Airworthiness Directives; Airbus SAS Airplanes

<RULE> DEPARTMENT OF TRANSPORTATION <SUBAGY>Federal Aviation Administration</SUBAGY> <CFR>14 CFR Part 39</CFR> <DEPDOC>[Docket No. FAA-2025-1731; Project Identifier MCAI-2025-00491-T; Amendment 39-23109; AD 2025-16-11]</DEPDOC> <RIN>RIN 2120-AA64</RIN> <SUBJECT>Airworthiness Directives; Airbus SAS 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 adopting a new airworthiness directive (AD) for all Airbus SAS Model A321-271NY airplanes. This AD was prompted by the determination that affected parts addressed by other ADs could be installed in service on this airplane model. This AD requires corrective action if necessary and prohibits the installation of affected parts. The FAA is issuing this AD to address unsafe conditions on these products. </SUM> <EFFDATE> <HD SOURCE="HED">DATES:</HD> This AD is effective September 2, 2025. The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of September 2, 2025. The FAA must receive comments on this AD by October 2, 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-2025-1731; 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, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. <E T="03">Material Incorporated by Reference:</E> • For European Union Aviation Safety Agency (EASA) material identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email <E T="03">ADs@easa.europa.eu.</E> You may find this material on the EASA website at <E T="03">ad.easa.europa.eu.</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-2025-1731. <FURINF> <HD SOURCE="HED">FOR FURTHER INFORMATION CONTACT:</HD> Dan Rodina, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3225; email: <E T="03">Dan.Rodina@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 data, views, or arguments about this final rule. Send your comments using a method listed under the <E T="02">ADDRESSES</E> section. Include “Docket No. FAA-2025-1731; Project Identifier MCAI-2025-00491-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 Dan Rodina, Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 206-231-3225; email: <E T="03">Dan.Rodina@faa.gov.</E> Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. <HD SOURCE="HD1">Background</HD> EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2025-0075R1, dated July 21, 2025 (EASA AD 2025-0075R1) (also referred to as “the MCAI”), to correct unsafe conditions for all Model A321-271NY airplanes. The MCAI states that EASA issued several ADs to address various possible unsafe conditions. Those EASA ADs include requirements to prohibit installation of affected parts ( <E T="03">i.e.,</E> certain overheat detection system (OHDS) sensing elements, SafeLav gaseous oxygen containers (SLOGCs), chemical oxygen generators, and trimmable horizontal stabilizer actuators (THSAs)) on Model A321 series airplanes (among other models). Since those EASA ADs were issued, a new airplane model, A321-271NY, has been certified, on which the affected parts could be installed in service. The FAA is issuing this AD to address the following unsafe conditions: • OHDS sensing elements that do not properly detect thermal bleed leak events. This unsafe condition, if not addressed, could result in an air leak remaining undetected by the OHDS at an affected position and not being isolated during flight, possibly resulting in localized areas of the main landing gear bay and keel beam being exposed to high temperatures and consequent reduced structural integrity of the airplane. • Missing heat treatment of the actuation pin of the SLOGC, which could cause its jamming, with consequent failure of oxygen flow activation. This unsafe condition, if not addressed, could result in lack of supplemental oxygen supply in case of decompression in the cabin/lavatory, possibly resulting in injury to lavatory occupants. • Poor reactivity of the start powder used inside the affected oxygen generators. This unsafe condition, if not addressed, could lead to a reduction of the available oxygen capacity of the airplane and could result in injury to airplane occupants. • Improper installation of the THSA ball screw jack, which can compromise the failsafe design of the THSA. This unsafe condition, if not addressed, could result in uncontrolled movement of the horizontal stabilizer as a result of a single failure of the THSA and consequent loss of control of the airplane. • Erroneous accumulated life information in the THSA release certificate, which could lead to operation of the THSA beyond the certificated life limit. This unsafe condition, if not addressed, could result in failure of the THSA and consequent reduced controllability of the airplane. You may examine the MCAI in the AD docket at <E T="03">regulations.gov</E> under Docket No. FAA-2025-1731. <HD SOURCE="HD1">Material Incorporated by Reference Under 1 CFR Part 51</HD> The FAA reviewed EASA AD 2025-0075R1, which specifies procedures for obtaining approved instructions if an affected part is installed and prohibits installation of affected parts. 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">FAA's Determination</HD> These products have been approved by the civil aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, that authority has notified the FAA of the unsafe condition described in the MCAI referenced above. The FAA is issuing this AD 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">Requirements of This AD</HD> This AD requires accomplishing the actions specified in EASA AD 2025-0075R1 described previously, except for any differences identified as exceptions in the regulatory text of this AD. <HD SOURCE="HD1">Explanation of Required Compliance Information</HD> In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some civil aviation authority (CAA) ADs as the primary source of information for compliance with requirements for corresponding FAA ADs. The FAA has been coordinating this process with manufacturers and CAAs. As a result, EASA AD 2025-0075R1 is incorporated by reference in this AD. This AD requires compliance with EASA AD 2025-0075R1 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this AD. Using common terms that are the same as ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Preview showing 10k of 21k characters. Full document text is stored and available for version comparison. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━