[Federal Register Volume 76, Number 30 (Monday, February 14, 2011)]
[Proposed Rules]
[Pages 8319-8321]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-3216]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. NM441 Special Conditions No. 25-11-01-SC]
Special Conditions: Gulfstream Model GVI Airplane; Design Roll
Maneuver Requirement for Electronic Flight Controls
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed special conditions.
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SUMMARY: This action proposes special conditions for the Gulfstream GVI
airplane. This airplane will have novel or unusual design features when
compared to the state of technology envisioned in the airworthiness
standards for transport category airplanes. These design features
include an electronic flight control system that provides roll control
of the airplane through pilot inputs to the flight
[[Page 8320]]
computers. 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: We must receive your comments by March 31, 2011.
ADDRESSES: You must mail two copies of your comments to: Federal
Aviation Administration, Transport Airplane Directorate, Attn: Rules
Docket (ANM-113), Docket No. NM441, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356. You may deliver two copies to the Transport
Airplane Directorate at the above address. You must mark your comments:
Docket No. NM441. You can inspect comments in the Rules Docket
weekdays, except Federal holidays, between 7:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: Carl Niedermeyer, FAA, Airframe/Cabin
Safety Branch, ANM-115, Transport Standards Staff, Transport Airplane
Directorate, Aircraft Certification Service, 1601 Lind Avenue, SW.,
Renton, Washington 98057-3356; telephone (425) 227-2279; 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 ask
that you send us two copies of written comments.
We will file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning these special conditions. You can inspect the docket before
and after the comment closing date. If you wish to review the docket in
person, go to the address in the ADDRESSES section of this preamble
between 7:30 a.m. and 4 p.m., Monday through Friday, except Federal
holidays.
We will consider all comments we receive on or before the closing
date for comments. We will consider comments filed late if it is
possible to do so without incurring expense or delay. We may change
these special conditions based on the comments we receive.
If you want us to acknowledge receipt of your comments on this
proposal, include with your comments a self-addressed, stamped postcard
on which you have written the docket number. We will stamp the date on
the postcard and mail it back to you.
Background
On March 29, 2005, Gulfstream Aerospace Corporation (hereafter
referred to as ``Gulfstream'') applied for an FAA type certificate for
its new Gulfstream Model GVI passenger airplane. Gulfstream later
applied for, and was granted, an extension of time for the type
certificate, which changed the effective application date to September
28, 2006. The Gulfstream Model GVI airplane will be an all-new, two-
engine jet transport airplane with an executive cabin interior. The
maximum takeoff weight will be 99,600 pounds, with a maximum passenger
count of 19 passengers.
Type Certification Basis
Under provisions of Title 14, Code of Federal Regulations (14 CFR)
21.17, Gulfstream must show that the Gulfstream Model GVI airplane
(hereafter referred to as ``the GVI'') meets the applicable provisions
of 14 CFR part 25, as amended by Amendments 25-1 through 25-119, 25-
122, and 25-124. 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 GVI because of a novel
or unusual design feature, special conditions are prescribed under the
provisions of Sec. 21.16.
In addition to complying with the applicable airworthiness
regulations and special conditions, the GVI 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 must also issue a
finding of regulatory adequacy pursuant to 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, in
accordance with Sec. 11.38, and they become part of the type
certification basis under Sec. 21.17(a)(2).
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 features, the special conditions would also apply to the
other model under provisions of Sec. 21.101.
Novel or Unusual Design Features
The GVI is equipped with an electronic flight control system that
provides roll control of the airplane through pilot inputs to the
flight computers. The current design roll maneuver requirement for
structural loads in 14 CFR part 25 is inadequate for addressing an
airplane with electronic flight controls that affect maneuvering.
Special conditions are proposed to take into account the effects of an
electronic flight control system.
Discussion of Proposed Special Conditions
The GVI is equipped with an electronic flight control system that
provides roll control of the airplane through pilot inputs to the
flight computers. Current part 25 airworthiness regulations account for
``control laws'' for which aileron deflection is proportional to
control wheel deflection. They do not address any nonlinearities \1\ or
other effects on aileron and spoiler actuation that may be caused by
electronic flight controls. Therefore, the FAA considers the flight
control system to be a novel and unusual feature compared to those
envisioned when the current regulations were adopted. Since this type
of system may affect flight loads, and therefore the structural
capability of the airplane, special conditions are needed to address
these effects.
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\1\ A nonlinearity is a situation where output does not change
in the same proportion as input.
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These proposed special conditions differ from current requirements
in that the special conditions require that the roll maneuver result
from defined movements of the cockpit roll control as opposed to
defined aileron deflections. Also, these proposed special conditions
require an additional load condition at design maneuvering speed
(VA), in which the cockpit roll control is returned to
neutral following the initial roll input.
Applicability
As discussed above, these proposed special conditions are
applicable to the GVI. Should Gulfstream apply at a later date for a
change to the type certificate to include another model incorporating
the same novel or unusual design features, these proposed special
conditions would apply to that model as well.
Conclusion
This action affects only certain novel or unusual design features
of the GVI. 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:
[[Page 8321]]
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 the GVI airplanes.
In lieu of compliance with Sec. 25.349(a), Gulfstream must comply
with the following special 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.
25.301(b):
1. 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.
2. 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.
3. 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 2.
4. 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 2.
Issued in Renton, Washington, on February 3, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-3216 Filed 2-11-11; 8:45 am]
BILLING CODE 4910-13-P