Document ID: FAA-2013-0899-0001
Agency: faa
Document Type: Proposed Rule
Title: Special Conditions: Airbus, Model A350-900 Series Airplane; Control Surface Awareness And Mode Annunciation
Posted Date: 2013-12-17T05:00Z

[Federal Register Volume 78, Number 242 (Tuesday, December 17, 2013)]
[Proposed Rules]
[Pages 76254-76255]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-29988]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2013-0899; Notice No. 25-13-15-SC]

Special Conditions: Airbus, Model A350-900 Series Airplane; 
Control Surface Awareness and Mode Annunciation

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 control surface awareness and mode 
annunciation provided by the electronic flight control system. 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 January 31, 2014.

ADDRESSES: Send comments identified by docket number FAA-2013-0899 
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-
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 proposed 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 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 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.
    These proposed special conditions for control surface awareness, 
applicable to Airbus Model A350-900 series airplanes, propose suitable 
flight control position annunciation and control system mode of 
operation to be provided to the flight crew when a flight condition 
exists in which nearly full surface authority (not crew-commanded) is 
being utilized. Suitability of such a display must take into account 
that some pilot-demanded maneuvers (e.g., rapid roll) are necessarily 
associated with intended full performance, which may saturate the 
surface. Therefore, simple alerting systems, which would function in 
both intended or unexpected control-limiting situations, must be 
properly balanced between needed crew awareness and nuisance features. 
A monitoring system that might compare airplane motion and surface 
deflection, and pilot side stick controller (SSC) demand could be 
useful for elimination of nuisance alerting.

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-
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 or similar 
novel or unusual design feature, the proposed special conditions would 
also apply to the other model under Sec.  21.101.

[[Page 76255]]

    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 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, 
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: electronic flight control system 
providing control surface awareness and mode annunciation to the 
flightcrew.

Discussion

    With a response-command type flight control system and no direct 
coupling from cockpit controller to control surface, the pilot is not 
aware of actual surface position utilized to fulfill the requested 
demand. Some unusual flight conditions, arising from atmospheric 
conditions and/or airplane or engine failures, may result in full or 
nearly full surface deflection. Unless the flightcrew is made aware of 
excessive deflection or impending control surface limiting, piloted or 
auto-flight system control of the airplane might be inadvertently 
continued in such a manner to cause loss of control or other unsafe 
stability or performance characteristics.

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.

0
1. Current airworthiness standards do not contain adequate safety 
standards for the proposed design. In addition to the requirements of 
Sec. Sec.  25.143, 25.671 and 25.672, the following proposed special 
conditions apply:
0
a. The system design must ensure that the flight crew is made suitably 
aware whenever the primary control means nears the limit of control 
authority.
    Note: The term ``suitably aware'' indicates annunciations provided 
to the flight crew that are appropriately balanced between nuisance and 
that are necessary for crew awareness.
0
b. If the design of the flight control system has multiple modes of 
operation, a means must be provided to indicate to the crew any mode 
that significantly changes or degrades the normal handling or 
operational characteristics of the airplane.

    Issued in Renton, Washington, on October 22, 2013.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-29988 Filed 12-16-13; 8:45 am]
BILLING CODE 4910-13-P