[Federal Register Volume 79, Number 9 (Tuesday, January 14, 2014)]
[Rules and Regulations]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-00451]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2013-0895; Notice No. 25-516-SC]
Special Conditions: Airbus, A350-900 Series Airplane; Design Roll
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions, request for comments.
SUMMARY: These special conditions are issued for Airbus Model A350-900
series airplanes. These airplanes will have a novel or unusual design
feature(s) associated with the airplane's response to the design roll
maneuver. The applicable airworthiness regulations do not contain
adequate or appropriate safety standards for this design feature. These
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: The effective date of these special conditions is January 14,
2014. We must receive your comments by February 28, 2014.
ADDRESSES: Send comments identified by docket number FAA-2013-0895
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: Todd Martin, FAA, Airframe and Cabin
Safety Branch, ANM-115, Transport Airplane Directorate, Aircraft
Certification Service, 1601 Lind Avenue SW., Renton, Washington, 98057-
3356; telephone (425) 227-1178; facsimile (425) 227-1320.
SUPPLEMENTARY INFORMATION: The substance of these special conditions
has been subject to the public comment process in several prior
instances with no substantive comments received. The FAA therefore
finds that good cause exists for making these special conditions
effective upon issuance.
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 by 45 days after
publication of these special condition in the Federal Register. 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 Airbus Model A350-900 series is equipped with an electronic
flight control system that provides control of the aircraft through
pilot inputs to the flight computer. Current part 25 airworthiness
regulations account for control laws for which aileron deflection is
proportional to control stick deflection. They do not address any
nonlinearities or other effects on aileron actuation that may be caused
by electronic flight controls. Since this type of system may affect
flight loads, and therefore the structural capability of the airplane,
specific regulations are needed to address these effects. These special
conditions adjust the current roll maneuver requirement, Title 14, Code
of Federal Regulations (14 CFR) 25.349(a), to take into account the
effects of an electronic flight control system.
Type Certification Basis
Under Sec. 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 25-129.
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 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 novel or
unusual design feature, the special conditions would also apply to the
In addition to the applicable airworthiness regulations and 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 Airbus Model A350-900 series will incorporate the following
novel or unusual design features: An electronic flight control system
that can affect how the airplane responds to a roll maneuver. This
requires that the roll maneuver result from defined movements of the
cockpit roll control as opposed to defined aileron deflections. This
also requires an additional load condition at VA, in which
the cockpit roll control is returned to neutral following the initial
These proposed special conditions differ from similar special
conditions applied on previous programs; and are limited to the roll
axis only, whereas previous special conditions also included the pitch
and yaw axes. Special conditions are no longer needed for the pitch or
yaw axes, because 14 CFR part 25 Amendment 25-91 takes into account the
effects of an electronic flight control system in those axes (Sec.
25.331 for pitch and Sec. 25.351 for yaw).
As discussed above, these 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 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
The substance of these special conditions has been subjected to the
notice and comment period in several prior instances and has been
derived without substantive change from those previously issued. It is
unlikely that prior public comment would result in a significant change
from the substance contained herein. Therefore, the FAA has determined
that prior public notice and comment are unnecessary and impracticable,
and good cause exists for adopting these special conditions upon
issuance. The FAA is requesting comments to allow interested persons to
submit views that may not have been submitted in response to the prior
opportunities for comment described above.
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 Special Conditions
Accordingly, pursuant to the authority delegated to me by the
Administrator, the following special conditions are issued as part of
the type certification basis for Airbus Model A350-900 series
1. Design Roll Maneuver Conditions
The following conditions, speeds, and cockpit roll control motions
(except as the motions may be limited by pilot effort) must be
considered in combination with an airplane load factor of zero and of
two-thirds of the positive maneuvering factor used in design. In
determining the resulting control surface deflections, the torsional
flexibility of the wing must be considered in accordance with Sec.
a. Conditions corresponding to steady rolling velocities must be
investigated. In addition, conditions corresponding to maximum angular
acceleration must be investigated for airplanes with engines or other
weight concentrations outboard of the fuselage. For the angular
acceleration conditions, zero rolling velocity may be assumed in the
absence of a rational time history investigation of the maneuver.
b. At VA, sudden movement of the cockpit roll control up
to the limit is assumed. The position of the cockpit roll control must
be maintained until a steady roll rate is achieved and then must be
returned suddenly to the neutral position.
c. At VC, the cockpit roll control must be moved
suddenly and maintained so as to achieve a roll rate not less than that
obtained in paragraph b.
d. At VD, the cockpit roll control must be moved
suddenly and maintained so as to achieve a roll rate not less than one-
third of that obtained in paragraph b.
Issued in Renton, Washington, on October 22, 2013.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
[FR Doc. 2014-00451 Filed 1-13-14; 8:45 am]
BILLING CODE 4910-13-P