Airworthiness Directives; The Boeing Company Airplanes

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-5031; Project Identifier AD-2025-01681-T; Amendment 39-23203; AD 2025-23-53]</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> Final rule; request for comments. <SUM> <HD SOURCE="HED">SUMMARY:</HD> The FAA is superseding Emergency Airworthiness Directive (AD) 2025-23-51, which applied to all The Boeing Company Model MD-11 and MD-11F airplanes. Emergency AD 2025-23-51 was prompted by an accident where the left-hand engine and pylon detached from the airplane during takeoff. Emergency AD 2025-23-51 prohibited further flight until the airplane is inspected and all applicable corrective actions are performed using a method approved by the FAA. Since the FAA issued Emergency AD 2025-23-51, the FAA has determined additional airplane models are subject to the same unsafe condition. This emergency AD continues to require the actions in AD 2025-23-51 and adds the Model MD-10-10F, MD-10-30F, DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, and DC-10-40F airplanes to the applicability. The FAA previously sent an emergency AD to all known U.S. owners and operators of these airplanes. The FAA is issuing this emergency AD to address the unsafe condition on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This AD is effective on December 1, 2025. Emergency AD 2025-23-53, issued on November 14, 2025, which contains the requirements of this amendment, was effective with actual notice. The FAA must receive comments on this AD by January 8, 2026. </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> by searching for and locating Docket No. FAA-2025-5031; 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 final rule, any comments received, and other information. The street address for Docket Operations is listed above. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Brian Knaup, Manager, AIR-520, Continued Operational Safety Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 817-222-5390; email: <E T="03">OperationalSafety@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 AD. Send your comments using a method listed under the <E T="02">ADDRESSES</E> section. Include “Docket No. FAA-2025-5031; Project Identifier AD-2025-01681-T” at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, 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 final rule 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 final rule. <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 AD 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 AD, 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 AD. Submissions containing CBI should be sent to Brian Knaup, Manager, AIR-520, Continued Operational Safety Branch, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 817-222-5390; email: <E T="03">OperationalSafety@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 Emergency AD 2025-23-51, on November 8, 2025 (Emergency AD 2025-23-51), to address an unsafe condition on all The Boeing Company Model MD-11 and MD-11F airplanes. The FAA sent the emergency AD to all known U.S. owners and operators of these airplanes. Emergency AD 2025-23-51 prohibited further flight until the airplane was inspected and all applicable corrective actions were performed using a method approved by the Manager, AIR-520, Continued Operational Safety Branch, FAA. Emergency AD 2025-23-51 was prompted by an accident where the left-hand engine and pylon detached from the airplane during takeoff. The cause of the detachment is currently under investigation. This condition could result in loss of continued safe flight and landing. The FAA published the <E T="04">Federal Register</E> version of Emergency AD 2025-23-51, Amendment 39-23193, on November 14, 2025 (90 FR 51019). <HD SOURCE="HD1">Actions Since Emergency AD 2025-23-51 Was Issued</HD> Since the FAA issued Emergency AD 2025-23-51, the FAA has determined additional airplane models are subject to the same unsafe condition. The engine-pylon structure of the Model MD-11 and MD-11F airplanes is similar in design to that of the Model MD-10-10F, MD-10-30F, DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, and DC-10-40F airplanes. The FAA, therefore, is superseding Emergency AD 2025-23-51 to add these additional airplane models to the applicability of this emergency AD. <HD SOURCE="HD1">FAA's Determination</HD> The FAA is issuing this emergency AD because the agency has determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. <HD SOURCE="HD1">AD Requirements</HD> This emergency AD prohibits further flight until the airplane is inspected and all applicable corrective actions are performed using a method approved by the Manager, AIR-520, Continued Operational Safety Branch, FAA. <HD SOURCE="HD1">Interim Action</HD> The FAA considers this emergency AD to be an interim action. If final action is later identified, the FAA might consider further rulemaking then. <HD SOURCE="HD1">FAA's Justification and Determination of the Effective Date</HD> Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 <E T="03">et seq.</E> ) authorizes agencies to forgo notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause. An unsafe condition exists that required the immediate adoption of Emergency AD 2025-23-53 issued on November 14, 2025, to all known U.S. owners and operators of these airplanes. The FAA found that the risk to the flying public and safety in air commerce justified forgoing notice and comment prior to adoption of this rule because the severity of the unsafe condition necessitates prohibiting further flight until the airplane is inspected and the applicable corrective actions are performed. These conditions still exist, and the AD is hereby published in the <E T="04">Federal Register</E> as an amendment to 14 CFR 39.13 to make it effective to all persons. Given the significance of the risk presented by this unsafe condition, it must be immediately addressed. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b). In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forgo notice and comment. <HD SOURCE="HD1">Regulatory Flexibility Act (RFA)</HD> The requirements of the RFA do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because the FAA has determined that it has good cause to adopt this rule without notice and comment, RFA analysis is not required. <HD SOURCE="HD1">Costs of Compliance</HD> The FAA estimates that this emergency AD affects 167 airplanes of U.S. registry. The FAA has no definitive data on which to base the cost estimates for the inspection and corrective actions specified in this emergency AD. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 17k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━