(4)......... Fuel systems.
23.1001........................... Fuel jettisoning system... 23.930(b)(5).........
(a)............................... .......................... 23.930(b)(5)......... Fuel systems.
(b) thru (g)...................... .......................... 23.930(b)(5).........
(h)............................... .......................... 23.910............... Powerplant installation
hazard assessment.
23.1011........................... General................... 23.935............... Intent covered under Part
33.
[[Page 13511]]
23.1013........................... Oil tanks................. 23.935(b)(1)......... Intent covered under Part
33.
23.1015........................... Oil tank tests............ 23.935(b)(1)......... Intent covered under Part
33.
23.1017........................... Oil lines and fittings.... 23.935(b)(1)......... Intent covered under Part
33.
23.1019........................... Oil strainer or filter.... 23.935(b)(2)......... Intent covered under Part
33.
23.1021........................... Oil system drains......... 23.935(b)(2)......... Intent covered under Part
33.
23.1023........................... Oil radiators............. 23.935(b)(1)......... Intent covered under Part
33.
23.1027........................... Propeller feathering 23.935(b)(2)......... Hazard assessment.
system.
23.1041........................... Cooling--General.......... 23.940(a)............ Intent covered under Part
33.
23.1043........................... Cooling tests............. 23.940(a)............ Intent covered under Part
33.
23.1045........................... Cooling test procedures 23.940(a)............ Intent covered under Part
for turbine engine 33.
powered airplanes.
23.1047........................... Cooling test procedures 23.940(a)............ Intent covered under Part
for reciprocating engine 33.
powered airplanes.
23.1061........................... Installation.............. 23.940(b)............ Intent covered under Part
33.
23.1063........................... Coolant tank tests........ 23.940(b)............ Intent covered under Part
33.
23.1091........................... Air induction system...... 23.945(a)............ Intent covered under Part
33.
23.1093........................... Induction system icing 23.940............... Powerplant ice
protection. protection.
23.1095........................... Carburetor deicing fluid 23.940............... Powerplant ice
flow rate. protection.
23.1097........................... Carburetor deicing fluid 23.940............... Powerplant ice
system capacity. protection.
23.1099........................... Carburetor deicing fluid 23.940............... Powerplant ice
system detail design. protection.
23.1101........................... Induction air preheater 23.935...............
design.
(a)............................... .......................... 23.935............... Powerplant induction and
exhaust systems.
(b) and (c)....................... .......................... 23.935...............
23.1103........................... Induction system ducts.... 23.935............... Powerplant induction and
exhaust systems.
23.1105........................... Induction system screens.. 23.935...............
23.1107........................... Induction system filters.. 23.935............... Powerplant induction and
exhaust systems.
23.1109........................... Turbocharger bleed air 23.910...............
system.
23.1111........................... Turbine engine bleed air 23.910...............
system.
(a) and (c)....................... .......................... 23.910............... Hazard assessment.
(b)............................... .......................... 23.910...............
23.1121........................... Exhaust System--General... 23.935...............
(a) thru (g)...................... .......................... 23.935............... Powerplant induction and
exhaust systems.
(h)............................... .......................... 23.910............... Hazard assessment.
23.1123........................... Exhaust system............ 23.910............... Hazard assessment.
23.1125........................... Exhaust heat exchangers... 23.910...............
(a)............................... .......................... 23.910............... Hazard assessment.
(b)............................... .......................... 23.910...............
23.1141........................... Powerplant controls: 23.1505(b)...........
general (a)(c)(g).
(b)(d)(e) and (f)......... 23.910............... Powerplant installation
hazard assessment.
23.1142........................... Auxiliary power unit 23.1500(b)...........
controls.
23.1143........................... Engine controls........... 23.1500(b)...........
23.1145........................... Ignition switches......... 23.1500(b)...........
23.1147........................... Mixture controls.......... 23.1500(b)...........
23.1149........................... Propeller speed and pitch 23.1500(b)...........
controls.
23.1153........................... Propeller feathering 23.1500(b)...........
controls.
23.1155........................... Turbine engine reverse 23.910 and 23.1500(b) Hazard assessment.
thrust and propeller
pitch settings below the
flight regime.
23.1157........................... Carburetor air temperature 23.1500(b)...........
controls.
23.1163........................... Powerplant accessories.... 23.910(a)............ Powerplant installation
hazard assessment.
(a), (c), (e)..................... .......................... 23.910(a)............
(b) and (d)....................... .......................... 23.910(a)............
23.1165........................... Engine ignition systems... Means of Compliance..
23.1181........................... Designated fire zones: 23.1000(a)........... Powerplant fire
regions included. protection.
23.1182........................... Nacelle areas behind 23.1000(b)...........
firewalls.
23.1183........................... Lines, fittings, and 23.1000(b)...........
components.
23.1189........................... Shutoff means............. 23.1000(c)...........
23.1191........................... Firewalls................. 23.1000(d)...........
(a) thru (e), (g), (h)............ .......................... 23.1000(d)...........
(f)............................... .......................... 23.910............... Powerplant installation
hazard assessment.
23.1192........................... Engine accessory 23.1000(d)...........
compartment diaphragm.
23.1193........................... Cowling and nacelle....... 23.1000(d)...........
(a) thru (e)...................... .......................... 23.1000(d)...........
(f) and (g)....................... .......................... 23.1000(d)........... Hazard assessment.
23.1195........................... Fire extinguishing systems 23.1000(e)...........
23.1197........................... Fire extinguishing agents. 23.1000(e)...........
23.1199........................... Extinguishing agent 23.1000(e)...........
containers.
23.1201........................... Fire extinguishing system 23.1000(e)...........
materials.
(a)............................... .......................... 23.1000(e)........... Hazard assessment.
(b)............................... .......................... 23.1000(e)...........
23.1203........................... Fire detector system...... 23.1000(f)...........
(a), (d), (e)..................... .......................... 23.1000(f)...........
(b) and (c)....................... .......................... 23.1000(f)........... Hazard assessment.
----------------------------------------------------------------------------------------------------------------
[[Page 13512]]
Subpart F--Equipment
----------------------------------------------------------------------------------------------------------------
23.1301........................... Function and installation.
(a)............................... .......................... 23.1300(a) and Airplane level systems
23.1305(a). requirements; Function
and installation.
(b)............................... .......................... 23.1305(a)(3)........ Function and
installation.
(c)............................... .......................... 23.1305(a)(2)........ Function and
installation.
23.1303........................... Flight and navigation 23.1300, 23.1310, Airplane level systems
instruments. 23.1305(b) and (c), requirements; Flight,
and 23.1330(c). navigation, and
powerplant instruments;
Function and
installation; System
power generation,
storage, and
distribution.
23.1305........................... Powerplant instruments.... 23.1300, 23.1310 and Airplane level systems
23.1305(c). requirements; Flight,
navigation, and
powerplant instruments;
Function and
installation.
23.1306........................... Electrical and electronic 23.1320.............. Electrical and electronic
system lightning system lightning
protection. protection.
23.1307........................... Miscellaneous equipment... 23.1300 and 23.1310.. Airplane level systems
requirements; Flight,
navigation, and
powerplant instruments.
23.1308........................... High-Intensity Radiated 23.1325.............. High-intensity Radiated
Fields (HIRF) protection. Fields (HIRF)
protection.
23.1309........................... Equipment, systems, and 23.1315.............. Equipment, systems, and
installations. installations.
(a)(1)............................ .......................... 23.1300(a)........... Airplane level systems
requirements.
(a)(2)............................ .......................... 23.1300(b)........... Airplane level systems
requirements.
(b)............................... .......................... ..................... --Deleted--.
(c)............................... .......................... 23.1315(b)........... Equipment, systems, and
installations.
(b)............................... .......................... 23.1305(c)........... Function and
installation.
23.1310........................... Power source capacity and 23.1330.............. System power generation,
distribution. storage, and
distribution.
23.1311........................... Electronic display 23.1300 and 23.1310.. Airplane level systems
instrument systems. requirements; Flight,
navigation, and
powerplant instruments.
23.1321........................... Arrangement and visibility 23.1300 and 23.1310.. Airplane level systems
requirements; Flight,
navigation, and
powerplant instruments.
23.1322........................... Warning, caution, and 23.1305(b) and (c)... Flight, navigation, and
advisory lights. powerplant instruments.
23.1323........................... Airspeed indicating system 23.1300, 23.1305, Airplane level systems
23.1310, and 1315. requirements; Function
and installation;
Flight, navigation, and
powerplant instruments;
and Equipment, systems,
and installations.
(d)............................... .......................... 23.1405.............. Flight in icing
conditions.
23.1325........................... Static pressure system.... 23.1300, 23.1310, and Airplane level systems
23.1315. requirements; Flight,
navigation, and
powerplant instruments;
and Equipment, systems,
and installations.
(b)(3) and (g).................... .......................... 1405................. Flight in icing
conditions.
23.1326........................... Pitot heat indication 23.1305.............. Function and
systems. installation.
23.1327........................... Magnetic direction 23.1300, 23.1305 and Airplane level systems
indicator. 23.1310. requirements; Function
and installation;
Flight, navigation, and
powerplant instruments.
23.1329........................... Automatic pilot system.... 23.1300, 23.1305 and Airplane level systems
23.1315. requirements; Function
and installation;
Equipment, systems, and
installations.
(a)............................... .......................... 23.1300 and 23.1315.. Airplane level systems
requirements; Equipment,
systems, and
installations.
(b)............................... .......................... 23.700 and 23.1500... Flight control systems;
Flightcrew interface.
(c)............................... .......................... 23.1305.............. Function and
installation.
(d)............................... .......................... 23.700 and 23.1500... Flight control systems;
Flightcrew interface.
(e), (f), (g)..................... .......................... 23.1300 and 23.1315.. Airplane level systems
requirements; Equipment,
systems, and
installations.
(h)............................... .......................... 23.1305.............. Function and
installation.
23.1331........................... Instruments using a power
source.
(a)............................... .......................... 23.1305(c)........... Function and
installation.
(b)............................... .......................... 23.1315(b) and Equipment, systems, and
23.1330(b). installations; System
power generation,
storage, and
distribution.
(c)............................... .......................... 23.1310(b)........... Flight, navigation, and
powerplant instruments.
23.1335........................... Flight director systems... 23.1300, 23.1305, Airplane level systems;
23.1315, and 23.1500. Function and
installation; Equipment
systems and
installations; and
Flightcrew interface.
23.1337........................... Powerplant instruments
installation.
(a)............................... .......................... 23.800(g)............ Fire protection outside
designated fire zones.
23.930............... Fuel systems.
(b)............................... .......................... 23.1305(c) and (d)... Function and
installation.
[[Page 13513]]
23.1310(a)........... Flight, navigation, and
powerplant instruments.
23.1315(b)........... Equipment, systems, and
installations.
(c)............................... .......................... 23.1315(b)........... Equipment, systems, and
installations.
(d)............................... .......................... 23.1305(c)........... Function and
installation.
23.1310(a)........... Flight, navigation, and
powerplant instruments.
23.1351........................... Electrical Systems-- 23.1300.............. Airplane level systems
General. requirements.
23.1305.............. Function and
installation.
23.1315.............. Equipment, systems, and
installations.
23.1330.............. System power generation,
storage, and
distribution.
23.1353........................... Storage battery design and 23.1300.............. Airplane level systems
installation. requirements.
23.1305.............. Function and
installation.
23.1315.............. Equipment, systems, and
installations.
23.1330.............. System power generation,
storage, and
distribution.
23.1357........................... Circuit protective devices 23.1300.............. Airplane level systems
requirements.
23.1305.............. Function and
installation.
23.1315.............. Equipment, systems, and
installations.
23.1330.............. System power generation,
storage, and
distribution.
23.1359........................... Electrical system fire
protection.
(a)............................... .......................... Means of Compliance..
