# [Amended]
**AGENCY:**
Federal Aviation Administration (FAA), DOT.
**ACTION:**
Notice of proposed rulemaking (NPRM).
**SUMMARY:**
The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus Helicopters Model H160-B helicopters. This proposed AD was prompted by a report of a tail rotor drive rear shaft that came into contact with its rear damper during a flight test. This proposed AD would require repetitive visual inspections of the rear damper and, depending on the results, corrective actions. The FAA is proposing this AD to address the unsafe condition on these products.
**DATES:**
The FAA must receive comments on this NPRM by January 12, 2026.
**ADDRESSES:**
You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:
• *Federal eRulemaking Portal:* Go to *regulations.gov.* Follow the instructions for submitting comments.
• *Fax:* (202) 493-2251.
• *Mail:* U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.
• *Hand Delivery:* Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.
*AD Docket:* You may examine the AD docket at *regulations.gov* under Docket No. FAA-2025-5033; 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, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above.
*Material Incorporated by Reference:*
• For European Union Aviation Safety Agency (EASA) material identified in this proposed AD, contact EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; phone: +49 221 8999 000; email: *[email protected];* website: *easa.europa.eu.* You may find the EASA material on the EASA website at *ad.easa.europa.eu.*
• 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.
**FOR FURTHER INFORMATION CONTACT:**
Adam Hein, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 946-4116; email: *[email protected].*
**SUPPLEMENTARY INFORMATION:**
**Comments Invited**
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 *ADDRESSES* section. Include “Docket No. FAA-2025-5033; Project Identifier MCAI-2025-00795-R” 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 *regulations.gov,* including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.
**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 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 Adam Hein, 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 2025-0098, dated April 29, 2025 (EASA AD 2025-0098) (also referred to as the MCAI), to correct an unsafe condition on Airbus Helicopters Model H160-B helicopters. The MCAI advises of a report that the tail rotor drive rear shaft of the tail drive line had come in contact with its rear damper during a flight test. This contact is expected only when the helicopter is on the ground, during transition phases of either accelerating (ramp up) or decelerating (ramp-down), when passing the shaft critical mode. This unsafe condition, if not detected and corrected, could result in degradation of the rear damper and its support, loss of the rear damper function, failure of the tail rotor drive rear shaft, and consequent loss of yaw control of the helicopter.
You may examine the MCAI in the AD docket at *regulations.gov* under Docket No. FAA-2025-5033.
**Material Incorporated by Reference Under 1 CFR Part 51**
The FAA reviewed EASA AD 2025-0098, which specifies procedures for repetitive visual inspections of the two radii in the top area of the rear damper, the hard chrome oxide deposit on the friction bush located under the rear damper, and the rear damper supports for cracks and loose or missing fasteners and, depending on the results, performing further inspections, replacing the rear damper, or contacting the manufacturer for further corrective actions. 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 NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.
**Proposed AD Requirements in This NPRM**
This proposed AD would require accomplishing the actions specified in EASA AD 2025-0098, described previously, as incorporated by reference, except for any differences identified as exceptions in the regulatory text of this proposed AD. See “Differences Between this Proposed AD and the MCAI” for a discussion of the general differences included in this AD.
**Differences Between This Proposed AD and the MCAI**
Where the MCAI specifies contacting Airbus Helicopters for repair instructions, this proposed AD would require using a method approved by the FAA, EASA, or Airbus Helicopters' EASA Design Organization Approval.
**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, the FAA proposes to incorporate EASA AD 2025-0098 by reference in the FAA final rule. This proposed AD would, therefore, require compliance with EASA AD 2025-0098 in its entirety through that incorporation, except for any differences identified as exceptions in the regulatory text of this proposed AD. Using common terms that are the same as the heading of a particular section in EASA AD 2025-0098 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 2025-0098. Material required by EASA AD 2025-0098 for compliance will be available at *regulations.gov* under Docket No. FAA-2025-5033 after the FAA final rule is published.
**Costs of Compliance**
The FAA estimates that this AD, if adopted as proposed, would affect nine helicopters of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:
| Action | Labor cost | Parts cost | Cost per | Cost on U.S. |
| --- | --- | --- | --- | --- |
| Visual inspection of rear damper | 1 work-hour × $85 per hour = $85 | $0 | $85 | $765 |
The FAA estimates the following costs to do any replacements that would be required based on the results of the proposed inspection. The agency has no way of determining the number of helicopters that might need these replacements:
| Action | Labor cost | Parts cost | Cost per product |
| --- | --- | --- | --- |
| Replace rear damper | 8 work-hours × $85 per hour = $680 | $22,647 | $23,327 |
The FAA has received no definitive data on which to base the cost estimates for the corrective actions specified in this proposed AD.
**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**
The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 this proposed regulation:
(1) Is not a “significant regulatory action” under Executive Order 12866,
(2) Would not affect intrastate aviation in Alaska, and
(3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.
**List of Subjects in 14 CFR Part 39**
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
**The Proposed Amendment**
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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
2. The FAA amends § 39.13 by adding the following new airworthiness directive:
*Airbus Helicopters:* Docket No. FAA-2025-5033; Project Identifier MCAI-2025-00795-R.
**(a) Comments Due Date**
The FAA must receive comments on this airworthiness directive (AD) by January 12, 2026.
**(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 6510, Tail Rotor Drive Shaft.
**(e) Unsafe Condition**
This AD was prompted by a report of a tail rotor drive rear shaft of the tail drive line coming into contact with its rear damper during a flight test. The FAA is issuing this AD to detect and correct the tail rotor drive rear shaft contacting the rear damper during flight. The unsafe condition, if not addressed, could result in degradation of the rear damper and its support, loss of the rear damper function, failure of the tail rotor drive rear shaft, and consequent loss of yaw control of the helicopter.
**(f) Compliance**
Comply with this AD within the compliance times specified, unless already done.
**(g) Required Actions**
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 2025-0098, dated April 29, 2025 (EASA AD 2025-0098).
**(h) Exceptions to EASA AD 2025-0098**
(1) Where EASA AD 2025-0098 refers to its effective date, this AD requires using the effective date of this AD.
(2) Where EASA AD 2025-0098 requires compliance in terms of flight hours, this AD requires using hours time-in-service.
(3) Where paragraph (2) of EASA AD 2025-0098 specifies contacting AH (Airbus Helicopters) to obtain approved instructions, this AD requires actions done in accordance with a method approved by the Manager, International Validation Branch, FAA; or EASA; or Airbus Helicopters' EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.
(4) This AD does not adopt the “Remarks” section of EASA AD 2025-0098.
**(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: *[email protected].*
(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 Adam Hein, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (316) 946-4116; email: *[email protected].*
**(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 2025-0098, dated April 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: *[email protected];* 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 *[email protected].*
Issued on November 24, 2025.
Steven W. Thompson,
Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.