[Federal Register Volume 90, Number 156 (Friday, August 15, 2025)]
[Rules and Regulations]
[Pages 39313-39314]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-15630]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 25

[Docket No. FAA-2025-1624; Special Conditions No. 25-883-SC]


Special Conditions: Jet Aviation AG, Gulfstream Aerospace 
Corporation Model GVI Airplane; Installation of Therapeutic Oxygen 
System

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Gulfstream 
Aerospace Corporation (Gulfstream) Model GVI airplane. This airplane, 
as modified by Jet Aviation AG, 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 oxygen distribution system that provides a shared source 
of oxygen between the flightcrew and passengers to provide supplemental 
and therapeutic oxygen. 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: This action is effective on Jet Aviation AG on August 15, 2025. 
Send comments on or before September 29, 2025.

ADDRESSES: Send comments identified by Docket No. FAA-2025-1624 using 
any of the following methods:
     Federal eRegulations Portal: Go to 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.
    Docket: Background documents or comments received may be read at 
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: Robert Hettman, FAA-Aircraft 
Certification Policy and Standards Division, AIR-623, Technical Policy 
Branch Policy and Standards Division, Aircraft Certification Service, 
Federal Aviation Administration, 2200 South 216th Street, Des Moines, 
Washington 98198; telephone 206-231-3171; email [email protected].

SUPPLEMENTARY INFORMATION: The substance of these special conditions 
has been published in the Federal Register for public comment in 
several prior instances with no substantive comments received. 
Therefore, the FAA finds, pursuant to 14 CFR 11.38(b), that new 
comments are unlikely, and notice and comment prior to this publication 
are unnecessary.

Privacy

    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in title 
14, Code of Federal Regulations (14 CFR) 11.35, the FAA will post all 
comments received without change to www.regulations.gov, including any 
personal information you provide. The FAA will also post a report 
summarizing each substantive verbal contact received about these 
special conditions.

Confidential Business Information

    Confidential Business Information (CBI) is commercial or financial 
information that is both customarily and actually treated as private by 
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), 
CBI is exempt from public disclosure. If your comments responsive to 
these special conditions contain commercial or financial information 
that is customarily treated as private, that you actually treat as 
private, and that is relevant or responsive to these special 
conditions, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and the indicated comments will not be 
placed in the public docket of these proposed special conditions. Send 
submissions containing CBI to the individual listed in the For Further 
Information Contact section above. Comments the FAA receives, which are 
not specifically designated as CBI, will be placed in the public docket 
for these proposed special conditions.

Comments Invited

    The FAA invites 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.
    The FAA will consider all comments received by the closing date for 
comments. The FAA may change these special conditions based on the 
comments received.

Background

    On July 9, 2024, Jet Aviation AG applied for a supplemental type 
certificate for the installation of therapeutic oxygen systems on the 
Model GVI airplane. The Gulfstream Model GVI airplane, currently 
approved under Type Certificate No. T00015AT, is a twin-engine 
transport-category, business jet, with a maximum seating for 19 
passengers, and a maximum take-off weight of 99,600 pounds.

Type Certification Basis

    Under the provisions of title 14, Code of Federal Regulations (14 
CFR) 21.101, Jet Aviation AG must show that the changes to the 
Gulfstream Model GVI airplane, as changed, continues to 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 GVI airplane 
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 applicant apply for a supplemental type 
certificate to modify any other model included on the same type 
certificate to incorporate the same novel or unusual design feature, 
these special conditions would also apply to the other model under 
Sec.  21.101.
    In addition to the applicable airworthiness regulations and special 
conditions, the Gulfstream Model GVI

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airplane 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 Sec.  11.38, and they become part of the type 
certification basis under Sec.  21.101.

Novel or Unusual Design Features

    The Gulfstream Model GVI airplane will incorporate the following 
novel or unusual design feature:
    An oxygen distribution system that provides a shared source of 
oxygen between the flightcrew and passengers to provide supplemental 
and therapeutic oxygen.

Discussion

    There are no specific regulations that address the design and 
installation of required passenger or crew oxygen systems that share a 
supply source with an optional oxygen system used specifically for 
therapeutic applications. Therapeutic oxygen systems have been 
previously certified and were generally considered an extension of the 
passenger oxygen system for the purpose of defining the applicable 
regulations. As a result, existing requirements, such as 14 CFR 
25.1309, 25.1441(b) and (c), 25.1451, and 25.1453, in the Gulfstream 
GVI airplane's certification basis applicable to this project, provide 
some design standards appropriate for oxygen system installations. In 
addition, Sec.  25.1445 includes standards for oxygen distribution 
systems when oxygen is supplied to crew and passengers. If a common 
source of supply is used, Sec.  25.1445(a)(2) requires a means to 
separately reserve the minimum supply required by the flight crew.
    Section 25.1445 is intended to protect the flightcrew by ensuring 
that an adequate supply of oxygen is available to complete a descent 
and landing following a loss of cabin pressure. When the regulation was 
written, the only passenger oxygen system designs were supplemental 
oxygen systems intended to protect passengers from hypoxia in the event 
of a decompression. Existing passenger oxygen systems did not include 
design features that would allow the flightcrew to control oxygen to 
passengers during flight. There are no similar requirements in Sec.  
25.1445 when oxygen is supplied from the same source to passengers for 
use during a decompression, and for discretionary or first-aid use any 
time during the flight. In the design, the crew, passenger, and 
therapeutic oxygen systems use the same source of oxygen. These special 
conditions contain additional design requirements for the equipment 
involved in this dual therapeutic oxygen plus supplemental gaseous 
oxygen installation.
    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.

Applicability

    As discussed above, these special conditions are applicable to the 
Gulfstream Model GVI airplane. Should Jet Aviation AG apply at a later 
date for a supplemental type certificate to modify any other model 
included on Type Certificate No. T00015AT to incorporate the same novel 
or unusual design feature, these special conditions would apply to that 
model as well.

Conclusion

    This action affects only a certain novel or unusual design feature 
on one model of airplane. It is not a rule of general applicability and 
affects only the applicant who applied to the FAA for approval of these 
features on the airplane.

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), 40113, 44701, 44702, and 44704.

The Special Conditions

    [ssquf] 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 Gulfstream Aerospace Corporation 
Model GVI airplanes, as modified by Jet Aviation AG.
    The distribution system for the passenger therapeutic oxygen system 
must be designed and installed to meet the following requirements:
    (1) When oxygen is supplied to passengers for both supplemental and 
therapeutic purposes, the distribution system must be designed for 
either--
    (a) A source of supplemental oxygen for protection following a loss 
of cabin pressure, and a separate source for therapeutic purposes; or
    (b) A common source of supply with means to separately reserve the 
minimum supply required by the passengers for supplemental use 
following a loss of cabin pressure.

    Issued in in Kansas City, Missouri, on August 13, 2025.
Patrick R. Mullen,
Manager, Technical Policy Branch, Policy and Standards Division, 
Aircraft Certification Service.
[FR Doc. 2025-15630 Filed 8-14-25; 8:45 am]
BILLING CODE 4910-13-P