[Federal Register Volume 89, Number 52 (Friday, March 15, 2024)]
[Rules and Regulations]
[Pages 18767-18769]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-05661]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 25
[Docket No. FAA-2023-2437; Special Conditions No. 25-858-SC]
Special Conditions: Gulfstream Aerospace Corporation Model GVIII-
G700 and GVIII-G800 Series Airplanes; Flight Envelope Protection:
Takeoff Stall Protection
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final special conditions.
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SUMMARY: These special conditions are issued for the Gulfstream
Aerospace Corporation (Gulfstream) Model GVIII-G700 and GVIII-G800
series airplanes. These airplanes 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 an envelope protection function to protect the airplane from
over- and rapid-rotation on takeoff. 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 March 15, 2024.
FOR FURTHER INFORMATION CONTACT: Troy Brown, Performance and
Environment Unit, AIR-621A, Technical Policy Branch, Policy and
Standards Division, Aircraft Certification Service, Federal Aviation
Administration, 1801 S Airport Rd., Wichita, KS 67209-2190; telephone
and fax 405-666-1050; email [email protected].
SUPPLEMENTARY INFORMATION:
Background
On December 31, 2019, Gulfstream applied for an amendment to Type
Certificate No. T00015AT to include the new Model GVIII-G700 and GVIII-
G800 series airplanes. These airplanes, which will be derivatives of
the Model GVI currently approved under Type Certificate No. T00015AT,
are twin-engine, transport-category airplanes, with seating for 19
passengers, and a maximum take-off weight of 107,600 pounds (GVIII-
G700) and 105,600 pounds (GVIII-G800).
Type Certification Basis
Under the provisions of title 14, Code of Federal Regulations (14
CFR) 21.101, Gulfstream must show that the Model GVIII-G700 and GVIII-
G800 series airplanes meet the applicable provisions of the regulations
listed in Type Certificate No. T00015AT, or the applicable regulations
in effect on the date of application for the change, except for earlier
amendments as agreed upon by the FAA.
If the Administrator finds that the applicable airworthiness
regulations (e.g., 14 CFR part 25) do not contain adequate or
appropriate safety standards for the Gulfstream Model GVIII-G700 and
GVIII-G800 series airplanes because of a novel or unusual design
feature, special conditions are prescribed under the provisions of
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 novel or
unusual design feature, or should any other model already included on
the same type certificate be modified to incorporate the same novel or
unusual design feature, these special conditions
[[Page 18768]]
would also apply to the other model under Sec. 21.101.
In addition to the applicable airworthiness regulations and special
conditions, the Gulfstream Model GVIII-G700 and GVIII-G800 series
airplanes must comply with the 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, in
accordance with 14 CFR 11.38, and they become part of the type
certification basis under Sec. 21.101.
Novel or Unusual Design Features
The Gulfstream Model GVIII-G700 and GVIII-G800 airplanes will
incorporate the following novel or unusual design feature:
An envelope protection function within the electronic flight
control system (EFCS) to protect the airplane from over- and rapid-
rotation on takeoff.
Discussion
The Gulfstream Model GVIII-G700 and GVIII-G800 series airplanes are
equipped with an envelope protection function within the EFCS that is
designed to provide enhanced takeoff stall protection (TSP) function.
This feature protects against excessive pitch rate and pitch attitude
during takeoff using a limitation in the electronic flight controls. It
is designed to provide conventional behavior using a normal takeoff
technique, including ``performance'' takeoffs. The limit to pitch
attitude will indirectly limit the angle of attack.
The TSP involves a control law update in the on-ground control mode
only. The Model GVIII-G700 and GVIII-G800 series airplane's pitch
control behavior, with regard to rotation rates and attitudes for
normal takeoffs, will be similar to other Gulfstream airplanes equipped
with side sticks; however, takeoffs with rapid rotation rates and over-
rotation will be influenced by the TSP.
The current regulations in Subpart B of 14 CFR part 25 do not
address envelope protections for electronic flight control systems as
this technology is novel or unusual for transport category airplanes.
These special conditions are specific to the GVIII-G700 and GVIII-G800
series airplanes. These conditions are necessary to ensure that the TSP
function supports safe operation and does not interfere with required
maneuvering in normal and emergency operations and in foreseeable
atmospheric conditions.
The 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.
Discussion of Comments and Final Special Conditions
The FAA issued Notice of Proposed Special Conditions No. 25-24-01-
SC, for the GVIII-G700 and GVIII-G800 series airplanes. This Notice was
published in the Federal Register on January 18, 2024 (89 FR 3364). The
only comment the FAA received was from the applicant (Gulfstream).