(b)............................... .......................... 805.................. Flammability in
designated fire zones.
(c)............................... .......................... 800.................. Fire protection outside
designated fire zones.
23.1361........................... Master switch arrangement. 23.1300 and 23.1305.. Airplane level systems
requirements; Function
and installation.
23.1365........................... Electrical cables and 23.1305.............. Function and
equipment. installation.
(b)............................... .......................... 23.805............... Flammability in
designated fire zones.
(a), (c) thru (f)................. .......................... Means of Compliance..
23.1367........................... Switches..................
(a) and (b)....................... .......................... 23.1305.............. Function and
installation.
(c) and (d)....................... .......................... 23.1500.............. Flightcrew interface.
23.1381........................... Instrument lights.........
(a) and (b)....................... .......................... 23.1500.............. Flightcrew interface.
(c)............................... .......................... 23.1335.............. External and cockpit
lighting.
23.1383(a), (b), (c).............. Taxi and landing lights... 23.1335.............. External and cockpit
lighting.
(d)............................... Taxi and landing lights... 23.800............... Fire protection outside
designated fire zones.
23.1385(a), (b), (c).............. Position light system 23.1335.............. External and cockpit
installation. lighting.
(d)............................... Position light system 23.800............... Fire protection outside
installation. designated fire zones.
23.1387........................... Position light system 23.1335.............. External and cockpit
dihedral angles. lighting.
23.1389........................... Position light 23.1335.............. External and cockpit
distribution and lighting.
intensities.
23.1391........................... Minimum intensities in the 23.1335.............. External and cockpit
horizontal plane of lighting.
position lights.
23.1393........................... Minimum intensities in any 23.1335.............. External and cockpit
vertical plane of lighting.
position lights.
23.1395........................... Maximum intensities in 23.1335.............. External and cockpit
overlapping beams of lighting.
position lights.
23.1397........................... Color specifications...... 23.1335.............. External and cockpit
lighting.
23.1399........................... Riding light.............. 23.1335.............. External and cockpit
lighting.
23.1401........................... Anticollision light system
(a), (a)(1)....................... .......................... 23.1335.............. External and cockpit
lighting.
(a)(2)............................ .......................... Means of Compliance..
(b) thru (f)...................... .......................... 23.1335.............. External and cockpit
lighting.
23.1411........................... Safety Equipment-General..
(a), (b)(1)....................... .......................... 23.1400.............. Safety equipment.
(b)(2)............................ .......................... 23.600............... Emergency conditions.
23.1415........................... Ditching equipment........ 23.1400.............. Safety equipment.
(a), (c), (d)..................... .......................... 23.1400.............. Safety equipment.
(b)............................... .......................... Means of Compliance..
23.1416........................... Pneumatic de-icer boot 23.1300.............. Airplane level systems
system. requirements.
.......................... 23.1305.............. Function and
installation.
23.1419........................... Ice protection............ 23.230............... Flight in icing
conditions.
23.1405.............. Performance and flight
characteristics
requirements for flight
in icing conditions.
23.1431........................... Electronic equipment...... 23.1315.............. Equipment, systems and
installations.
23.1435........................... Hydraulic systems.........
(a)(4) and (b).................... .......................... 23.1410.............. Pressurized system
elements.
[[Page 13514]]
(a), (a)(1) through (3), (c)...... .......................... Means of Compliance..
23.1437........................... Accessories for 23.1410.............. Pressurized system
multiengine airplanes. elements.
23.1438........................... Pressurization and
pneumatic systems.
(a), (b).......................... .......................... 23.1410.............. Pressurized system
elements.
(c)............................... .......................... Means of Compliance..
23.1410(e)........... Pressurized system
elements.
23.1441........................... Oxygen equipment and
supply.
(a)............................... .......................... Means of Compliance..
(b)............................... .......................... 23.1315.............. Equipment, systems and
installation.
(c), (d), (e)..................... .......................... 23.755............... Occupant physical
environment.
23.1443(a), (b), (c).............. Minimum mass flow of 23.755............... Occupant physical
supplemental oxygen. environment.
(d)............................... .......................... Definition...........
23.1445........................... Oxygen distribution system 23.755............... Occupant physical
environment.
23.1447........................... Equipment standards for
oxygen dispensing units.
(a), (b), (c), (d), (f)........... .......................... 23.755............... Occupant physical
environment.
(e)............................... .......................... Means of Compliance..
23.1449........................... Means for determining use 23.755............... Occupant physical
of oxygen. environment.
23.1450........................... Chemical oxygen generators
(a)............................... .......................... Means of Compliance..
(b)............................... .......................... 23.1315.............. Equipment, systems and
installation.
(c)............................... .......................... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1451........................... Fire protection for oxygen 23.1315.............. Equipment, systems and
equipment. installation.
23.1453........................... Protection of oxygen 23.1315.............. Equipment, systems and
equipment from rupture. installation.
23.1457........................... Cockpit voice recorders... 23.1457.............. No Change.
23.1459........................... Flight recorders..........
(a)(1)............................ .......................... 23.1459.............. Flight data recorders.
(a)(2) thru (d)................... .......................... 23.1459.............. No Change.
23.1461........................... Equipment containing high 23.755............... Occupant physical
energy rotors. environment.
----------------------------------------------------------------------------------------------------------------
Subpart G--Operating Limitations and Information
----------------------------------------------------------------------------------------------------------------
23.1501........................... General................... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1505........................... Airspeed limitations...... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1507........................... Operating maneuvering 23.1505.............. Instrument markings,
speed. control markings, and
placards.
23.1511........................... Flap extended speed....... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1513........................... Minimum control speed..... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1519........................... Weight and center of 23.1505.............. Instrument markings,
gravity. control markings, and
placards.
23.1521........................... Powerplant limitations.... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1522........................... Auxiliary power unit 23.1505.............. Instrument markings,
limitations. control markings, and
placards.
23.1523........................... Minimum flight crew....... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1524........................... Maximum passenger seating 23.1505.............. Instrument markings,
configuration. control markings, and
placards.
23.1525........................... Kinds of operation........ 23.1300.............. Airplane level system
requirements.
23.1505.............. Instrument markings,
control markings, and
placards.
23.1527........................... Maximum operating altitude 23.1505.............. Instrument markings,
control markings, and
placards.
23.1529........................... Instructions for continued 23.1515.............. Instructions for
airworthiness. continued airworthiness.
23.1541........................... Marking and Placards-- 23.1505.............. Instrument markings,
General. control markings, and
placards.
23.1543........................... Instrument marking: 23.1505.............. Instrument markings,
general. control markings, and
placards.
23.1545........................... Airspeed indicator........ 23.1505.............. Instrument markings,
control markings, and
placards.
23.1547........................... Magnetic direction 23.1505.............. Instrument markings,
indicator. control markings, and
placards.
23.1549........................... Powerplant and auxiliary 23.1505.............. Instrument markings,
power unit instruments. control markings, and
placards.
23.1551........................... Oil quantity indicator.... 23.1505.............. Instrument markings,
control markings, and
placards.
[[Page 13515]]
23.1553........................... Fuel quantity indicator... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1555........................... Control markings.......... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1557........................... Miscellaneous marking and 23.1505.............. Instrument markings,
placards. control markings, and
placards.
23.1559........................... Operating limitations 23.1505.............. Instrument markings,
placard. control markings, and
placards.
23.1561........................... Safety equipment.......... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1563........................... Airspeed placards......... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1567........................... Flight maneuver placard... 23.1505.............. Instrument markings,
control markings, and
placards.
23.1581........................... Airplane Flight Manual and 23.1510.............. Airplane flight manual.
Approved Manual Material--
General.
23.1583........................... Operating limitations..... 23.1510.............. Airplane flight manual.
23.1585........................... Operating procedures...... 23.1510.............. Airplane flight manual.
23.1587........................... Performance information... 23.1510.............. Airplane flight manual.
23.1589........................... Loading information....... 23.1510.............. Airplane flight manual.
Appendix A........................ Simplified Design Load Means of Compliance..
Criteria.
Appendix B........................ [Reserved]................ ..................... --Deleted--
Appendix C........................ Basic Landing Conditions.. Means of Compliance..
Appendix D........................ Wheel Spin-Up and Spring- Means of Compliance..
Back Loads.
Appendix E........................ [Reserved]................ ..................... --Deleted--
Appendix F........................ Test Procedure............ Means of Compliance..
Appendix G........................ Instructions for Continued Appendix A........... Instructions for
Airworthiness. Continued Airworthiness.
Appendix H........................ Installation of An Means of Compliance..
Automatic Power Reserve
(APR) System.
Appendix I........................ Seaplane Loads............ Means of Compliance..
Appendix J........................ HIRF Environments and Means of Compliance..
Equipment HIRF Test
Levels.
----------------------------------------------------------------------------------------------------------------
Appendix 2 to the Preamble--Abbreviations and Acronyms Frequently Used
in This Document
AD Airworthiness Directive
AFM Airplane Flight Manual
ARC Aviation Rulemaking Committee
ASTM ASTM International
CAA Civil Aviation Authority
CAR Civil Aviation Regulations
Cf Confer (to identify a source or a usage citation for a word or
phrase)
CPS Certification Process Study
CS Certification Specification
CS-VLA Certification Specification--Very Light Aeroplanes
EASA European Aviation Safety Agency
ELOS Equivalent Level of Safety
FR Federal Register
GA General Aviation
HIRF High-Intensity Radiated Field
IFR Instrument Flight Rules
KCAS Knots Calibrated Airspeeds
LOC Loss of Control
NPRM Notice of Proposed Rulemaking
NTSB National Transportation Safety Board
OMB Office of Management and Budget
SAE SAE International
SLD Supercooled Large Droplet
TCDS Type Certificate Data Sheet
VA Design Maneuvering Speed
VC Design Cruising Speed
VD Design Dive Speed
VMC Minimum Control Speed
VMO/MMO Maximum Operating Limit Speed
VFR Visual Flight Rules
VSO Stalling speed or the minimum steady flight speed in the
landing configuration
List of Subjects
14 CFR Part 21
Aircraft, Aviation safety, Recording and recordkeeping
requirements.
14 CFR Part 23
Aircraft, Aviation Safety, Signs and symbols.
14 CFR Part 35
Aircraft, Aviation safety.
14 CFR Part 43
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
14 CFR Part 91
Air traffic control, Aircraft, Airmen, Airports, Aviation safety,
Reporting and recordkeeping requirements.
14 CFR Part 121
Aircraft, Airmen, Aviation safety, Reporting and recordkeeping
requirements.
14 CFR Part 135
Aircraft, Airmen, Aviation safety, Reporting and recordkeeping
requirements.
The Proposed Amendment
In consideration of the foregoing, the Federal Aviation
Administration proposes to amend chapter I of title 14, Code of Federal
Regulations as follows:
PART 21--CERTIFICATION PROCEDURES FOR PRODUCTS AND ARTICLES
0
1. The authority citation for part 21 is revised to read as follows:
Authority: 42 U.S.C. 7572; 49 U.S.C. 106(f), 106(g), 40105,
40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.
0
2. In Sec. 21.9, revise paragraphs (a)(5), (a)(6), (b), and (c)
introductory text, and add paragraph (a)(7) to read as follows:
Sec. 21.9 Replacement and modification articles.
(a) * * *
(5) Produced by an owner or operator for maintaining or altering
that owner or operator's product;
(6) Fabricated by an appropriately rated certificate holder with a
quality system, and consumed in the repair or alteration of a product
or article in
[[Page 13516]]
accordance with part 43 of this chapter; or
(7) Produced in any other manner approved by the FAA.
(b) Except as provided in paragraphs (a)(1), (a)(2) and (a)(7) of
this section, a person who produces a replacement or modification
article for sale may not represent that part as suitable for
installation on a type-certificated product.
