[Federal Register Volume 78, Number 16 (Thursday, January 24, 2013)]
[Proposed Rules]
[Pages 5148-5149]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-01379]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2012-1332; Notice No. 25-12-19-SC]
Special Conditions: Embraer S.A., Model EMB-550 Airplanes; Flight
Envelope Protection: General Limiting Requirements
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
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SUMMARY: This action proposes special conditions for the Embraer S.A.
Model EMB-550 airplane. This airplane will have a novel or unusual
design feature(s), specifically new control architecture and a full
digital flight control system which provides flight envelope
protections. The applicable airworthiness regulations do not contain
adequate or appropriate safety standards for this design feature. These
proposed special conditions contain the additional safety standards
that the Administrator considers necessary to establish a level of
safety equivalent to that established by the existing airworthiness
standards.
DATES: Send your comments on or before March 11, 2013.
ADDRESSES: Send comments identified by docket number FAA-2012-1332
using any of the following methods:
Federal eRegulations 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 8 a.m. and 5 p.m.,
Monday through Friday, except federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: The FAA will post all comments it receives, without
change, to http://www.regulations.gov/, including any personal
information the commenter provides. Using the search function of the
docket web site, anyone can find and read the electronic form of all
comments received into any FAA docket, including the name of the
individual sending the comment (or signing the comment for an
association, business, labor union, etc.). DOT's complete Privacy Act
Statement can be found in the Federal Register published on April 11,
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov/.
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: Joe Jacobsen, FAA, Airplane and Flight
Crew Interface Branch, ANM-111, Transport Airplane Directorate,
Aircraft Certification Service, 1601 Lind Avenue SW., Renton,
Washington 98057-3356; telephone 425-227-2011; facsimile 425-227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data.
We will consider all comments we receive on or before the closing
date for comments. We may change these special conditions based on the
comments we receive.
Background
On May 14, 2009, Embraer S.A. applied for a type certificate for
their new Model EMB-550 airplane. The Model EMB-550 airplane is the
first of a new family of jet airplanes designed for corporate flight,
fractional, charter, and private owner operations. The aircraft has a
conventional configuration with low wing and T-tail empennage. The
primary structure is metal with composite empennage and control
surfaces. The Model EMB-550 airplane is designed for 8 passengers, with
a maximum of 12 passengers. It is equipped with two Honeywell HTF7500-E
medium bypass ratio turbofan engines mounted on aft fuselage pylons.
Each engine produces approximately 6,540 pounds of thrust for normal
takeoff. The primary flight controls consist of hydraulically powered
fly-by-wire elevators, aileron and rudder, controlled by the pilot or
copilot sidestick.
Embraer S.A. has developed comprehensive flight envelope protection
features integral to the electronic flight control system design. These
flight envelope protection features include limitations on angle-of-
attack, normal load factor, bank angle, pitch angle, and speed. To
accomplish this flight-envelope-limiting, a significant change (or
multiple changes) occurs in the control laws of the electronic flight
control system as the limit is approached or exceeded. When failure
states occur in the electronic flight control system, flight envelope
protection features can likewise either be modified, or in some cases,
eliminated. The current regulations were not written with these
comprehensive flight-envelope-limiting systems in mind.
Type Certification Basis
Under the provisions of Title 14, Code of Federal Regulations (14
CFR) 21.17, Embraer S.A. must show that the Model EMB-550 airplane
meets the applicable provisions of part 25, as amended by Amendments
25-1 through 25-127 thereto.
If the Administrator finds that the applicable airworthiness
regulations (i.e., 14 CFR part 25) do not contain adequate or
appropriate safety standards for the Model EMB-550 airplane because of
a novel or unusual design feature, special conditions are prescribed
under the provisions of Sec. 21.16.
Special conditions are initially applicable to the model for which
they are issued. Should the type certificate for that model be amended
later to
[[Page 5149]]
include any other model that incorporates the same or similar novel or
unusual design feature, the special conditions would also apply to the
other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the Model EMB-550 airplane must comply with the fuel vent
and exhaust emission requirements of 14 CFR part 34 and the noise
certification requirements of 14 CFR part 36 and the FAA must issue a
finding of regulatory adequacy under Sec. 611 of Public Law 92-574,
the ``Noise Control Act of 1972.''
The FAA issues special conditions, as defined in 14 CFR 11.19, in
accordance with Sec. 11.38, and they become part of the type-
certification basis under Sec. 21.17(a)(2).
Novel or Unusual Design Features
The Model EMB-550 airplane will incorporate the following novel or
unusual design features: New control architecture and a full digital
flight control system which provides comprehensive flight envelope
protections.
Discussion
The applicable airworthiness regulation in this instance is 14 CFR
25.143. The purpose of Sec. 25.143 is to verify that any operational
maneuvers conducted within the operational envelope can be accomplished
smoothly with average piloting skill and without exceeding any
structural limits. The pilot should be able to predict the airplane
response to any control input. During the course of the flight test
program, the pilot determines compliance with Sec. 25.143 through
primarily qualitative methods. During flight test, the pilot should
evaluate all of the following:
The interface between each protection function,
Transitions from one mode to another,
The aircraft response to intentional dynamic maneuvering,
whenever applicable, through dedicated maneuvers,
General controllability assessment,
High speed characteristics, and
High angle-of-attack.
Section Sec. 25.143, however, does not adequately ensure that the
novel or unusual features of the Model EMB-550 airplane will have a
level of safety equivalent to that of existing standards. This special
condition is therefore required to accommodate the the flight-envelope-
limiting systems in the Model EMB-550 airplane. The additional safety
standards in this special condition will ensure a level of safety
equivalent to that of existing standards.
Applicability
As discussed above, these special conditions are applicable to the
Model EMB-550 airplane. Should Embraer S.A. apply at a later date for a
change to the type certificate to include another model incorporating
the same novel or unusual design feature, the special conditions would
apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
on one model of airplanes. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701, 44702, 44704.
The Proposed Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes the
following special conditions as part of the type certification basis
for Embraer S.A. Model EMB-550 airplanes.
1. General Limiting Requirements:
a. Onset characteristics of each envelope protection feature must
be smooth, appropriate to the phase of flight and type of maneuver, and
not in conflict with the ability of the pilot to satisfactorily change
airplane flight path, speed, or attitude as needed.
b. Limit values of protected flight parameters (and if applicable,
associated warning thresholds) must be compatible with the following:
i. Airplane structural limits,
ii. Required safe and controllable maneuvering of the airplane, and
iii. Margins to critical conditions. Unsafe flight characteristics/
conditions must not result if dynamic maneuvering, airframe and system
tolerances (both manufacturing and in-service), and non-steady
atmospheric conditions, in any appropriate combination and phase of
flight, can produce a limited flight parameter beyond the nominal
design limit value.
c. The airplane must be responsive to intentional dynamic
maneuvering to within a suitable range of the parameter limit. Dynamic
characteristics such as damping and overshoot must also be appropriate
for the flight maneuver and limit parameter in question.
d. When simultaneous envelope limiting is engaged, adverse coupling
or adverse priority must not result.
2. Failure States: Electronic flight control system failures
(including sensor) must not result in a condition where a parameter is
limited to such a reduced value that safe and controllable maneuvering
is no longer available. The crew must be alerted by suitable means if
any change in envelope limiting or maneuverability is produced by
single or multiple failures of the electronic flight control system not
shown to be extremely improbable.
Issued in Renton, Washington, on December 19, 2012.
K.C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2013-01379 Filed 1-23-13; 8:45 am]
BILLING CODE 4910-13-P