Document ID: FAA-2013-0903-0001
Agency: faa
Document Type: Proposed Rule
Title: Special Conditions: Airbus, Model A350-900 Series Airplane; Side Stick Controllers
Posted Date: 2013-11-08T05:00Z

[Federal Register Volume 78, Number 217 (Friday, November 8, 2013)]
[Proposed Rules]
[Pages 67077-67078]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-26912]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2013-0903; Notice No. 25-13-26-SC]

Special Conditions: Airbus, Model A350-900 Series Airplane; Side 
Stick Controllers

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for the Airbus Model 
A350-900 series airplanes. These airplanes will have a novel or unusual 
design feature(s) associated with side stick controllers for pitch and 
roll control instead of conventional wheels and columns. 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 December 23, 2013.

ADDRESSES: Send comments identified by docket number FAA-2013-0903 
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: Loran Haworth, FAA, Airplane and 
Flight Interface Branch, ANM-111, Transport Airplane Directorate, 
Aircraft Certification Service, 1601 Lind Avenue SW., Renton, 
Washington 98057-3356; telephone (425) 227-1133; facsimile (425) 227-
1320.

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 proposed special conditions 
based on the comments we receive.

Background

    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 XWB engines. It features a twin 
aisle 9-abreast economy class layout, and

[[Page 67078]]

accommodates side-by-side placement of LD-3 containers in the cargo 
compartment. The basic Airbus 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 time.
    The Airbus Model A350-900 series airplane, like its predecessors 
the A320, A330, A340 and A380, will use side stick controllers for 
pitch and roll control. Regulatory requirements pertaining to 
conventional wheel and column, such as pilot strength and 
controllability, are not directly applicable for the side stick. In 
addition, pilot control authority may be uncertain because the side 
sticks are not mechanically interconnected as with conventional wheel 
and column controls.

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-
128.
    The FAA has determined that Airbus Model A350-900 series airplanes 
must comply with the following sections: Sec. Sec.  25.143, 25.145(b), 
25.175(b), 25.671, and 25.1329(a).
    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 proposed 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 Airbus 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: side stick controllers for pitch and 
roll control in place of conventional wheels and columns.

Discussion

    Current FAA regulations do not specifically address the use of side 
stick controllers for pitch and roll control. The unique features of 
the side stick must therefore be demonstrated through flight and 
simulator tests to have suitable handling and control characteristics 
when considering the following:
    (1) The handling qualities tasks/requirements of the A350 Special 
Conditions and other 14 CFR part 25 requirements for stability, 
control, and maneuverability, including the effects of turbulence.
    (2) General ergonomics: Arm rest comfort and support, local freedom 
of movement, displacement angle suitability, and axis harmony.
    (3) Inadvertent input in turbulence.
    (4) Inadvertent pitch-roll cross talk.
    The Handling Qualities Rating Method (HQRM) of Appendix 5 of the 
Flight Test Guide, AC 25-7C, may be used to show compliance.

Applicability

    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.

Conclusion

    This action affects only certain novel or unusual design features 
on the Airbus Model A350-900 series 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 Airbus Model A350-900 series airplanes in the absence of specific 
requirements for side stick controllers:
    1. Pilot strength: In lieu of the ``strength of pilots'' limits 
shown in Sec.  25.143(c) for pitch and roll, and in lieu of specific 
pitch force requirement of Sec. Sec.  25.145(b) and 25.175(d), it must 
be shown that the temporary and maximum prolonged force levels for the 
side stick controllers are suitable for all expected operating 
conditions and configurations, whether normal or non-normal.
    2. Pilot control authority: The electronic side stick controller 
coupling design must provide for corrective and/or overriding control 
inputs by either pilot with no unsafe characteristics. Annunciation of 
the controller status must be provided, and must not be confusing to 
the flight crew.
    3. Pilot control: It must be shown by flight tests that the use of 
side stick controllers does not produce unsuitable pilot-in-the-loop 
control characteristics when considering precision path control/tasks 
and turbulence. In addition, pitch and roll control force and 
displacement sensitivity must be compatible, so that normal inputs on 
one control axis will not cause significant unintentional inputs on the 
other.

    Issued in Renton, Washington, on October 22, 2013.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-26912 Filed 11-7-13; 8:45 am]
BILLING CODE 4910-13-P