(c) Except as provided in paragraphs (a)(1), (a)(2) and (a)(7) of
this section, a person may not sell or represent an article as suitable
for installation on an aircraft type-certificated under Sec.
21.25(a)(2) or Sec. 21.27 unless that article--
* * * * *
0
3. In Sec. 21.17, revise paragraph (a) introductory text to read as
follows:
Sec. 21.17 Designation of applicable regulations.
(a) Except as provided in Sec. Sec. 25.2, 27.2, 29.2, and in parts
26, 34, and 36 of this subchapter, an applicant for a type certificate
must show that the aircraft, aircraft engine, or propeller concerned
meets--
* * * * *
0
4. In Sec. 21.24, revise paragraph (a)(1)(i) to read as follows:
Sec. 21.24 Issuance of type certificate: primary category aircraft.
(a) * * *
(1) * * *
(i) Is unpowered; is an airplane powered by a single, naturally
aspirated engine with a 61-knot or less Vso stall speed as
defined in Sec. 23.49 of this chapter, at amendment 23-62, effective
on Jan 31, 2012; or is a rotorcraft with a 6-pound per square foot main
rotor disc loading limitation, under sea level standard day conditions;
* * * * *
0
5. In Sec. 21.35, revise paragraph (b)(2) to read as follows:
Sec. 21.35 Flight tests.
* * * * *
(b) * * *
(2) For aircraft to be certificated under this subchapter, except
gliders, and except for low-speed airplanes, as defined in part 23 of
this chapter, of 6,000 pounds or less maximum weight that are to be
certificated under part 23 of this chapter, to determine whether there
is reasonable assurance that the aircraft, its components, and its
equipment are reliable and function properly.
* * * * *
0
6. In Sec. 21.50, revise paragraph (b) to read as follows:
Sec. 21.50 Instructions for continued airworthiness and
manufacturer's maintenance manuals having airworthiness limitations
sections.
* * * * *
(b) The holder of a design approval, including either a type
certificate or supplemental type certificate for an aircraft, aircraft
engine, or propeller for which application was made after January 28,
1981, must furnish at least one set of complete Instructions for
Continued Airworthiness to the owner of each type aircraft, aircraft
engine, or propeller upon its delivery, or upon issuance of the first
standard airworthiness certificate for the affected aircraft, whichever
occurs later. The Instructions for Continued Airworthiness must be
prepared in accordance with Sec. Sec. 23.1515, 25.1529, 25.1729,
27.1529, 29.1529, 31.82, 33.4, 35.4, or part 26 of this subchapter, or
as specified in the applicable airworthiness criteria for special
classes of aircraft defined in Sec. 21.17(b), as applicable. If the
holder of a design approval chooses to designate parts as commercial,
it must include in the Instructions for Continued Airworthiness a list
of commercial parts submitted in accordance with the provisions of
paragraph (c) of this section. Thereafter, the holder of a design
approval must make those instructions available to any other person
required by this chapter to comply with any of the terms of those
instructions. In addition, changes to the Instructions for Continued
Airworthiness shall be made available to any person required by this
chapter to comply with any of those instructions.
* * * * *
0
7. In Sec. 21.101 revise paragraphs (b) introductory text, and (c) to
read as follows:
Sec. 21.101 Designation of applicable regulations.
* * * * *
(b) Except as provided in paragraph (g) of this section, if
paragraphs (b)(1), (2), or (3) of this section apply, an applicant may
show that the change and areas affected by the change comply with an
earlier amendment of a regulation required by paragraph (a) of this
section, and of any other regulation the FAA finds is directly related.
However, the earlier amended regulation may not precede either the
corresponding regulation incorporated by reference in the type
certificate, or any regulation in Sec. Sec. 25.2, 27.2, or Sec. 29.2
of this chapter that is related to the change. The applicant may show
compliance with an earlier amendment of a regulation for any of the
following:
* * * * *
(c) An applicant for a change to an aircraft (other than a
rotorcraft) of 6,000 pounds or less maximum weight, to a non-turbine
rotorcraft of 3,000 pounds or less maximum weight, to a simple, to a
level 1 low speed, or to a level 2 low speed airplane may show that the
change and areas affected by the change comply with the regulations
incorporated by reference in the type certificate. However, if the FAA
finds that the change is significant in an area, the FAA may designate
compliance with an amendment to the regulation incorporated by
reference in the type certificate that applies to the change and any
regulation that the FAA finds is directly related, unless the FAA also
finds that compliance with that amendment or regulation would not
contribute materially to the level of safety of the product or would be
impractical.
* * * * *
0
8. Revise part 23 to read as follows:
PART 23--AIRWORTHINESS STANDARDS: NORMAL CATEGORY AIRPLANES
Sec.
Subpart A--General
23.1 Applicability and definitions.
23.5 Certification of normal category airplanes.
23.10 Accepted means of compliance.
Subpart B--Flight
Performance
23.100 Weight and center of gravity.
23.105 Performance data.
23.110 Stall speed.
23.115 Takeoff performance.
23.120 Climb requirements.
23.125 Climb information.
23.130 Landing.
Flight Characteristics
23.200 Controllability.
23.205 Trim.
23.210 Stability.
23.215 Stall characteristics, stall warning, and spins.
23.220 Ground and water handling characteristics.
23.225 Vibration, buffeting, and high-speed characteristics.
23.230 Performance and flight characteristics requirements for
flight in icing conditions.
Subpart C--Structures
23.300 Structural design envelope.
23.305 Interaction of systems and structures.
Structural Loads
23.310 Structural design loads.
[[Page 13517]]
23.315 Flight load conditions.
23.320 Ground and water load conditions.
23.325 Component loading conditions.
23.330 Limit and ultimate loads.
Structural Performance
23.400 Structural strength.
23.405 Structural durability.
23.410 Aeroelasticity.
Design
23.500 Structural design.
23.505 Protection of structure.
23.510 Materials and processes.
23.515 Special factors of safety.
Structural Occupant Protection
23.600 Emergency conditions.
Subpart D--Design and Construction
23.700 Flight control systems.
23.705 Landing gear systems.
23.710 Buoyancy for seaplanes and amphibians.
Occupant System Design Protection
23.750 Means of egress and emergency exits.
23.755 Occupant physical environment.
Fire and High Energy Protection
23.800 Fire protection outside designated fire zones.
23.805 Fire protection in designated fire zones.
23.810 Lightning protection of structure.
Subpart E--Powerplant
23.900 Powerplant installation.
23.905 Propeller installation.
23.910 Powerplant installation hazard assessment.
23.915 Automatic power control systems.
23.920 Reversing systems.
23.925 Powerplant operational characteristics.
23.930 Fuel system.
23.935 Powerplant induction and exhaust systems.
23.940 Powerplant ice protection.
23.1000 Powerplant fire protection.
Subpart F--Equipment
23.1300 Airplane level systems requirements.
23.1305 Function and installation.
23.1310 Flight, navigation, and powerplant instruments.
23.1315 Equipment, systems, and installations.
23.1320 Electrical and electronic system lightning protection.
23.1325 High-intensity Radiated Fields (HIRF) protection.
23.1330 System power generation, storage, and distribution.
23.1335 External and cockpit lighting.
23.1400 Safety equipment.
23.1405 Flight in icing conditions.
23.1410 Pressurized system elements.
23.1457 Cockpit voice recorders.
23.1459 Flight data recorders.
Subpart G--Flightcrew Interface and Other Information
23.1500 Flightcrew interface.
23.1505 Instrument markings, control markings and placards.
23.1510 Airplane flight manual.
23.1515 Instructions for continued airworthiness.
Appendix A to Part 23--Instructions for Continued Airworthiness
Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704,
Pub. L. 113-53, 127 Stat. 584 (49 U.S.C. 44704) note.
Subpart A--General
Sec. 23.1 Applicability and definitions.
(a) This part prescribes airworthiness standards for the issuance
of type certificates, and changes to those certificates, for airplanes
in the normal category.
(b) For the purposes of this part, the following definitions apply:
(1) Continued safe flight and landing means an airplane is capable
of continued controlled flight and landing, possibly using emergency
procedures, without requiring exceptional pilot skill or strength. Upon
landing, some airplane damage may occur as a result of a failure
condition.
(2) Designated fire zone means a zone where catastrophic
consequences from fire in that zone must be mitigated by containing the
fire in that zone.
(3) Empty weight means the weight of the airplane with fixed
ballast, unusable fuel, full operating fluids, and other fluids
required for normal operation of airplane systems.
Sec. 23.5 Certification of normal category airplanes.
(a) Certification in the normal category applies to airplanes with
a passenger-seating configuration of 19 or less and a maximum
certificated takeoff weight of 19,000 pounds or less.
(b) Airplane certification levels are:
(1) Level 1--for airplanes with a maximum seating configuration of
0 to 1 passengers.
(2) Level 2--for airplanes with a maximum seating configuration of
2 to 6 passengers.
(3) Level 3--for airplanes with a maximum seating configuration of
7 to 9 passengers.
(4) Level 4--for airplanes with a maximum seating configuration of
10 to 19 passengers.
(c) Airplane performance levels are:
(1) Low speed--for airplanes with a VC or VMO
<= 250 Knots Calibrated Airspeed (KCAS) (and MMO <= 0.6).
(2) High speed--for airplanes with a VC or
VMO > 250 KCAS (or MMO > 0.6).
(d) Simple--Simple is defined as a level 1 airplane with a
VC or VMO <= 250 KCAS (and MMO <=
0.6), a VSO <= 45 KCAS and approved only for VFR operations.
(e) Airplanes not certified for aerobatics may be used to perform
any maneuver incident to normal flying, including--
(1) Stalls (except whip stalls); and
(2) Lazy eights, chandelles, and steep turns, in which the angle of
bank is not more than 60 degrees.
(f) Airplanes certified for aerobatics may be used to perform
maneuvers without limitations, other than those limitations necessary
to avoid damage or injury.
Sec. 23.10 Accepted means of compliance.
(a) An applicant must show the FAA how it will demonstrate
compliance with this part using a means of compliance, which may
include consensus standards, accepted by the Administrator.
(b) A person requesting acceptance of a means of compliance must
provide the means of compliance to the FAA in a form and manner
specified by the Administrator.
Subpart B--Flight
Performance
Sec. 23.100 Weight and center of gravity.
(a) The applicant must determine weights and centers of gravity
that provide limits for the safe operation of the airplane.
(b) The applicant must show compliance with each requirement of
this subpart at each combination of weight and center of gravity within
the airplane's range of loading conditions using tolerances acceptable
to the Administrator.
(c) The condition of the airplane at the time of determining its
empty weight and center of gravity must be well defined and easily
repeatable.
Sec. 23.105 Performance data.
(a) Unless otherwise prescribed, an airplane must meet the
performance requirements of this subpart in--
(1) Still air and standard atmospheric conditions at sea level for
all airplanes; and
(2) Ambient atmospheric conditions within the operating envelope
for--
(i) Level 1 high-speed and level 2 high-speed airplanes; and
(ii) Levels 3 and 4 airplanes.
(b) Unless otherwise prescribed, the applicant must develop the
performance data required by this subpart for the following conditions:
(1) Airport altitudes from sea level to 10,000 feet (3,048 meters);
and
(2) Temperatures from standard to 30[deg] Celsius above standard or
the maximum ambient atmospheric temperature at which compliance with
propulsion cooling requirements in climb is shown, if lower.
[[Page 13518]]
(c) The procedures used for determining takeoff and landing
distances must be executable consistently by pilots of average skill in
atmospheric conditions expected to be encountered in service.
(d) Performance data determined in accordance with paragraph (b) of
this section must account for losses due to atmospheric conditions,
cooling needs, and other demands on power sources.
Sec. 23.110 Stall speed.
