Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-0481; Project Identifier AD-2024-00614-T]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; The Boeing Company Airplanes</SUBJECT> <HD SOURCE="HED">AGENCY:</HD> Federal Aviation Administration (FAA), DOT. <HD SOURCE="HED">ACTION:</HD> Notice of proposed rulemaking (NPRM). <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA proposes to supersede Airworthiness Directive (AD) 2023-09-04, which applies to certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, and certain Model 737-8 and -9 airplanes. AD 2023-09-04 requires inspecting all escape slide assemblies to identify affected parts and replacing affected escape slide assemblies with different assemblies. Since the FAA issued AD 2023-09-04, it was determined that additional airplanes might be affected by the unsafe condition. This proposed AD would retain the requirements of AD 2023-09-04 and require those actions for additional airplanes, including Model 737-8200 airplanes. The FAA is proposing this AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> The FAA must receive comments on this proposed AD by May 27, 2025. </EFFDATE> <HD SOURCE="HED">ADDRESSES:</HD> You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • <E T="03">Federal eRulemaking Portal:</E> Go to <E T="03">regulations.gov.</E> Follow the instructions for submitting comments. • <E T="03">Fax:</E> 202-493-2251. • <E T="03">Mail:</E> U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590. • <E T="03">Hand Delivery:</E> Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. <E T="03">AD Docket:</E> You may examine the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2025-0481; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, any comments received, and other information. The street address for Docket Operations is listed above. <E T="03">Material Incorporated by Reference:</E> • For the Boeing material identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 562-797-1717; website <E T="03">myboeingfleet.com.</E> • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206-231-3195. It is also available at <E T="03">regulations.gov</E> under Docket No. FAA-2025-0481. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Katherine Venegas, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: 562-627-5353; email: <E T="03">katherine.venegas@faa.gov.</E> </FURINF> <SUPLINF> <HD SOURCE="HED">SUPPLEMENTARY INFORMATION:</HD> <HD SOURCE="HD1">Comments Invited</HD> The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the <E T="02">ADDRESSES</E> section. Include “Docket No. FAA-2025-0481; Project Identifier AD-2024-00614-T” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. 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">regulations.gov,</E> including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. <HD SOURCE="HD1">Confidential Business Information</HD> 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 this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, 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 they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Katherine Venegas, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: 562-627-5353; email: <E T="03">katherine.venegas@faa.gov.</E> Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking. <HD SOURCE="HD1">Background</HD> The FAA issued AD 2023-09-04, Amendment 39-22427 (88 FR 33817, May 25, 2023) (AD 2023-09-04), for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes, and certain Model 737-8 and -9 airplanes. AD 2023-09-04 was prompted by reports of uncommanded escape slide deployments in the passenger compartment while the airplane was on the ground, caused by too much tension in the inflation cable (introduced during packing of the slide) and the movement of the escape slide assembly in the escape slide compartment during normal airplane operations. AD 2023-09-04 requires inspecting all escape slide assemblies to identify affected parts and replacing affected escape slide assemblies with different assemblies. The agency issued AD 2023-09-04 to address inflation of the escape slide while it is in the escape slide compartment, which could result in injury to passengers and crew during normal operation or impede an emergency evacuation by rendering the exit unusable. <HD SOURCE="HD1">Actions Since AD 2023-09-04 Was Issued</HD> Since the FAA issued AD 2023-09-04, the FAA determined that additional airplanes might be affected by the unsafe condition. AD 2023-09-04 applies to airplanes identified by line number in Boeing Special Attention Requirements Bulletin 737-25-1855 RB, Revision 1, dated April 13, 2022; and Boeing Special Attention Requirements Bulletin 737-25-1866 RB, Revision 1, dated April 11, 2022. However, the FAA has determined that additional line-numbered airplanes, as well as Model 737-8200 airplanes, might have an affected escape slide assembly installed because the part is rotable. Since the affected parts are rotable, they could later be installed on airplanes that were initially delivered with acceptable parts, thereby creating an unsafe condition in those airplanes. In addition, Boeing issued Special Attention Requirements Bulletin 737-25-1866 RB, Revision 2, dated July 19, 2024, to revise the applicable airplanes in the effectivity paragraph of Boeing Special Attention Requirements Bulletin 737-25-1866 RB, Revision 1, dated April 11, 2022. The FAA proposes to retain the requirements of AD 2023-09-04 and also require that all Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes and Model 737-8, 737-9, and 737-8200 airplanes that are excluded from the applicability of AD 2023-09-04 inspect all escape slide assemblies to identify affected parts and accomplish applicable on-condition actions. The FAA has determined that these actions can be accomplished using Boeing Special Attention Requirements Bulletin 737-25-1855 RB, Revision 1, dated April 13, 2022 (for all Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes); and Boeing Special Attention Requirements Bulletin 737-25-1866 RB, Revision 1, dated April 11, 2022 (for all Model 737-8, 737-9, and 737-8200 airplanes), regardless of whether the airplane model or line number is identified in those bulletins. <HD SOURCE="HD1">FAA's Determination</HD> The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design. <HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD> The FAA reviewed Boeing Special Attention Requirements Bulletin 737-25-1866 RB, Revision 2, dated July 19, 2024. This material specifies procedures for inspecting all escape slide assemblies to identify any escape slide assembly having part number (P/N) 5A3307-7 and replacing it with an assembly having P/N 5A3307-9 or P/N 5A3307-701. Escape slide assembly P/N 5A3307-701 is one on which a firing cable retention has been modified and the assembly reidentified with a new part number. This proposed AD would also require Boeing Special Attention Requirements Bulletin 737-25-1855 RB, Revision 1, dated April 13, 2022; and Boeing Special Attention Requirements Bulletin 737-25-1866 RB, Revision 1, dated April 11, 2022, which the Director of the Federal Register approved for incorporation by reference as of June 29, 2023 (88 FR 33817, May 25, 2023). This material is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the <E T="02">ADDRESSES</E> section. <HD SOURCE="HD1">Proposed AD Requirements in This NPRM</HD> This proposed AD would retain all requirements of AD 2023-09-04. This proposed AD would also req ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 26k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━