Special Conditions: H4 Aerospace (UK) Ltd., Boeing Model 757-200 Airplane, Non-Rechargeable Lithium Battery and Battery System Installations

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 25</CFR> <DEPDOC>[Docket No. FAA-2023-2134; Special Conditions No. 25-845-SC]</DEPDOC> <SUBJECT>Special Conditions: H4 Aerospace (UK) Ltd., Boeing Model 757-200 Airplane, Non-Rechargeable Lithium Battery and Battery System Installations</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 non-rechargeable lithium batteries and battery systems on Boeing Model 757-200 airplanes, as modified by H4 Aerospace (UK) Ltd (H4). Non-rechargeable lithium batteries are a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. 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 H4 on May 15, 2024. Send comments on or before July 1, 2024. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> Send comments identified by Docket No. FAA-2023-2134 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> Nazih Khaouly, Electrical Systems Unit, AIR-626A, Technical Policy Branch, Policy and Standards Division, Aircraft Certification Service, Federal Aviation Administration, 2200 South 216th Street, Des Moines, Washington 98198; telephone (206) 231-3160; email <E T="03">Nazih.Khaouly@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 Title 14, Code of Federal Regulations (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 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 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. <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 and will consider comments filed late if it is possible to do so without incurring delay. The FAA may change these special conditions based on the comments received. <HD SOURCE="HD1">Background</HD> On February 26, 2020, H4 applied for a supplemental type certificate to install, on the Boeing 757-200 airplane, HR Smith emergency locator transmitter (ELT) 500-32-2Y-H that contain a non-rechargeable lithium battery and battery system. The Boeing Model 757-200 airplane currently approved under Type Certificate No A2NM, are twin-engine transport category airplanes with a maximum seating of capacity of 295 passengers and has a maximum takeoff weight of 255,000 pounds. <HD SOURCE="HD1">Type Certification Basis</HD> Under the provisions of title 14, Code of Federal Regulations (14 CFR) 21.101, H4 must show that the Boeing Model 757-200 airplane, as changed, continues to meet the applicable provisions of the regulations listed in Type Certificate No. A2NM 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 Boeing Model 757-200 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 Boeing Model 757-200 airplane must comply with the exhaust-emission requirements of 14 CFR part 34, and the noise-certification requirements of 14 CFR part 36. <HD SOURCE="HD1">Novel or Unusual Design Feature</HD> The Boeing Model 757-200, MSN 25140 and MSN 24473 airplanes will incorporate the following novel or unusual design feature: The installation of an HR Smith emergency locator transmitter (ELT) 500-32-2Y-H containing a non-rechargeable lithium battery and battery system. <HD SOURCE="HD1">Discussion</HD> The FAA derived the current regulations governing installation of batteries in transport category airplanes from Civil Air Regulations (CAR) 4b.625(d) as part of the recodification of CAR 4b that established <E T="03">14 CFR part 25</E> in February 1965. This recodification basically reworded the CAR 4b battery requirements, which are currently in §  25.1353(b)(1) through (4). Non-rechargeable lithium batteries are novel and unusual with respect to the state of technology considered when these requirements were codified. Non-rechargeable lithium batteries introduce higher energy levels into airplane systems through new chemical compositions in various battery cell sizes and construction. Interconnection of these cells in battery packs introduce failure modes that require unique design considerations, such as provisions for thermal management. In January 2013, two independent events involving rechargeable lithium batteries revealed unanticipated failure modes. A National Transportation Safety Board (NTSB) Safety Recommendation to the FAA, dated May 22, 2014, which is available at <E T="03">www.ntsb.gov,</E> filename A-14-032-036.pdf, describes these events. On July 12, 2013, an event involving a non-rechargeable lithium battery in an emergency-locator transmitter installation demonstrated unanticipated failure modes. The United Kingdom's Air Accidents Investigation Branch Bulletin S5/2013  <SU>1</SU> <FTREF/> describes this event. These events involving rechargeable and non-rechargeable lithium batteries prompted the FAA to initiate a broad evaluation of these energy-storage technologies. <FTNT> <SU>1</SU>   <E T="03">See</E> S5-2013_ET-AOP.pdf, available in the docket for these special conditions. </FTNT> On April 22, 2016, the FAA published special conditions no. 25-612-SC, in the <E T="04">Federal Register</E> ( <E T="03">81 FR 23573</E> ), applicable to Gulfstream Aerospace Corporation for the Model GVI airplane. Those were the first special conditions the FAA issued for non-rechargeable lithium battery installations. In that document, the FAA explained its decision to make those ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 19k characters. 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