The applicant must determine the airplane stall speed or the
minimum steady flight speed for each flight configuration used in
normal operations, including takeoff, climb, cruise, descent, approach,
and landing. Each determination must account for the most adverse
conditions for each flight configuration with power set at idle or zero
thrust.
Sec. 23.115 Takeoff performance.
(a) The applicant must determine airplane takeoff performance
accounting for--
(1) Stall speed safety margins;
(2) Minimum control speeds; and
(3) Climb gradients.
(b) For all airplanes, takeoff performance includes the
determination of ground roll and initial climb distance to 50 feet (15
meters) above the takeoff surface.
(c) For levels 1, 2, and 3 high-speed multiengine airplanes,
multiengine airplanes with a maximum takeoff weight greater than 12,500
pounds and level 4 multiengine airplanes, takeoff performance includes
a determination the following distances after a sudden critical loss of
thrust:
(1) Accelerate-stop;
(2) Ground roll and initial climb to 50 feet (15 meters) above the
takeoff surface; and
(3) Net takeoff flight path.
Sec. 23.120 Climb requirements.
The applicant must demonstrate the following minimum climb
performance out of ground effect:
(a) With all engines operating and in the initial climb
configuration--
(1) For levels 1 and 2 low speed airplanes, a climb gradient at sea
level of 8.3 percent for landplanes and 6.7 percent for seaplanes and
amphibians; and
(2) For levels 1 and 2 high-speed airplanes and all level 3
airplanes, a climb gradient at takeoff of 4 percent.
(b) After a critical loss of thrust on multiengine airplanes--
(1) For levels 1and 2 low-speed airplanes that do not meet single
engine crashworthiness requirements, a 1.5 percent climb gradient at a
pressure altitude of 5,000 feet (1,524 meters) in the cruise
configuration;
(2) For levels 1 and 2 high-speed airplanes, and level 3 low-speed
airplanes, a 1 percent climb gradient at 400 feet (122 meters) above
the takeoff surface with the landing gear retracted and flaps in the
takeoff configuration;
(3) For level 3 high-speed airplanes and all level 4 airplanes, a 2
percent climb gradient at 400 feet (122 meters) above the takeoff
surface with the landing gear retracted and flaps in the approach
configuration;
(4) At sea level for level 1 and level 2 low-speed airplanes; and
(5) At the landing surface for all other airplanes.
(c) For a balked landing, a climb gradient of 3 percent with--
(1) Takeoff power on each engine;
(2) Landing gear extended; and
(3) Flaps in the landing configuration.
Sec. 23.125 Climb information.
(a) The applicant must determine climb performance--
(1) For all single engine airplanes;
(2) For level 3 multiengine airplanes, following a critical loss of
thrust on takeoff in the initial climb configuration; and
(3) For all multiengine airplanes, during the enroute phase of
flight with all engines operating and after a critical loss of thrust
in the cruise configuration.
(b) For single engine airplanes, the applicant must determine the
glide performance of the airplane after a complete loss of thrust.
Sec. 23.130 Landing.
The applicant must determine the following, for standard
temperatures at each weight and altitude within the operational limits
for landing:
(a) The distance, starting from a height of 50 feet (15 meters)
above the landing surface, required to land and come to a stop, or for
water operations, reach a speed of 3 knots.
(b) The approach and landing speeds, configurations, and
procedures, which allow a pilot of average skill to meet the landing
distance consistently and without causing damage or injury.
Flight Characteristics
Sec. 23.200 Controllability.
(a) The airplane must be controllable and maneuverable, without
requiring exceptional piloting skill, alertness, or strength, within
the operating envelope--
(1) At all loading conditions for which certification is requested;
(2) During low-speed operations, including stalls;
(3) With any probable flight control or propulsion system failure;
and
(4) During configuration changes.
(b) The airplane must be able to complete a landing without causing
damage or serious injury, in the landing configuration at a speed of
VREF minus 5 knots using the approach gradient equal to the
steepest used in the landing distance determination.
(c) For levels 1 and 2 multiengine airplanes that cannot climb
after a critical loss of thrust, VMC must not exceed
VS1 or VS0 for all practical weights and
configurations within the operating envelope of the airplane.
(d) If the applicant requests certification of an airplane for
aerobatics, the applicant must demonstrate those aerobatic maneuvers
for which certification is requested and determine entry speeds.
Sec. 23.205 Trim.
(a) The airplane must maintain longitudinal, lateral, and
directional trim under the following conditions:
(1) For levels 1, 2, and 3 airplanes, in cruise, without further
force upon, or movement of, the primary flight controls or
corresponding trim controls by the pilot, or the flight control system.
(2) For level 4 airplanes in normal operations, without further
force upon, or movement of, the primary flight controls or
corresponding trim controls by the pilot, or the flight control system.
(b) The airplane must maintain longitudinal trim under the
following conditions:
(1) Climb.
(2) Level flight.
(3) Descent.
(4) Approach.
(c) Residual forces must not fatigue or distract the pilot during
likely emergency operations, including a critical loss of thrust on
multiengine airplanes.
Sec. 23.210 Stability.
(a) Airplanes not certified for aerobatics must--
(1) Have static longitudinal, lateral, and directional stability in
normal operations;
(2) Have dynamic short period and combined lateral-directional
stability in normal operations; and
(3) Provide stable control force feedback throughout the operating
envelope.
(b) No airplane may exhibit any divergent longitudinal stability
characteristic so unstable as to increase the pilot's workload or
otherwise endanger the airplane and its occupants.
[[Page 13519]]
Sec. 23.215 Stall characteristics, stall warning, and spins.
(a) The airplane must have controllable stall characteristics in
straight flight, turning flight, and accelerated turning flight with a
clear and distinctive stall warning that provides sufficient margin to
prevent inadvertent stalling.
(b) Levels 1 and 2 airplanes and level 3 single-engine airplanes,
not certified for aerobatics, must not have a tendency to inadvertently
depart controlled flight.
(c) Airplanes certified for aerobatics must have controllable stall
characteristics and the ability to recover within one and one-half
additional turns after initiation of the first control action from any
point in a spin, not exceeding six turns or any greater number of turns
for which certification is requested, while remaining within the
operating limitations of the airplane.
(d) Spin characteristics in airplanes certified for aerobatics must
not result in unrecoverable spins--
(1) With any use of the flight or engine power controls; or
(2) Due to pilot disorientation or incapacitation.
Sec. 23.220 Ground and water handling characteristics.
(a) For airplanes intended for operation on land or water, the
airplane must have controllable longitudinal and directional handling
characteristics during taxi, takeoff, and landing operations.
(b) For airplanes intended for operation on water, the following
must be established and included in the Airplane Flight Manual (AFM):
(1) The maximum wave height at which the aircraft demonstrates
compliance to paragraph (a) of this section. This wave height does not
constitute an operating limitation.
(2) Any necessary water handling procedures.
Sec. 23.225 Vibration, buffeting, and high-speed characteristics.
(a) Vibration and buffeting, for operations up to VD/
MD, must not interfere with the control of the airplane or
cause fatigue to the flightcrew. Stall warning buffet within these
limits is allowable.
(b) For high-speed airplanes and all airplanes with a maximum
operating altitude greater than 25,000 feet (7,620 meters) pressure
altitude, there must be no perceptible buffeting in cruise
configuration at 1g and at any speed up to VMO/
MMO, except stall buffeting.
(c) For high-speed airplanes, the applicant must determine the
positive maneuvering load factors at which the onset of perceptible
buffet occurs in the cruise configuration within the operational
envelope. Likely inadvertent excursions beyond this boundary must not
result in structural damage.
(d) High-speed airplanes must have recovery characteristics that do
not result in structural damage or loss of control, beginning at any
likely speed up to VMO/MMO, following--
(1) An inadvertent speed increase; and
(2) A high-speed trim upset.
Sec. 23.230 Performance and flight characteristics requirements for
flight in icing conditions.
(a) If an applicant requests certification for flight in icing
conditions as specified in part 1 of appendix C to part 25 of this
chapter and any additional atmospheric icing conditions for which an
applicant requests certification, the applicant must demonstrate the
following:
(1) Compliance with each requirement of this subpart, except those
applicable to spins and any that must be demonstrated at speeds in
excess of--
(i) 250 knots CAS;
(ii) VMO or MMO; or
(iii) A speed at which the applicant demonstrates the airframe will
be free of ice accretion.
(2) The stall warning for flight in icing conditions and non-icing
conditions is the same.
(b) If an applicant requests certification for flight in icing
conditions, the applicant must provide a means to detect any icing
conditions for which certification is not requested and demonstrate the
aircraft's ability to avoid or exit those conditions.
(c) The applicant must develop an operating limitation to prohibit
intentional flight, including takeoff and landing, into icing
conditions for which the airplane is not certified to operate.
Subpart C--Structures
Sec. 23.300 Structural design envelope.
The applicant must determine the structural design envelope, which
describes the range and limits of airplane design and operational
parameters for which the applicant will show compliance with the
requirements of this subpart. The applicant must account for all
airplane design and operational parameters that affect structural
loads, strength, durability, and aeroelasticity, including:
(a) Structural design airspeeds and Mach numbers, including--
(1) The design maneuvering airspeed, VA, which may be no
less than the airspeed at which the airplane will stall at the maximum
design maneuvering load factor;
(2) The design cruising airspeed, VC or MC,
which may be no less than the maximum speed expected in normal
operations;
(3) The design dive airspeed, VD or MD, which
is the airspeed that will not be exceeded by inadvertent airspeed
increases when operating at VC or MC;
(4) Any other design airspeed limitations required for the
operation of high lift devices, landing gear, and other equipment or
devices; and
(5) For level 4 airplanes, a rough air penetration speed,
VB.
(b) Design maneuvering load factors not less than those, which
service history shows, may occur within the structural design envelope.
(c) Inertial properties including weight, center of gravity, and
mass moments of inertia, accounting for--
(1) All weights from the airplane empty weight to the maximum
weight; and
(2) The weight and distribution of occupants, payload, and fuel.
(d) Range of motion for control surfaces, high lift devices, or
other moveable surfaces, including tolerances.
(e) All altitudes up to the maximum altitude.
Sec. 23.305 Interaction of systems and structures.
For airplanes equipped with systems that affect structural
performance, either directly or as a result of failure or malfunction,
the applicant must account for the influence and failure conditions of
these systems when showing compliance with the requirements of this
subpart.
Structural Loads
Sec. 23.310 Structural design loads.
The applicant must:
(a) Determine structural design loads resulting from any externally
or internally applied pressure, force, or moment which may occur in
flight, ground and water operations, ground and water handling, and
while the airplane is parked or moored.
(b) Determine the loads required by paragraph (a) of this section
at all critical combinations of parameters, on and within the
boundaries of the structural design envelope.
(c) The magnitude and distribution of these loads must be based on
physical principles and may be no less than service history shows will
occur within the structural design envelope.
Sec. 23.315 Flight load conditions.
The applicant must determine the structural design loads resulting
from the following flight conditions:
[[Page 13520]]
(a) Vertical and horizontal atmospheric gusts where the magnitude
and gradient of these gusts are based on measured gust statistics.
(b) Symmetric and asymmetric maneuvers.
(c) For canted lifting surfaces, vertical and horizontal loads
acting simultaneously resulting from gust and maneuver conditions.
(d) For multiengine airplanes, failure of the powerplant unit which
results in the most severe structural loads.
Sec. 23.320 Ground and water load conditions.
The applicant must determine the structural design loads resulting
from the following ground and water operations:
(a) For airplanes intended for operation on land--taxi, takeoff,
landing, and ground handling conditions occurring in normal and adverse
attitudes and configurations.
(b) For airplanes intended for operation on water--taxi, takeoff,
landing, and water handling conditions occurring in normal and adverse
attitudes and configurations in the most severe sea conditions expected
in operation.
(c) Jacking and towing conditions.
Sec. 23.325 Component loading conditions.
