Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-2275; Project Identifier AD-2025-00796-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 adopt a new airworthiness directive (AD) for certain The Boeing Company Model 757-200 and -300 series airplanes. This proposed AD was prompted by a determination that new or more restrictive airworthiness limitations are necessary. This proposed AD would require revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. 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 October 23, 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-2025-2275; 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 Aviation Partners Boeing material identified in this proposed AD, contact Aviation Partners Boeing, 555 Andover Park West, Suite 200, Tukwila, WA 98188; telephone 206-830-7699; fax 206-767-0535; email <E T="03">leng@aviationpartners.com;</E> website <E T="03">aviationpartnersboeing.com.</E> • You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Sarah Illg, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: 206-231-3517; email: <E T="03">Sarah.A.Illg@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 using a method listed under the <E T="02">ADDRESSES</E> section. Include “Docket No. FAA-2025-2275; Project Identifier AD-2025-00796-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 Sarah Illg, Aviation Safety Engineer, FAA, 3960 Paramount Boulevard, Lakewood, CA 90712; phone: 206-231-3517; email: <E T="03">Sarah.A.Illg@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 2020-01-18, Amendment 39-19824 (85 FR 5304, January 30, 2020); corrected February 26, 2020 (85 FR 10969) (AD 2020-01-18), for all the Boeing Company Model 757 airplanes. AD 2020-01-18 requires revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. AD 2020-01-18 includes a requirement to revise the existing maintenance or inspection program to incorporate a supplemental program to address the effect of Supplemental Type Certificate (STC) ST01518SE. The FAA issued AD 2020-01-18 to address fatigue cracking of the principal structural elements, which could adversely affect the structural integrity of the airplane. Since the FAA issued AD 2020-01-18, the FAA has received an operator report indicating that during a maintenance H-check inspection, a crack was found at the splice fitting between the original wing and the Aviation Partners Boeing (APB) modified lower wing skin panel, which is spliced at wing station (WS) 711 on a Boeing Company Model 757-200 airplane with the APB blended winglets installed in accordance with STC ST01518SE. APB reviewed the crack finding and determined the existing airworthiness limitations (AWL) structural significant items (SSI) 57-20- 32B does not provide adequate probability of detection for foreseeable fatigue cracking of SSIs at station WS 711. If cracks grow undetected, it may result in the inability of a principal structural element to sustain limit loads. The FAA has determined that it is necessary to revise the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations for The Boeing Company Model 757-200 and -300 airplanes that have been modified in accordance with STC ST01518SE, with or without blended or scimitar blended winglets installed. Incorporating the revision required by this proposed AD would terminate the requirements of paragraphs (g) and (h)(2) of AD 2020-01-18. The FAA is proposing this AD to address the potential for fatigue cracking on the wing and winglet. This condition, if not addressed, could result in the inability of a principal structural element to sustain limit loads, which could adversely affect the structural integrity of the airplane. <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 Aviation Partners Boeing AP57.2-0604.2 Supplement to D622N001-9 (September 2020) 757 Maintenance Planning Data (MPD) document, Section 9, Airworthiness Limitations (AWLs) and Certification Requirements (CMRs) Boeing 757-200 with Winglets FAA STC NUMBER ST01518SE AND EASA STC NUMBER 10015659, Revision February 2022; and AP57.3-0604.2 Supplement to D622N001-9 (September 2020) 757 MPD document, Section 9, AWLs and CMRs 757-300 with Blended Winglets FAA STC NUMBER ST01518SE AND EASA STC NUMBER 10015659, Revision August 2022. This material specifies airworthiness limitations for structural inspections, structural safe life parts, systems, and certification maintenance requirements. The FAA also reviewed Aviation Partners Boeing AP57.2-0604.2-DTR Supplement to D622N001-DTR (October 2018) 757 Damage Tolerance Rating (DTR) Check Form Document for Boeing 757-200 with Winglets FAA STC NUMBER ST01518SE AND EASA STC NUMBER 10015659, Revision August 2023; and Aviation Partners Boeing AP57.3-0604.2-DTR Supplement to D622N001-DTR (October 2018) 757 DTR Check Form Document for Boeing 757-300 with Blended Winglets FAA STC NUMBER ST01518SE AND EASA STC NUMBER 10015659, Revision August 2023. This material provides the DTR check forms and the procedure for their use. 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 require revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. This proposed AD would also require sending inspection results to Aviation Partners Boeing. This proposed AD would require revisions to certain operator maintenance documents to include new actions ( <E T="03">e.g.,</E> inspections). Compliance with these actions is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by this proposed AD, the operator may not be able to accomplish the actions described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request a ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 25k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━