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[Federal Register Volume 80, Number 159 (Tuesday, August 18, 2015)]
[Proposed Rules]
[Pages 49934-49936]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-20298]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2015-1496; Notice No. 25-15-07-SC]

Special Conditions: Gulfstream Model GVII-G500 Airplanes, Side-
Stick Controllers; Controllability and Maneuverability

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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SUMMARY: This action proposes special conditions for Gulfstream Model 
GVII-G500 airplanes. These airplanes will have a novel or unusual 
design feature associated with side-stick controllers, instead of 
conventional-control wheel-and-column design, for pitch and roll 
control. 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 October 2, 2015.

ADDRESSES: Send comments identified by docket number FAA-2015-1496 
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.

[[Page 49935]]

    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/ 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 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-
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 by the closing date for 
comments. We may change these proposed special conditions based on the 
comments we receive.

Background

    On March 29, 2012, Gulfstream Aerospace Corporation applied for a 
type certificate for their new Model GVII-G500 airplane. The Model 
GVII-G500 will be a large-cabin business jet with seating for 19 
passengers. It will incorporate a low, swept-wing design with winglets 
and a T-tail. The powerplant will consist of two aft-fuselage-mounted 
Pratt & Whitney turbofan engines. Avionics will include four primary 
display units and multiple touchscreen controllers. The flight-control 
system is a three-axis, fly-by-wire (FBW) system incorporating active 
control/coupled side sticks.
    The Model GVII-G500 will have a wingspan of approximately 87 ft. 
and a length of just over 91 ft. Maximum takeoff weight will be 
approximately 76,850 lbs and maximum takeoff thrust will be 
approximately 15,135 lbs. Maximum range will be approximately 5,000 nm 
and maximum operating altitude will be 51,000 ft.
    The Model GVII-G500 airplane will incorporate a FBW flight-control 
system, through side-stick controllers, for pitch and roll control. 
Regulatory requirements, such as the pilot-control forces prescribed in 
the referenced regulations, are not applicable for the side-stick 
controller design. In addition, pilot-control authority may be 
uncertain because the side-stick controllers are not mechanically 
interconnected to flight controls as are conventional wheel-and-column 
controls.

Type Certification Basis

    Under Title 14, Code of Federal Regulations (14 CFR) 21.17, 
Gulfstream must show that the Model GVII-G500 airplane meets the 
applicable provisions of 14 CFR part 25, effective February 1, 1965, 
including Amendments 25-1 through 25-137; 14 CFR part 34, as amended by 
Amendments 34-1 through the most current amendment at time of design 
approval; and 14 CFR part 36, Amendment 36-29.
    In addition, the certification basis includes other regulations, 
special conditions, and exemptions that are not relevant to these 
proposed special conditions. Type Certificate no. TC-01-2010-0024 will 
be updated to include a complete description of the certification basis 
for this airplane model.
    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 Gulfstream Model GVII-G500 
airplane 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, Gulfstream Model GVII-G500 airplanes 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

    Gulfstream Model GVII-G500 airplanes will incorporate the following 
novel or unusual design feature:
    Side-stick controllers incorporating fly-by-wire technology for 
pitch and roll control, in place of conventional wheel-and-column 
controls.

Discussion

    These proposed special conditions for the Gulfstream Model GVII-
G500 airplane address the unique features of the side-stick 
controllers. The Model GVII-G500 airplane will incorporate side-stick 
controllers controlling a FBW flight-control system. The FBW control 
laws are designed to provide conventional flying qualities such as 
positive static longitudinal and lateral stability as prescribed in 
part 25, subpart B. However, the pilot-control forces prescribed in the 
referenced regulations are not applicable for the side-stick controller 
design.
    Because 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 therefore must be demonstrated, through 
flight and simulator tests, to have suitable handling and control 
characteristics when considering the following:
     The handling-qualities tasks and requirements of the 
Gulfstream Model GVII-G500 Special Conditions and other 14 CFR part 25 
requirements for stability, control, and maneuverability, including the 
effects of turbulence.
     General ergonomics: Armrest comfort and support, local 
freedom of movement, displacement-angle suitability, and axis harmony.
     Inadvertent pilot input in turbulence.
     Inadvertent pitch and roll crosstalk from pilot inputs on 
the side-stick controller.

Applicability

    As discussed above, these proposed special conditions apply to 
Gulfstream Model GVII-G500 airplanes. Should Gulfstream apply later for 
a change to the type certificate to include another model incorporating 
the same or similar novel or unusual design feature, the proposed 
special conditions would apply to that model as well.

[[Page 49936]]

Conclusion

    This action affects only certain novel or unusual design features 
on Gulfstream Model GVII-G500 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

    The current airworthiness regulations pertaining to pilot strength 
and controllability for conventional-control column-and-wheel designs 
do not adequately address the side-stick controllers proposed for the 
Gulfstream Model GVII-G500 airplane. Accordingly, the FAA proposes the 
following special conditions as part of the type certification basis 
for Gulfstream GVII-G500 airplanes, in lieu of Sec. Sec.  25.143(d), 
25.143(i)(2), 25.145(b), 25.173(c), 25.175(b), and 25.175(d):
    Pilot strength: In lieu of the control-force limits shown in Sec.  
25.143(d) for pitch and roll, and in lieu of specific pitch-force 
requirements of Sec. Sec.  25.143(i)(2), 25.145(b), 25.173(c), 
25.175(b), and 25.175(d), Gulfstream must show 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.
    Pilot-control authority: The electronic side-stick-controller 
coupling design must provide for corrective and 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 flightcrew.
    Pilot control: Gulfstream must show 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 and 
tasks, and turbulence. In addition, pitch and roll control force and 
displacement sensitivity must be compatible, so that normal pilot 
inputs on one control axis will not cause significant unintentional 
inputs (crossover) on the other.

    Issued in Renton, Washington, on August 5, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-20298 Filed 8-17-15; 8:45 am]
BILLING CODE 4910-13-P
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