The applicant must determine the structural design loads acting on:
(a) Each engine mount and its supporting structure resulting from
engine operation combined with gusts and maneuvers.
(b) Each flight control and high lift surface, their associated
system and supporting structure resulting from--
(1) The inertia of each surface and mass balance attachment;
(2) Gusts and maneuvers;
(3) Pilot or automated system inputs;
(4) System induced conditions, including jamming and friction; and
(5) Ground operations, including downwind taxi and ground gusts.
(c) A pressurized cabin resulting from the pressurization
differential--
(1) From zero up to the maximum relief valve setting combined with
gust and maneuver loads;
(2) From zero up to the maximum relief valve setting combined with
ground and water loads if the airplane may land with the cabin
pressurized; and
(3) At the maximum relief valve setting multiplied by 1.33,
omitting all other loads.
Sec. 23.330 Limit and ultimate loads.
Unless special or other factors of safety are necessary to meet the
requirements of this subpart, the applicant must determine--
(a) The limit loads, which are equal to the structural design
loads; and
(b) The ultimate loads, which are equal to the limit loads
multiplied by a 1.5 factor of safety.
Structural Performance
Sec. 23.400 Structural strength.
The applicant must demonstrate that the structure will support:
(a) Limit loads without--
(1) Interference with the operation of the airplane; and
(2) Detrimental permanent deformation.
(b) Ultimate loads.
Sec. 23.405 Structural durability.
(a) The applicant must develop and implement procedures to prevent
structural failures due to foreseeable causes of strength degradation,
which could result in serious or fatal injuries, loss of the airplane,
or extended periods of operation with reduced safety margins. The
Instructions for Continued Airworthiness must include procedures
developed under this section.
(b) If a pressurized cabin has two or more compartments separated
by bulkheads or a floor, the applicant must design the structure for a
sudden release of pressure in any compartment that has a door or
window, considering failure of the largest door or window opening in
the compartment.
(c) For airplanes with maximum operating altitude greater than
41,000 feet, the procedures developed for compliance to paragraph (a)
of this section must be capable of detecting damage to the pressurized
cabin structure before the damage could result in rapid decompression
that would result in serious or fatal injuries.
(d) The airplane must be capable of continued safe flight and
landing with structural damage caused by high-energy fragments from an
uncontained engine or rotating machinery failure.
Sec. 23.410 Aeroelasticity.
(a) The airplane must be free from flutter, control reversal, and
divergence--
(1) At all speeds within and sufficiently beyond the structural
design envelope;
(2) For any configuration and condition of operation;
(3) Accounting for critical degrees of freedom; and
(4) Accounting for any critical failures or malfunctions.
(b) The applicant must establish and account for tolerances for all
quantities that affect flutter.
Design
Sec. 23.500 Structural design.
(a) The applicant must design each part, article, and assembly for
the expected operating conditions of the airplane.
(b) Design data must adequately define the part, article, or
assembly configuration, its design features, and any materials and
processes used.
(c) The applicant must determine the suitability of each design
detail and part having an important bearing on safety in operations.
(d) The control system must be free from jamming, excessive
friction, and excessive deflection when--
(1) The control system and its supporting structure are subjected
to loads corresponding to the limit airloads;
(2) The primary controls are subjected to the lesser of the limit
airloads or limit pilot forces; and
(3) The secondary controls are subjected to loads not less than
those corresponding to maximum pilot effort.
Sec. 23.505 Protection of structure.
(a) The applicant must protect each part of the airplane, including
small parts such as fasteners, against deterioration or loss of
strength due to any cause likely to occur in the expected operational
environment.
(b) Each part of the airplane must have adequate provisions for
ventilation and drainage.
(c) For each part that requires maintenance, preventive
maintenance, or servicing, the applicant must incorporate a means into
the aircraft design to allow such actions to be accomplished.
Sec. 23.510 Materials and processes.
(a) The applicant must determine the suitability and durability of
materials used for parts, articles, and assemblies, the failure of
which could prevent continued safe flight and landing. The applicant
must account for the effects of likely environmental conditions
expected in service.
(b) The methods and processes of fabrication and assembly used must
produce consistently sound structures. If a fabrication process
requires close control to reach this objective, the applicant must
perform the process under an approved process specification.
(c) Except as provided in paragraphs (f) and (g) of this section,
the applicant must select design values that ensure material strength
with probabilities that account for the criticality of the structural
element. Design values must
[[Page 13521]]
account for the probability of structural failure due to material
variability.
(d) If material strength properties are required, a determination
of those properties must be based on sufficient tests of material
meeting specifications to establish design values on a statistical
basis.
(e) If thermal effects are significant on an essential component or
structure under normal operating conditions, the applicant must
determine those effects on allowable stresses used for design.
(f) Design values, greater than the minimums specified by this
section, may be used, where only guaranteed minimum values are normally
allowed, if a specimen of each individual item is tested before use to
determine that the actual strength properties of that particular item
will equal or exceed those used in the design.
(g) An applicant may use other material design values if approved
by the Administrator.
Sec. 23.515 Special factors of safety.
(a) The applicant must determine a special factor of safety for any
critical design value that is--
(1) Uncertain;
(2) Used for a part, article, or assembly that is likely to
deteriorate in service before normal replacement; or
(3) Subject to appreciable variability because of uncertainties in
manufacturing processes or inspection methods.
(b) The applicant must determine a special factor of safety using
quality controls and specifications that account for each--
(1) Structural application;
(2) Inspection method;
(3) Structural test requirement;
(4) Sampling percentage; and
(5) Process and material control.
(c) The applicant must apply any special factor of safety in the
design for each part of the structure by multiplying each limit load
and ultimate load by the special factor of safety.
Structural Occupant Protection
Sec. 23.600 Emergency conditions.
(a) The airplane, even when damaged in an emergency landing, must
protect each occupant against injury that would preclude egress when--
(1) Properly using safety equipment and features provided for in
the design;
(2) The occupant experiences ultimate static inertia loads likely
to occur in an emergency landing; and
(3) Items of mass, including engines or auxiliary power units
(APUs), within or aft of the cabin, that could injure an occupant,
experience ultimate static inertia loads likely to occur in an
emergency landing.
(b) The emergency landing conditions specified in paragraph (a) of
this section, must--
(1) Include dynamic conditions that are likely to occur with an
impact at stall speed, accounting for variations in aircraft mass,
flight path angle, flight pitch angle, yaw, and airplane configuration,
including likely failure conditions at impact; and
(2) Not exceed established human injury criteria for human
tolerance due to restraint or contact with objects in the airplane.
(c) The airplane must have seating and restraints for all
occupants. The airplane seating, restraints, and cabin interior must
account for likely flight and emergency landing conditions.
(d) Each occupant restraint system must consist of a seat, a method
to restrain the occupant's pelvis and torso, and a single action
restraint release. For all flight and ground loads during normal
operation and any emergency landing conditions, the restraint system
must perform its intended function and not create a hazard that could
cause a secondary injury to an occupant. The restraint system must not
prevent occupant egress or interfere with the operation of the airplane
when not in use.
(e) Each baggage and cargo compartment must--
(1) Be designed for its maximum weight of contents and for the
critical load distributions at the maximum load factors corresponding
to the flight and ground load conditions determined under this part;
(2) Have a means to prevent the contents of the compartment from
becoming a hazard by impacting occupants or shifting; and
(3) Protect any controls, wiring, lines, equipment, or accessories
whose damage or failure would affect operations.
Subpart D--Design and Construction
Sec. 23.700 Flight control systems.
(a) The applicant must design airplane flight control systems to:
(1) Prevent major, hazardous, and catastrophic hazards, including--
(i) Failure;
(ii) Operational hazards;
(iii) Flutter;
(iv) Asymmetry; and
(v) Misconfiguration.
(2) Operate easily, smoothly, and positively enough to allow normal
operation.
(b) The applicant must design trim systems to:
(1) Prevent inadvertent, incorrect, or abrupt trim operation.
(2) Provide a means to indicate--
(i) The direction of trim control movement relative to airplane
motion;
(ii) The trim position with respect to the trim range;
(iii) The neutral position for lateral and directional trim; and
(iv) For all airplanes, except simple airplanes, the range for
takeoff for all applicant requested center of gravity ranges and
configurations.
(3) Except for simple airplanes, provide control for continued safe
flight and landing when any one connecting or transmitting element in
the primary flight control system fails.
(4) Limit the range of travel to allow safe flight and landing, if
an adjustable stabilizer is used.
(c) For an airplane equipped with an artificial stall barrier
system, the system must--
(1) Prevent uncommanded control or thrust action; and
(2) Provide for a preflight check.
(d) For level 3 high-speed and all level 4 airplanes, an applicant
must install a takeoff warning system on the airplane unless the
applicant demonstrates the airplane, for each configuration, can
takeoff at the limits of the trim and flap ranges.
Sec. 23.705 Landing gear systems.
(a) For airplanes with retractable landing gear:
(1) The landing gear and retracting mechanism, including the wheel
well doors, must be able to withstand operational and flight loads.
(2) The airplane must have--
(i) A positive means to keep the landing gear extended;
(ii) A secondary means of extension for landing gear that cannot be
extended using the primary means;
(iii) A means to inform the pilot that each landing gear is secured
in the extended and retracted positions; and
(iv) Except for airplanes intended for operation on water, a
warning to the pilot if the thrust and configuration is selected for
landing and the landing gear is not fully extended and locked.
(3) If the landing gear bay is used as the location for equipment
other than the landing gear, that equipment must be designed and
installed to avoid damage from tire burst and from items that may enter
the landing gear bay.
(b) The design of each landing gear wheel, tire, and ski must
account for critical loads, including those experienced during landing
and rejected takeoff.
(c) A reliable means of stopping the airplane must provide kinetic
energy absorption within the airplane's design specifications for
landing.
[[Page 13522]]
(d) For levels 3 and 4 multiengine airplanes, the braking system
must provide kinetic energy absorption within the airplane's design
specifications for rejected takeoff.
Sec. 23.710 Buoyancy for seaplanes and amphibians.
Airplanes intended for operations on water, must--
(a) Provide buoyancy of 80 percent in excess of the buoyancy
required to support the maximum weight of the airplane in fresh water;
and
(b) Have sufficient watertight compartments so the airplane will
stay afloat at rest in calm water without capsizing if any two
compartments of any main float or hull are flooded.
Occupant System Design Protection
Sec. 23.750 Means of egress and emergency exits.
(a) The airplane cabin exit design must provide for evacuation of
the airplane within 90 seconds in conditions likely to occur following
an emergency landing. Likely conditions exclude ditching for all but
levels 3 and 4 multiengine airplanes.
(b) Each exit must have a means to be opened from both inside and
outside the airplane, when the internal locking mechanism is in the
locked and unlocked position. The means of opening must be simple,
obvious, and marked inside and outside the airplane.
(c) Airplane evacuation paths must protect occupants from serious
injury from the propulsion system.
(d) Each exit must not be obstructed by a seat or seat back, unless
the seat or seat back can be easily moved in one action to clear the
exit.
(e) Airplanes certified for aerobatics must have a means to egress
the airplane in flight.
(f) Doors, canopies, and exits must be protected from opening
inadvertently in flight.
Sec. 23.755 Occupant physical environment.
(a) The applicant must design the airplane to--
(1) Allow clear communication between the flightcrew and
passengers;
(2) Provide a clear, sufficiently undistorted external view to
enable the flightcrew to perform any maneuvers within the operating
limitations of the airplane;
(3) Protect the pilot from serious injury due to high energy
rotating failures in systems and equipment; and
(4) Protect the occupants from serious injury due to damage to
windshields, windows, and canopies.
(b) For level 4 airplanes, each windshield and its supporting
structure directly in front of the pilot must--
(1) Withstand, without penetration, the impact equivalent to a two-
pound bird when the velocity of the airplane is equal to the airplane's
maximum approach flap speed; and
(2) Allow for continued safe flight and landing after the loss of
vision through any one panel.