Gulfstream requested that the FAA revise the third paragraph of the
Discussion section, to better reflect the content and scope of the
proposed special conditions. The FAA agrees with this comment as it
aligns with proposed regulation text from the Flight Test Harmonization
Working Group Phase 2 Rev A Final Report. The identified text has been
revised in a manner consistent with Gulfstream's request.\1\
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\1\ Specifically, the Discussion in Notice contained the
following text: ``These special conditions are specific to the
GVIII-700 and GVIII-G800 series airplanes. These conditions are
necessary to ensure a smooth transition from normal flight to the
TSP mode and adequate maneuver capability. These conditions also
ensure that the structural limits of the airplane are not exceeded.
Furthermore, failure of the TSP function must not create hazardous
flight conditions.'' This text is replaced in these final special
conditions with: ``These special conditions are specific to the
Takeoff Stall Protection Function of the GVIII-G700 and GVIII-G800
series airplanes. These conditions are necessary to ensure that the
TSP function supports safe operation and does not interfere with
required maneuvering in normal and emergency operations and in
foreseeable atmospheric conditions.''
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Gulfstream requested that the FAA remove certain text from the
first paragraph of the Discussion section. The FAA finds that the
referenced text is unnecessary for the Discussion and has removed it in
these final special conditions.
Gulfstream requested that the FAA revise the text of the Special
Conditions section (i.e., the requirements) to align with the text of
the Flight Test Harmonization Working Group Phase 2 Rev A Final
Report.\2\ The primary difference is that the proposed special
conditions included terms applicable to the ``takeoff stall protection
function,'' but the term in the Report, which Gulfstream requested to
be used, is the more general ``envelope protection function.'' The FAA
agrees with Gulfstream's request to make this change for consistency
with the terminology in the Report; but notes that the design feature
being addressed by these special conditions remains the same as
proposed. The FAA has also added ``simultaneous'' to the beginning of
paragraph (e) as a final conformance with the requested text of the
Report.
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\2\ The Report is available at https://www.faa.gov/regulations_policies/rulemaking/committees/documents/media/09%20-%20FTHWG_Final_Report_Phase_2_RevA__Apr_2017.pdf; the requested text
is at pages 43 and 221, and discussed beginning at page 238.
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Applicability
As discussed above, these special conditions are applicable to the
Gulfstream Model GVIII-G700 and GVIII-G800 series airplanes. Should
Gulfstream apply at a later date for a change to the type certificate
to include another model that incorporates the same novel or unusual
design feature, or should any other model already included on the same
type certificate be modified to incorporate the same novel or unusual
design feature, these special conditions would apply to the other model
as well.
Under standard practice, the effective date of final special
conditions would be 30 days after the date of publication in the
Federal Register. However, as the certification date for the Gulfstream
Model GVIII-G700 and GVIII-G800 is imminent, the FAA finds that good
cause exists to make these special conditions effective upon
publication.
Conclusion
This action affects only a certain novel or unusual design feature
on Gulfstream Model GVIII-G700 and GVIII-G800 series of airplanes. It
is not a rule of general applicability.
List of Subjects in 14 CFR Part 25
Aircraft, Aviation safety, Reporting and recordkeeping
requirements.
Authority Citation
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701, 44702, 44704.
The Special Conditions
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 GVIII-G700 and
GVIII-G800 series airplanes, and will be applied by the FAA to the
extent necessary to certify the envelope protection function within the
electronic flight control system (EFCS) that protects the airplane from
over- and rapid-rotation on takeoff.
For airplanes that employ envelope protection functions:
(a) Envelope protection functions must not unduly limit the
maneuvering capability of the airplane nor interfere with its ability
to perform maneuvers
[[Page 18769]]
required for normal and emergency operations.
(b) Onset characteristics of each envelope protection function must
be appropriate to the phase of flight and type of maneuver and must not
conflict with the ability of the pilot to satisfactorily control the
airplane flight path, speed, or attitude.
(c) Excursions of a limited flight parameter beyond its nominal
design limit value due to dynamic maneuvering, airframe and system
tolerances, and non-steady atmospheric conditions must not result in
unsafe flight characteristics or conditions.
(d) Operation of envelope protection functions must not adversely
affect aircraft control during expected levels of atmospheric
disturbances, nor impede the application of recovery procedures in case
of windshear.
(e) Simultaneous activation of envelope protection functions must
not result in adverse coupling or adverse priority.
(f) In case of abnormal attitude or excursion of any flight
parameters outside the protected boundaries, operation of envelope
protection functions must not hinder airplane recovery.
Issued in Kansas City, Missouri, on March 12, 2024.
James David Foltz,
Manager, Technical Policy Branch, Policy and Standards Division,
Aircraft Certification Service.
[FR Doc. 2024-05661 Filed 3-13-24; 11:15 am]
BILLING CODE 4910-13-P