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

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 25</CFR> <DEPDOC>[Docket No. FAA-2025-1624; Special Conditions No. 25-883-SC]</DEPDOC> <SUBJECT>Special Conditions: Jet Aviation AG, Gulfstream Aerospace Corporation Model GVI Airplane; Installation of Therapeutic Oxygen System</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Final special conditions; request for comments. <SUM> <HD SOURCE="HED">SUMMARY:</HD> 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. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This action is effective on Jet Aviation AG on August 15, 2025. Send comments on or before September 29, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Send comments identified by Docket No. FAA-2025-1624 using any of the following methods: • <E T="03">Federal eRegulations Portal:</E> Go to <E T="03">www.regulations.gov</E> and follow the online instructions for sending your comments electronically. • <E T="03">Mail:</E> 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. • <E T="03">Hand Delivery or Courier:</E> 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. • <E T="03">Fax:</E> Fax comments to Docket Operations at 202-493-2251. <E T="03">Docket:</E> Background documents or comments received may be read at <E T="03">www.regulations.gov</E> 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. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> 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 <E T="03">robert.hettman@faa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> The substance of these special conditions has been published in the <E T="04">Federal Register</E> 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. <HD SOURCE="HD1">Privacy</HD> 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 <E T="03">www.regulations.gov,</E> including any personal information you provide. The FAA will also post a report summarizing each substantive verbal contact received about these special conditions. <HD SOURCE="HD1">Confidential Business Information</HD> 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 <E T="02">For Further Information Contact</E> 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. <HD SOURCE="HD1">Comments Invited</HD> 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. <HD SOURCE="HD1">Background</HD> 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. <HD SOURCE="HD1">Type Certification Basis</HD> 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 T="03">e.g.,</E> 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 § 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 § 21.101. In addition to the applicable airworthiness regulations and special conditions, the Gulfstream Model GVI 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 § 11.38, and they become part of the type certification basis under § 21.101. <HD SOURCE="HD1">Novel or Unusual Design Features</HD> 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. <HD SOURCE="HD1">Discussion</HD> 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, § 25.1445 includes standards for oxygen distribution systems when oxygen is supplied to crew and passengers. If a common source of supply is used, § 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 § 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 ad ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 12k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━