(c) The airplane must provide each occupant with air at a
breathable pressure, free of hazardous concentrations of gases and
vapors, during normal operations and likely failures.
(d) If an oxygen system is installed in the airplane, it must
include--
(1) A means to allow the flightcrew to determine the quantity of
oxygen available in each source of supply on the ground and in flight;
(2) A means to determine whether oxygen is being delivered; and
(3) A means to permit the flightcrew to turn on and shut off the
oxygen supply at any high-pressure source in flight.
(e) If a pressurization system is installed in the airplane, it
must include--
(1) A warning if an unsafe condition exists; and
(2) A pressurization system test.
Fire and High Energy Protection
Sec. 23.800 Fire protection outside designated fire zones.
Outside designated fire zones:
(a) The following materials must be self-extinguishing--
(1) Insulation on electrical wire and electrical cable;
(2) For levels 1, 2, and 3 airplanes, materials in the baggage and
cargo compartments inaccessible in flight; and
(3) For level 4 airplanes, materials in the cockpit, cabin,
baggage, and cargo compartments.
(b) The following materials must be flame resistant--
(1) For levels 1, 2 and 3 airplanes, materials in each compartment
accessible in flight; and
(2) Any electrical cable installation that would overheat in the
event of circuit overload or fault.
(c) Thermal acoustic materials, if installed, must not be a flame
propagation hazard.
(d) Sources of heat that are capable of igniting adjacent objects
must be shielded and insulated to prevent such ignition.
(e) For level 4 airplanes, each baggage and cargo compartment
must--
(1) Be located where a fire would be visible to the pilots, or
equipped with a fire detection system and warning system; and
(2) Be accessible for the manual extinguishing of a fire, have a
built-in fire extinguishing system, or be constructed and sealed to
contain any fire within the compartment.
(f) There must be a means to extinguish any fire in the cabin such
that--
(1) The pilot, while seated, can easily access the fire
extinguishing means; and
(2) For levels 3 and 4 airplanes, passengers have a fire
extinguishing means available within the passenger compartment.
(g) Each area where flammable fluids or vapors might escape by
leakage of a fluid system must--
(1) Be defined; and
(2) Have a means to make fluid and vapor ignition, and the
resultant hazard, if ignition occurs, improbable.
(h) Combustion heater installations must be protected from
uncontained fire.
Sec. 23.805 Fire protection in designated fire zones.
Inside designated fire zones:
(a) Flight controls, engine mounts, and other flight structures
within or adjacent to those zones must be capable of withstanding the
effects of a fire.
(b) Engines must remain attached to the airplane in the event of a
fire or electrical arcing.
(c) Terminals, equipment, and electrical cables used during
emergency procedures must be fire-resistant.
Sec. 23.810 Lightning protection of structure.
(a) For airplanes approved for instrument flight rules, no
structural failure preventing continued safe flight and landing may
occur from exposure to the direct effects of lightning.
(b) Airplanes approved only for visual flight rules must achieve
lightning protection by following FAA accepted design practices.
Subpart E--Powerplant
Sec. 23.900 Powerplant installation.
(a) For the purpose of this subpart, the airplane powerplant
installation must include each component necessary for propulsion,
affects propulsion safety, or provides auxiliary power to the airplane.
(b) The applicant must construct and arrange each powerplant
installation to account for likely hazards in operation and
maintenance.
(c) Except for simple airplanes, each aircraft power unit must be
type certificated.
Sec. 23.905 Propeller installation.
(a) Except for simple airplanes, each propeller must be type
certificated.
[[Page 13523]]
(b) Each pusher propeller must be marked so that it is conspicuous
under daylight conditions.
(c) Each propeller installation must account for vibration and
fatigue.
Sec. 23.910 Powerplant installation hazard assessment.
The applicant must assess each powerplant separately and in
relation to other airplane systems and installations to show that a
failure of any powerplant system component or accessory will not--
(a) Prevent continued safe flight and landing;
(b) Cause serious injury that may be avoided; and
(c) Require immediate action by crewmembers for continued operation
of any remaining powerplant system.
Sec. 23.915 Automatic power control systems.
A power or thrust augmentation system that automatically controls
the power or thrust on the operating powerplant, must--
(a) Provide indication to the flightcrew when the system is
operating;
(b) Provide a means for the pilot to deactivate the automatic
function; and
(c) Prevent inadvertent deactivation.
Sec. 23.920 Reversing systems.
The airplane must be capable of continued safe flight and landing
under any available reversing system setting.
Sec. 23.925 Powerplant operational characteristics.
(a) The powerplant must operate at any negative acceleration that
may occur during normal and emergency operation, within the airplane
operating limitations.
(b) The pilot must have the capability to stop and restart the
powerplant in flight.
(c) The airplane must have an independent power source for
restarting each powerplant following an in-flight shutdown.
Sec. 23.930 Fuel system
(a) Each fuel system must--
(1) Provide an independent fuel supply to each powerplant in at
least one configuration;
(2) Avoid ignition from unplanned sources;
(3) Provide the fuel required to achieve maximum power or thrust
plus a margin for likely variables, in all temperature and altitude
conditions within the airplane operating envelope;
(4) Provide a means to remove the fuel from the airplane;
(5) Be capable of retaining fuel when subject to inertia loads
under expected operating conditions; and
(6) Prevent hazardous contamination of the fuel supply.
(b) Each fuel storage system must--
(1) Withstand the loads and pressures under expected operating
conditions;
(2) Provide a means to prevent loss of fuel during any maneuver
under operating conditions for which certification is requested;
(3) Prevent discharge when transferring fuel;
(4) Provide fuel for at least one-half hour of operation at maximum
continuous power or thrust; and
(5) Be capable of jettisoning fuel if required for landing.
(c) If a pressure refueling system is installed, it must have a
means to--
(1) Prevent the escape of hazardous quantities of fuel;
(2) Automatically shut-off before exceeding the maximum fuel
quantity of the airplane; and
(3) Provide an indication of a failure at the fueling station.
Sec. 23.935 Powerplant induction and exhaust systems.
The air induction system for each power unit and its accessories
must--
(a) Supply the air required by that power unit and its accessories
under expected operating conditions; and
(b) Provide a means to discharge potential harmful material.
Sec. 23.940 Powerplant ice protection.
(a) The airplane design must prevent foreseeable accumulation of
ice or snow that adversely affects powerplant operation.
(b) The powerplant design must prevent any accumulation of ice or
snow that adversely affects powerplant operation, in those icing
conditions for which certification is requested.
Sec. 23.1000 Powerplant fire protection.
(a) A powerplant may only be installed in a designated fire zone.
(b) Each component, line, and fitting carrying flammable fluids,
gases, or air subject to fire conditions must be fire resistant, except
components storing concentrated flammable material must be fireproof or
enclosed by a fireproof shield.
(c) The applicant must provide a means to shut off fuel or
flammable material for each powerplant that must--
(1) Not restrict fuel to remaining units; and
(2) Prevent inadvertent operation.
(d) For levels 3 and 4 airplanes with a powerplant located outside
the pilot's view that uses combustible fuel, the applicant must install
a fire extinguishing system.
(e) For levels 3 and 4 airplanes, the applicant must install a fire
detection system in each designated fire zone.
(f) Each fire detection system must provide a means to alert the
flightcrew in the event of a detection of fire or failure of the
system.
(g) There must be a means to check the fire detection system in
flight.
Subpart F--Equipment
Sec. 23.1300 Airplane level systems requirements.
(a) The equipment and systems required for an airplane to operate
safely in the kinds of operations for which certification is requested
(Day VFR, Night VFR, IFR) must be designed and installed to--
(1) Meet the level of safety applicable to the certification and
performance level of the airplane; and
(2) Perform their intended function throughout the operating and
environmental limits specified by the applicant.
(b) Non[hyphen]required airplane equipment and systems, considered
separately and in relation to other systems, must be designed and
installed so their operation or failure does not have an adverse effect
on the airplane or its occupants.
Sec. 23.1305 Function and installation.
(a) Each item of installed equipment must--
(1) Perform its intended function;
(2) Be installed according to limitations specified for that
equipment; and
(3) Be labeled, if applicable, as to its identification, function
or operating limitations, or any combination of these factors.
(b) There must be a discernable means of providing system operating
parameters required to operate the airplane, including warnings,
cautions, and normal indications to the responsible crewmember.
(c) Information concerning an unsafe system operating condition
must be provided in a timely manner to the crewmember responsible for
taking corrective action. Presentation of this information must be
clear enough to avoid likely crewmember errors.
Sec. 23.1310 Flight, navigation, and powerplant instruments.
(a) Installed systems must provide the flightcrew member who sets
or monitors flight parameters for the flight, navigation, and
powerplant the information necessary to do so during each phase of
flight. This information must include--
[[Page 13524]]
(1) Parameters and trends, as needed for normal, abnormal, and
emergency operation; and
(2) Limitations, unless the applicant shows each limitation will
not be exceeded in all intended operations.
(b) Indication systems that integrate the display of flight or
powerplant parameters to operate the airplane or are required by the
operating rules of this chapter must--
(1) Not inhibit the primary display of flight or powerplant
parameters needed by any flightcrew member in any normal mode of
operation; and
(2) In combination with other systems, be designed and installed so
information essential for continued safe flight and landing will be
available to the flightcrew in a timely manner after any single failure
or probable combination of failures.
Sec. 23.1315 Equipment, systems, and installations.
For any airplane system or equipment whose failure or abnormal
operation has not been specifically addressed by another requirement in
this part, the applicant must:
(a) Examine the design and installation of airplane systems and
equipment, separately and in relation to other airplane systems and
equipment to determine--
(1) If a failure would prevent continued safe flight and landing;
and
(2) If any other failure would significantly reduce the capability
of the airplane or the ability of the flightcrew to cope with adverse
operating conditions.
(b) Design and install each system and equipment, examined
separately and in relation to other airplane systems and equipment,
such that--
(1) Each catastrophic failure condition is extremely improbable;
(2) Each hazardous failure condition is extremely remote; and
(3) Each major failure condition is remote.
Sec. 23.1320 Electrical and electronic system lightning protection.
For an airplane approved for IFR operations:
(a) Each electrical or electronic system that performs a function,
the failure of which would prevent the continued safe flight and
landing of the airplane, must be designed and installed such that--
(1) The airplane system level function continues to perform during
and after the time the airplane is exposed to lightning; and
(2) The system automatically recovers normal operation of that
function in a timely manner after the airplane is exposed to lightning
unless the system's recovery conflicts with other operational or
functional requirements of the system.
(b) Each electrical and electronic system that performs a function,
the failure of which would reduce the capability of the airplane or the
ability of the flightcrew to respond to an adverse operating condition,
must be designed and installed such that the function recovers normal
operation in a timely manner after the airplane is exposed to
lightning.
Sec. 23.1325 High-intensity Radiated Fields (HIRF) protection.
(a) Electrical and electronic systems that perform a function, the
failure of which would prevent the continued safe flight and landing of
the airplane, must be designed and installed such that--
(1) The airplane system level function is not adversely affected
during and after the time the airplane is exposed to the HIRF
environment; and
(2) The system automatically recovers normal operation of that
function in a timely manner after the airplane is exposed to the HIRF
environment, unless the system's recovery conflicts with other
operational or functional requirements of the system.
(b) For airplanes approved for IFR operations, the applicant must
design and install each electrical and electronic system that performs
a function, the failure of which would reduce the capability of the
airplane or the ability of the flightcrew to respond to an adverse
operating condition, so the function recovers normal operation in a
timely manner after the airplane is exposed to the HIRF environment.
Sec. 23.1330 System power generation, storage, and distribution.
