Comments Invited 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 ADDRESSES section. Include "Docket No. FAA-2025-3431; Project Identifier MCAI-2025-01291-R" 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 regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule. 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 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 Margot Perez Sosa, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2025-0165, dated July 29, 2025 (EASA AD 2025-0165) (also referred to as the MCAI), to correct an unsafe condition on Airbus Helicopters Model H160-B helicopters. The MCAI states a report of the MGB RH center and rear rail support assemblies were found broken. Additionally, after further inspections, the square bearings were also found broken. The FAA is issuing this AD to prevent failure of the MGB support assemblies. The unsafe condition, if not addressed, could result in loss of the cowling in-flight, which could cause an impact with the main rotor blades and could result in a loss of control of the helicopter. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2025-3431. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed EASA AD 2025-0165, which specifies procedures for repetitively inspecting the MGB center and rear rail supports and the correspondent square housing bearings and, depending on the results of these inspections, replacing the center rail support, the rear rail support, or the square housing bearing. 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 ADDRESSES section. FAA's Determination These products have been approved by the civil aviation authority (CAA) 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. AD Requirements This AD requires accomplishing the actions specified in EASA AD 2025-0165, described previously, except for any differences identified as exceptions in the regulatory text of this AD. Explanation of Required Compliance Information In the FAA's ongoing efforts to improve the efficiency of the AD process, the FAA developed a process to use some 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 2025-0165 is incorporated by reference in this AD. This AD requires compliance with EASA AD 2025-0165 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 the heading of a particular section in EASA AD 2025-0165 does not mean that operators need comply only with that section. For example, where the AD requirement refers to "all required actions and compliance times," compliance with this AD requirement is not limited to the section titled "Required Action(s) and Compliance Time(s)" in EASA AD 2025-0165. Material required by EASA AD 2025-0165 for compliance will be available at regulations.gov under Docket No. FAA-2025-3431 after this AD is published. Justification for Immediate Adoption and Determination of the Effective Date Section 553(b) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq. ) authorizes agencies to dispense with 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 requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies forgoing notice and comment prior to adoption of this because the failure of the MGB center support could lead to loss of the cowling in flight and consequently cause an impact with the main rotor blades, which could lead to loss of control of the helicopter. For this reason, depending on the condition of your helicopter, the initial actions required by this AD must be accomplished within 55 hours time-in-service, which is shorter than the time necessary for the public to comment and for publication of the final rule. 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. Regulatory Flexibility Act The requirements of the Regulatory Flexibility Act (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 prior notice and comment, RFA analysis is not required. Costs of Compliance The FAA estimates that this AD affects 12 helicopters of U.S. registry. The FAA estimates the following costs to comply with this AD. Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators Inspect center rail supports 0.50 work-hours × $85 per hour = $42.50 $0 $42.50 $510 The FAA estimates the following costs to do any necessary replacements that would be required based on the results of the inspection. The agency has no way of determining the number of helicopters that might need these replacements. On-Condition Costs Action Labor cost Parts cost Cost per product Replace LH center rail support 1 work-hour × $85 per hour = $85 $4,537 $4,622 Replace LH rear rail support 1 work-hour × $85 per hour = $85 2,063 2,148 Replace square housing bearing 0.25 work-hours × $85 per hour = $21.25 132 153.25 Replace RH center rail support 1 work-hour × $85 per hour = $85 4,537 4,622 Replace RH rear rail support 1 work-hour × $85 per hour = $85 2,063 2,148 Authority for This Rulemaking Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs describes in more detail the scope of the Agency's authority. The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify that this AD: (1) Is not a "significant regulatory action" under Executive Order 12866, and (2) Will not affect intrastate aviation in Alaska. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39-AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2025-20-17 Airbus Helicopters: Amendment 39-23170; Docket No. FAA-2025-3431; Project Identifier MCAI-2025-01291-R. (a) Effective Date This airworthiness directive (AD) is effective October 30, 2025. (b) Affected ADs None. (c) Applicability This AD applies to Airbus Helicopters Model H160-B helicopters, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 5320, Fuselage Miscellaneous Structure. (e) Unsafe Condition This AD was prompted by a report of broken main gearbox (MGB) right hand (RH) center and rear rail support assemblies. The FAA is issuing this AD to prevent failure of the MGB support assemblies. The unsafe condition, if not addressed, could result in loss of the cowling in-flight, which could cause an impact with the main rotor blades and could result in a loss of control of the helicopter. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Requirements Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2025-0165, dated July 29, 2025 (EASA AD 2025-0165). (h) Exceptions to EASA AD 2025-0165 (1) Where EASA AD 2025-0165 refers to its effective date, this AD requires using the effective date of this AD. (2) Where EASA AD 2025-0165 requires compliance in terms of flight hours, this AD requires using hours time-in-service. (3) Where EASA AD 2025-0165 specifies "Flight Hours" in the column heading of Table 1, this AD requires replacing that text with "Hours time-in-service as of the effective date of this AD". (4) Where the material referenced in EASA AD 2025-0165 specifies "if necessary, clean the square housing bearing", this AD requires replacing that text with "clean the square housing bearing". (5) Where the material referenced in EASA AD 2025-0165 specifies to install a "new" part, this AD requires replacing that text with "new (never installed)" part. (6) Where the material referenced in EASA AD 2025-0165 specifies to discard certain parts, this AD requires removing those parts from service. (7) This AD does not adopt the "Remarks" section of EASA AD 2025-0165. (i) Alternative Methods of Compliance (AMOCs) (1) The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. (j) Additional Information For more information about this AD, contact Margot Perez Sosa, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 941-1287; email: margot.i.perez.sosa@faa.gov. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this material as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) European Union Aviation Safety Agency (EASA) AD 2025-0165, dated July 29, 2025. (ii) [Reserved] (3) For EASA material identified in this AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: ADs@easa.europa.eu; website: easa.europa.eu. You may find the EASA material on the EASA website at ad.easa.europa.eu. (4) You may view this material at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Parkway, Room 6N-321, Fort Worth, TX 76177. For information on the availability of this material at the FAA, call (817) 222-5110. (5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov. Issued on October 9, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.