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[Federal Register Volume 80, Number 192 (Monday, October 5, 2015)]
[Rules and Regulations]
[Pages 60027-60028]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-25276]

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Rules and Regulations
                                                Federal Register
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This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

The Code of Federal Regulations is sold by the Superintendent of Documents. 
Prices of new books are listed in the first FEDERAL REGISTER issue of each 
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Federal Register / Vol. 80, No. 192 / Monday, October 5, 2015 / Rules 
and Regulations

[[Page 60027]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR part 25

[Docket No. FAA-2015-1496; Special Conditions No. 25-601-SC]

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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions.

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SUMMARY: These special conditions are issued for the Gulfstream Model 
GVII-G500 airplane. This airplane will have a novel or unusual design 
feature when compared to the state of technology envisioned in the 
airworthiness standards for transport category airplanes. This design 
feature is 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 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: Effective November 4, 2015.

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:

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. 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 
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 special conditions would also 
apply to the other model under Sec.  21.101.
    In addition to the applicable airworthiness regulations and 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.
    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 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.

[[Page 60028]]

     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.

Discussion of Comments

    Notice of proposed special conditions no. 25-15-07-SC for the 
Gulfstream Model GVII-G500 airplane was published in the Federal 
Register on August 18, 2015 [80 FR 49934]. No comments were received, 
and the special conditions are adopted as proposed.

Applicability

    As discussed above, these 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 special conditions 
would apply to that model as well.

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.

0
The authority citation for these special conditions is as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701, 44702, 44704.

The Special Conditions

0
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 the Gulfstream Model GVII-G500 
airplane, 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, September 25, 2015.
Michael Kaszycki,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-25276 Filed 10-2-15; 8:45 am]
 BILLING CODE 4910-13-P
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