The power generation, storage, and distribution for any system must
be designed and installed to--
(a) Supply the power required for operation of connected loads
during all likely operating conditions;
(b) Ensure no single failure or malfunction will prevent the system
from supplying the essential loads required for continued safe flight
and landing; and
(c) Have enough capacity, if the primary source fails, to supply
essential loads, including non-continuous essential loads for the time
needed to complete the function, for--
(1) At least 30 minutes for airplanes certificated with a maximum
altitude of 25,000 feet (7,620 meters) or less; and
(2) At least 60 minutes for airplanes certificated with a maximum
altitude over 25,000 feet (7,620 meters).
Sec. 23.1335 External and cockpit lighting.
(a) The applicant must design and install all lights to prevent
adverse effects on the performance of flightcrew duties.
(b) Any position and anti-collision lights, if required by part 91
of this chapter, must have the intensities, flash rate, colors, fields
of coverage, and other characteristics to provide sufficient time for
another aircraft to avoid a collision.
(c) Any position lights, if required by part 91 of this chapter,
must include a red light on the left side of the airplane, a green
light on the right side of the airplane, spaced laterally as far apart
as space allows, and a white light facing aft, located on an aft
portion of the airplane or on the wing tips.
(d) The applicant must design and install taxi and landing lights
so they provide sufficient light for night operations.
(e) For seaplanes or amphibian airplanes, riding lights must
provide a white light visible in clear atmospheric conditions.
Sec. 23.1400 Safety equipment.
Safety and survival equipment, required by the operating rules of
this chapter, must be reliable, readily accessible, easily
identifiable, and clearly marked to identify its method of operation.
Sec. 23.1405 Flight in icing conditions.
(a) If an applicant requests certification for flight in icing
conditions, the applicant must demonstrate that--
(1) The ice protection system provides for safe operation; and
(2) The airplane is protected from stalling when the autopilot is
operating in a vertical mode.
(b) The demonstration specified in paragraph (a) of this section,
must be conducted in atmospheric icing conditions specified in part 1
of appendix C to part 25 of this chapter, and any additional icing
conditions for which certification is requested.
Sec. 23.1410 Pressurized systems elements.
(a) The minimum burst pressure of hydraulic systems must be at
least 2.5 times the design operating pressure. The proof pressure must
be at least 1.5 times the maximum operating pressure.
(b) On multiengine airplanes, engine driven accessories essential
to safe operation must be distributed among multiple engines.
(c) The minimum burst pressure of cabin pressurization system
elements must be at least 2.0 times, and proof pressure must be at
least 1.5 times, the maximum normal operating pressure.
[[Page 13525]]
(d) The minimum burst pressure of pneumatic system elements must be
at least 3.0 times, and proof pressure must be at least 1.5 times, the
maximum normal operating pressure.
(e) Other pressurized system elements must have pressure margins
that take into account system design and operating conditions.
Sec. 23.1457 Cockpit voice recorders.
(a) Each cockpit voice recorder required by the operating rules of
this chapter must be approved and must be installed so that it will
record the following:
(1) Voice communications transmitted from or received in the
airplane by radio.
(2) Voice communications of flightcrew members on the flight deck.
(3) Voice communications of flightcrew members on the flight deck,
using the airplane's interphone system.
(4) Voice or audio signals identifying navigation or approach aids
introduced into a headset or speaker.
(5) Voice communications of flightcrew members using the passenger
loudspeaker system, if there is such a system and if the fourth channel
is available in accordance with the requirements of paragraph
(c)(4)(ii) of this section.
(6) If datalink communication equipment is installed, all datalink
communications, using an approved data message set. Datalink messages
must be recorded as the output signal from the communications unit that
translates the signal into usable data.
(b) The recording requirements of paragraph (a)(2) of this section
must be met by installing a cockpit-mounted area microphone, located in
the best position for recording voice communications originating at the
first and second pilot stations and voice communications of other
crewmembers on the flight deck when directed to those stations. The
microphone must be so located and, if necessary, the preamplifiers and
filters of the recorder must be so adjusted or supplemented, so that
the intelligibility of the recorded communications is as high as
practicable when recorded under flight cockpit noise conditions and
played back. Repeated aural or visual playback of the record may be
used in evaluating intelligibility.
(c) Each cockpit voice recorder must be installed so that the part
of the communication or audio signals specified in paragraph (a) of
this section obtained from each of the following sources is recorded on
a separate channel:
(1) For the first channel, from each boom, mask, or handheld
microphone, headset, or speaker used at the first pilot station.
(2) For the second channel from each boom, mask, or handheld
microphone, headset, or speaker used at the second pilot station.
(3) For the third channel--from the cockpit-mounted area
microphone.
(4) For the fourth channel from:
(i) Each boom, mask, or handheld microphone, headset, or speaker
used at the station for the third and fourth crewmembers.
(ii) If the stations specified in paragraph (c)(4)(i) of this
section are not required or if the signal at such a station is picked
up by another channel, each microphone on the flight deck that is used
with the passenger loudspeaker system, if its signals are not picked up
by another channel.
(5) And that as far as is practicable all sounds received by the
microphone listed in paragraphs (c)(1), (2), and (4) of this section
must be recorded without interruption irrespective of the position of
the interphone-transmitter key switch. The design shall ensure that
sidetone for the flightcrew is produced only when the interphone,
public address system, or radio transmitters are in use.
(d) Each cockpit voice recorder must be installed so that:
(1) (i) It receives its electrical power from the bus that provides
the maximum reliability for operation of the cockpit voice recorder
without jeopardizing service to essential or emergency loads.
(ii) It remains powered for as long as possible without
jeopardizing emergency operation of the airplane.
(2) There is an automatic means to simultaneously stop the recorder
and prevent each erasure feature from functioning, within 10 minutes
after crash impact.
(3) There is an aural or visual means for preflight checking of the
recorder for proper operation.
(4) Any single electrical failure external to the recorder does not
disable both the cockpit voice recorder and the flight data recorder.
(5) It has an independent power source--
(i) That provides 101 minutes of electrical power to
operate both the cockpit voice recorder and cockpit-mounted area
microphone;
(ii) That is located as close as practicable to the cockpit voice
recorder; and
(iii) To which the cockpit voice recorder and cockpit-mounted area
microphone are switched automatically in the event that all other power
to the cockpit voice recorder is interrupted either by normal shutdown
or by any other loss of power to the electrical power bus.
(6) It is in a separate container from the flight data recorder
when both are required. If used to comply with only the cockpit voice
recorder requirements, a combination unit may be installed.
(e) The recorder container must be located and mounted to minimize
the probability of rupture of the container as a result of crash impact
and consequent heat damage to the recorder from fire.
(1) Except as provided in paragraph (e)(2) of this section, the
recorder container must be located as far aft as practicable, but need
not be outside of the pressurized compartment, and may not be located
where aft-mounted engines may crush the container during impact.
(2) If two separate combination digital flight data recorder and
cockpit voice recorder units are installed instead of one cockpit voice
recorder and one digital flight data recorder, the combination unit
that is installed to comply with the cockpit voice recorder
requirements may be located near the cockpit.
(f) If the cockpit voice recorder has a bulk erasure device, the
installation must be designed to minimize the probability of
inadvertent operation and actuation of the device during crash impact.
(g) Each recorder container must--
(1) Be either bright orange or bright yellow;
(2) Have reflective tape affixed to its external surface to
facilitate its location under water; and
(3) Have an underwater locating device, when required by the
operating rules of this chapter, on or adjacent to the container, which
is secured in such manner that they are not likely to be separated
during crash impact.
Sec. 23.1459 Flight data recorders.
(a) Each flight recorder required by the operating rules of this
chapter must be installed so that--
(1) It is supplied with airspeed, altitude, and directional data
obtained from sources that meet the aircraft level system requirements
of Sec. 23.1300 and the functionality specified in Sec. 23.1305;
(2) The vertical acceleration sensor is rigidly attached, and
located longitudinally either within the approved center of gravity
limits of the airplane, or at a distance forward or aft of these limits
that does not exceed 25 percent of the airplane's mean aerodynamic
chord;
(3)(i) It receives its electrical power from the bus that provides
the
[[Page 13526]]
maximum reliability for operation of the flight data recorder without
jeopardizing service to essential or emergency loads;
(ii) It remains powered for as long as possible without
jeopardizing emergency operation of the airplane;
(4) There is an aural or visual means for preflight checking of the
recorder for proper recording of data in the storage medium;
(5) Except for recorders powered solely by the engine-driven
electrical generator system, there is an automatic means to
simultaneously stop a recorder that has a data erasure feature and
prevent each erasure feature from functioning, within 10 minutes after
crash impact;
(6) Any single electrical failure external to the recorder does not
disable both the cockpit voice recorder and the flight data recorder;
and
(7) It is in a separate container from the cockpit voice recorder
when both are required. If used to comply with only the flight data
recorder requirements, a combination unit may be installed. If a
combination unit is installed as a cockpit voice recorder to comply
with Sec. 23.1457(e)(2), a combination unit must be used to comply
with this flight data recorder requirement.
(b) Each non-ejectable record container must be located and mounted
so as to minimize the probability of container rupture resulting from
crash impact and subsequent damage to the record from fire. In meeting
this requirement, the record container must be located as far aft as
practicable, but need not be aft of the pressurized compartment, and
may not be where aft-mounted engines may crush the container upon
impact.
(c) A correlation must be established between the flight recorder
readings of airspeed, altitude, and heading and the corresponding
readings (taking into account correction factors) of the first pilot's
instruments. The correlation must cover the airspeed range over which
the airplane is to be operated, the range of altitude to which the
airplane is limited, and 360 degrees of heading. Correlation may be
established on the ground as appropriate.
(d) Each recorder container must--
(1) Be either bright orange or bright yellow;
(2) Have reflective tape affixed to its external surface to
facilitate its location under water; and
(3) Have an underwater locating device, when required by the
operating rules of this chapter, on or adjacent to the container, which
is secured in such a manner that they are not likely to be separated
during crash impact.
(e) Any novel or unique design or operational characteristics of
the aircraft shall be evaluated to determine if any dedicated
parameters must be recorded on flight recorders in addition to or in
place of existing requirements.
Subpart G--Flightcrew Interface and Other Information
Sec. 23.1500 Flightcrew interface.
(a) The pilot compartment and its equipment must allow each pilot
to perform his or her duties, including taxi, takeoff, climb, cruise,
descent, approach, landing, and perform any maneuvers within the
operating envelope of the airplane, without excessive concentration,
skill, alertness, or fatigue.
(b) The applicant must install flight, navigation, surveillance,
and powerplant controls and displays so qualified flightcrew can
monitor and perform all tasks associated with the intended functions of
systems and equipment. The system and equipment design must make the
possibility that a flightcrew error could result in a catastrophic
event highly unlikely.
Sec. 23.1505 Instrument markings, control markings, and placards.
(a) Each airplane must display in a conspicuous manner any placard
and instrument marking necessary for operation.
(b) The applicant must clearly mark each cockpit control, other
than primary flight controls, as to its function and method of
operation.
(c) The applicant must include instrument marking and placard
information in the Airplane Flight Manual.
Sec. 23.1510 Airplane flight manual.
The applicant must provide an Airplane Flight Manual that must be
delivered with each airplane that contains the following information--
(a) Operating limitations and procedures;
(b) Performance information;
(c) Loading information; and
(d) Any other information necessary for the operation of the
airplane.
Sec. 23.1515 Instructions for continued airworthiness.
The applicant must prepare Instructions for Continued
Airworthiness, in accordance with appendix A of this part, that are
acceptable to the Administrator prior to the delivery of the first
airplane or issuance of a standard certification of airworthiness,
whichever occurs later.
Appendix A to Part 23--Instructions for Continued Airworthiness
A23.1 General
(a) This appendix specifies requirements for the preparation of
Instructions for Continued Airworthiness as required by this part.
