[Federal Register Volume 79, Number 5 (Wednesday, January 8, 2014)]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-00100]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2013-0901; Notice No. 25-13-23-SC]
Special Conditions: Airbus, Model A350-900 Series Airplane;
Flight Envelope Protection: High Speed Limiting
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
SUMMARY: This action proposes special conditions for Airbus Model A350-
900 series airplanes. These airplanes will have a novel or unusual
design feature associated with high speed limiting. 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 February 7, 2014.
ADDRESSES: Send comments identified by docket number FAA-2013-0901
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 9 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
Flightcrew 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-
We invite interested people to take part in this rulemaking by
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.
On August 25, 2008, Airbus applied for a type certificate for their
new Model A350-900 series airplane. Later, Airbus requested and the FAA
approved an extension to the application for FAA type certification to
June 28, 2009. The Model A350-900 series has a conventional layout with
twin wing-mounted Rolls-Royce Trent engines. It features a twin aisle
9-abreast economy class layout, and accommodates side-by-side placement
of LD-3 containers in the cargo compartment. The basic Model A350-900
series configuration will accommodate 315 passengers in a standard two-
class arrangement. The design cruise speed is Mach 0.85 with a Maximum
Take-Off Weight of 602,000 lbs. Airbus proposes the Model A350-900
series to be certified for extended operations (ETOPS) beyond 180
minutes at entry into service for up to a 420-minute maximum diversion
The longitudinal control law design of the Airbus Model A350-900
incorporates an overspeed protection system in the normal mode; this
would prevent the pilot from inadvertently or intentionally exceeding a
speed approximately equivalent to VFC or attaining
VDF. Current Title 14 Code of Federal Regulations (14 CFR)
part 25 sections do not relate to a high speed limiting protection
system that might preclude or modify flying qualities assessments in
the overspeed region. However, the requirements of Sec. 25.253 (High-
speed characteristics) and its related policy are applicable to the
Model A350-900 series and not affected by this proposed special
Type Certification Basis
Under Title 14, Code of Federal Regulations (14 CFR) 21.17, Airbus
must show that the Model A350-900 series meets the applicable
provisions of 14 CFR part 25, as amended by Amendments 25-1 through 25-
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 Airbus Model A350-900 series
because of a novel or unusual design feature, special conditions are
prescribed under 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 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
proposed special conditions, the Model A350-900 series 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 section 611 of Public Law
92-574, the ``Noise Control Act of 1972.''
The FAA issues special conditions, as defined in 14 CFR 11.19,
under 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 A350-900 series will incorporate the following novel or
unusual design features: An overspeed protection system which prevents
the pilot from inadvertently or intentionally exceeding a speed
approximately equivalent to VFC or attaining VDF.
At VMO + 10 knots or MMO + 0.02, an automatic
nose up pitch is applied with phase advance in case of high
acceleration. The speed stabilizes at VD - 10kts/
MD - 0.02 if the stick is full forward, or the speed will
return below VMO/MMO if the stick is released.
This proposed special condition establishes requirements to ensure
that operation of the high speed limiting protection system does not
impede normal attainment of speeds up to the overspeed warning. Its
main features are:
1. It protects the airplane against high speed/high Mach number
flight conditions beyond VMO/MMO.
2. It does not interfere with flight at VMO/
MMO, even in turbulent air.
3. It still provides load factor limitation through the ``pitch
limiting'' function described below.
4. It restores positive static stability beyond VMO/
As discussed above, these proposed special conditions apply to
Airbus Model A350-900 series airplanes. Should Airbus apply later for a
change to the type certificate to include another model incorporating
the same novel or unusual design feature, the proposed special
conditions would apply to that model as well.
This action affects only certain novel or unusual design features
on the Airbus Model A350-900 series airplanes. It is not a rule of
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
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 condition as part of the type certification basis for
Airbus Model A350-900 series airplanes.
In addition to Sec. 25.143, the following requirements apply:
Operation of the high speed limiter during all routine and descent
procedure flight must not impede normal attainment of speeds up to
Issued in Renton, Washington, on October 22, 2013.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
[FR Doc. 2014-00100 Filed 1-7-14; 8:45 am]
BILLING CODE 4910-13-P