(b) The Instructions for Continued Airworthiness for each airplane
must include the Instructions for Continued Airworthiness for each
engine and propeller (hereinafter designated ``products''), for each
appliance required by this chapter, and any required information
relating to the interface of those appliances and products with the
airplane. If Instructions for Continued Airworthiness are not supplied
by the manufacturer of an appliance or product installed in the
airplane, the Instructions for Continued Airworthiness for the airplane
must include the information essential to the continued airworthiness
of the airplane.
(c) The applicant must submit to the FAA a program to show how
changes to the Instructions for Continued Airworthiness made by the
applicant or by the manufacturers of products and appliances installed
in the airplane will be distributed.
A23.2 Format
(a) The Instructions for Continued Airworthiness must be in the
form of a manual or manuals as appropriate for the quantity of data to
be provided.
(b) The format of the manual or manuals must provide for a
practical arrangement.
A23.3 Content
The contents of the manual or manuals must be prepared in the
English language. The Instructions for Continued Airworthiness must
contain the following manuals or sections and information:
(a) Airplane maintenance manual or section.
(1) Introduction information that includes an explanation of the
airplane's features and data to the extent necessary for maintenance or
preventive maintenance.
(2) A description of the airplane and its systems and installations
including its engines, propellers, and appliances.
(3) Basic control and operation information describing how the
airplane components and systems are controlled and how they operate,
including any special procedures and limitations that apply.
(4) Servicing information that covers details regarding servicing
points, capacities of tanks, reservoirs, types of fluids to be used,
pressures applicable
[[Page 13527]]
to the various systems, location of access panels for inspection and
servicing, locations of lubrication points, lubricants to be used,
equipment required for servicing, tow instructions and limitations,
mooring, jacking, and leveling information.
(b) Maintenance Instructions
(1) Scheduling information for each part of the airplane and its
engines, auxiliary power units, propellers, accessories, instruments,
and equipment that provides the recommended periods at which they
should be cleaned, inspected, adjusted, tested, and lubricated, and the
degree of inspection, the applicable wear tolerances, and work
recommended at these periods. However, the applicant may refer to an
accessory, instrument, or equipment manufacturer as the source of this
information if the applicant shows that the item has an exceptionally
high degree of complexity requiring specialized maintenance techniques,
test equipment, or expertise. The recommended overhaul periods and
necessary cross reference to the Airworthiness Limitations section of
the manual must also be included. In addition, the applicant must
include an inspection program that includes the frequency and extent of
the inspections necessary to provide for the continued airworthiness of
the airplane.
(2) Troubleshooting information describing probable malfunctions,
how to recognize those malfunctions, and the remedial action for those
malfunctions.
(3) Information describing the order and method of removing and
replacing products and parts with any necessary precautions to be
taken.
(4) Other general procedural instructions including procedures for
system testing during ground running, symmetry checks, weighing and
determining the center of gravity, lifting and shoring, and storage
limitations.
(c) Diagrams of structural access plates and information needed to
gain access for inspections when access plates are not provided.
(d) Details for the application of special inspection techniques
including radiographic and ultrasonic testing where such processes are
specified by the applicant.
(e) Information needed to apply protective treatments to the
structure after inspection.
(f) All data relative to structural fasteners such as
identification, discard recommendations, and torque values.
(g) A list of special tools needed.
(h) In addition, for level 4 airplanes, the following information
must be furnished--
(1) Electrical loads applicable to the various systems;
(2) Methods of balancing control surfaces;
(3) Identification of primary and secondary structures; and
(4) Special repair methods applicable to the airplane.
A23.4 Airworthiness limitations section
The Instructions for Continued Airworthiness must contain a section
titled Airworthiness Limitations that is segregated and clearly
distinguishable from the rest of the document. This section must set
forth each mandatory replacement time, structural inspection interval,
and related structural inspection procedure required for type
certification. If the Instructions for Continued Airworthiness consist
of multiple documents, the section required by this paragraph must be
included in the principal manual. This section must contain a legible
statement in a prominent location that reads ``The Airworthiness
Limitations section is FAA approved and specifies maintenance required
under Sec. Sec. 43.16 and 91.403 of Title 14 of the Code of Federal
Regulations unless an alternative program has been FAA approved.''
PART 35--AIRWORTHINESS STANDARDS: PROPELLERS
0
9. The authority citation for part 35 is revised to read as follows:
Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704.
0
10. In Sec. 35.1, revise paragraph (c) to read as follows:
Sec. 35.1 Applicability.
* * * * *
(c) An applicant is eligible for a propeller type certificate and
changes to those certificates after demonstrating compliance with
subparts A, B, and C of this part. However, the propeller may not be
installed on an airplane unless the applicant has shown compliance with
either Sec. 23.905(c) or Sec. 25.907 of this chapter, as applicable,
or compliance is not required for installation on that airplane.
* * * * *
0
11. In Sec. 35.37, revise paragraph (c)(1) to read as follows:
Sec. 35.37 Fatigue limits and evaluation.
* * * * *
(c) * * *
(1) The intended airplane by complying with Sec. 23.905(c) or
Sec. 25.907 of this chapter, as applicable; or
* * * * *
PART 43--MAINTENANCE, PREVENTIVE MAINTENANCE, REBUILDING, AND
ALTERATION
0
12. The authority citation for part 43 is revised to read as follows:
Authority: 42 U.S.C. 7572; 49 U.S.C. 106(f), 106(g), 40105,
40113, 44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.
0
13. In part 43, appendix E, revise the introductory text and paragraph
(a)(2) to read as follows:
Appendix E to Part 43--Altimeter System Test and Inspection
Each person performing the altimeter system tests and inspections
required by Sec. 91.411 must comply with the following:
(a) * * *
(2) Perform a proof test to demonstrate the integrity of the static
pressure system in a manner acceptable to the Administrator. For
airplanes certificated under part 25 of this chapter, determine that
leakage is within the tolerances established by Sec. 25.1325.
* * * * *
PART 91--GENERAL OPERATING AND FLIGHT RULES
0
14. The authority citation for part 91 continues to read as follows:
Authority: 49 U.S.C. 106(f), 106(g), 1155, 40101, 40103, 40105,
40113, 40120, 44101, 44111, 44701, 44704, 44709, 44711, 44712,
44715, 44716, 44717, 44722, 46306, 46315, 46316, 46504, 46506-46507,
47122, 47508, 47528-47531, 47534, articles 12 and 29 of the
Convention on International Civil Aviation (61 Stat. 1180), (126
Stat. 11).
0
15. In Sec. 91.205, revise paragraphs (b)(13) and (b)(14), and remove
paragraph (b)(16) to read as follows:
Sec. 91.205 Powered civil aircraft with standard category U.S.
airworthiness certificates: Instrument and equipment requirements.
* * * * *
(b) * * *
(13) An approved safety belt with an approved metal-to-metal
latching device, or other approved restraint system for each occupant 2
years of age or older.
(14) For small civil airplanes manufactured after July 18, 1978, an
approved shoulder harness or restraint system for each front seat. For
small civil airplanes manufactured after December 12, 1986, an approved
shoulder harness or restraint system for all seats. Shoulder harnesses
installed at flightcrew stations must permit the flightcrew member,
when seated and with the safety belt and shoulder harness fastened, to
perform all
[[Page 13528]]
functions necessary for flight operations. For purposes of this
paragraph--
(i) The date of manufacture of an airplane is the date the
inspection acceptance records reflect that the airplane is complete and
meets the FAA-approved type design data; and
(ii) A front seat is a seat located at a flightcrew member station
or any seat located alongside such a seat.
* * * * *
0
16. In Sec. 91.313, revise paragraph (g) introductory text to read as
follows:
Sec. 91.313 Restricted category civil aircraft: Operating
limitations.
* * * * *
(g) No person may operate a small restricted-category civil
airplane manufactured after July 18, 1978, unless an approved shoulder
harness or restraint system is installed for each front seat. The
shoulder harness or restraint system installation at each flightcrew
station must permit the flightcrew member, when seated and with the
safety belt and shoulder harness fastened or the restraint system
engaged, to perform all functions necessary for flight operation. For
purposes of this paragraph--
* * * * *
0
17. In Sec. 91.323, revise paragraph (b)(3) to read as follows:
Sec. 91.323 Increased maximum certificated weights for certain
airplanes operated in Alaska.
* * * * *
(b) * * *
(3) The weight at which the airplane meets the positive maneuvering
load factor n, where n = 2.1 + (24,000/(W + 10,000)) and W = design
maximum takeoff weight, except that n need not be more than 3.8; or
* * * * *
0
18. In Sec. 91.531, revise paragraphs (a)(1) and (a)(3) to read as
follows:
Sec. 91.531 Second in command requirements.
(a) * * *
(1) A large airplane or normal category level 4 airplane, except
that a person may operate an airplane certificated under SFAR 41
without a pilot who is designated as second in command if that airplane
is certificated for operation with one pilot.
* * *
(3) A commuter category airplane or normal category level 3
airplane, except that a person may operate those airplanes
notwithstanding paragraph (a)(1) of this section, that have a passenger
seating configuration, excluding pilot seats, of nine or less without a
pilot who is designated as second in command if that airplane is type
certificated for operations with one pilot.
* * * * *
PART 121--OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL
OPERATIONS
0
19. The authority citation for part 121 continues to read as follows:
Authority: 49 U.S.C. 106(f), 106(g), 40103, 40113, 40119, 41706,
42301 preceding note added by Pub. L. 112-95, Sec. 412, 126 Stat.
89, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-44717,
44722, 44729, 44732; 46105; Pub. L. 111-216, 124 Stat. 2348 (49
U.S.C. 44701 note); Pub. L. 112-95, 126 Stat. 62 (49 U.S.C. 44732
note).
0
20. In Sec. 121.310, revise paragraph (b)(2)(iii) to read as follows:
Sec. 121.310 Additional emergency equipment.
* * * * *
(b) * * *
(2) * * *
(iii) For a nontransport category turbopropeller powered airplane
type certificated after December 31, 1964, each passenger emergency
exit marking and each locating sign must be manufactured to meet the
requirements of Sec. 23.811(b) of this chapter in effect on June 16,
1994. On these airplanes, no sign may continue to be used if its
luminescence (brightness) decreases to below 100 microlamberts.
* * * * *
PART 135--OPERATING REQUIREMENTS: COMMUTER AND ON DEMAND OPERATIONS
AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT
0
21. The authority citation for part 135 continues to read as follows:
Authority: 49 U.S.C. 106(f), 106(g), 41706, 40113, 44701-44702,
44705, 44709, 44711-44713, 44715-44717, 44722, 44730, 45101-45105;
Pub. L. 112-95, 126 Stat. 58 (49 U.S.C. 44730).
0
22. In Sec. 135.169, revise paragraphs (b) introductory text, (b)(6),
and (b)(7), and add paragraph (b)(8) to read as follows:
Sec. 135.169 Additional airworthiness requirements.
* * * * *
(b) No person may operate a small airplane that has a passenger
seating configuration, excluding pilot seats, of 10 seats or more
unless it is type certificated--
* * * * *
(6) In the normal category and complies with section 1.(b) of
Special Federal Aviation Regulation No. 41;
(7) In the commuter category; or
(8) In the normal category, using a means of compliance accepted by
the Administrator equivalent to the airworthiness standards applicable
to the certification of airplanes in the commuter category found in
part 23 of this chapter through amendment 23-62, effective January 31,
2012.
* * * * *
Issued under authority provided by 49 U.S.C. 106(f), 44701(a),
44703 and Pub. L. 113-53 (127 Stat. 584; 49 U.S.C. 44704 note) in
Washington, DC, on March 7, 2016.
Dorenda D. Baker,
Director, Aircraft Certification Service.
[FR Doc. 2016-05493 Filed 3-9-16; 11:15 am]
BILLING CODE 4910-13-P