AD 2025-25-06

This AD is effective February 6, 2026.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of February 6, 2026.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2025-0612; 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 address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

Material Incorporated by Reference:

• For European Union Aviation Safety Agency (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 this 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. It is also available at regulations.gov under Docket No. FAA-2025-0612.

Zain Jamal, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (847) 294-7264; email: zain.jamal@faa.gov.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Airbus Helicopters Model SA341G and SA342J helicopters. The NPRM was published in the Federal Register on April 7, 2025 (90 FR 14922). The NPRM was prompted by AD 2023-0155, dated July 31, 2023 (EASA AD 2023-0155) (also referred to as the MCAI), issued by EASA, which is the Technical Agent for the Member States of the European Union. The MCAI states that reports were received of the stainless steel leading edge protection disbonding on certain part-numbered MRBs. This condition, if not detected and addressed, could result in significant unbalance of the main rotor, a high level of vibration, failure of the main rotor and main gearbox, and consequent loss of control of the helicopter.

In the NPRM, the FAA proposed to require repetitively tap inspecting the MRB and, depending on the results, repairing or replacing the MRB. In the NPRM, the FAA also proposed to prohibit installing those MRB unless certain requirements are met. The FAA is issuing this AD to address the unsafe condition on these products.

You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2025-0612.

The FAA received comments from an anonymous commenter who requested the FAA take into consideration the community, operator, and environmental impact when issuing an AD. The commenter made several other comments not specific to this AD, such as systemic and social-justice recommendations, which were out of scope of this AD. The following presents the comments received on the NPRM and the FAA's response to the comments.

The commenter requested the FAA consider using a tiered or risk-based inspection interval for low-utilization or community-serving operators. The commenter also requested that the FAA provide guidance for financial assistance to those disproportionally affected by ADs. The commenter stated that MRB inspections and MRB repair or replacement impose substantial labor and financial costs, especially on small operators and public sector agencies. The commenter requested the FAA consider cost offsets or grants for public-benefit entities.

The FAA disagrees with the commenter. The NPRM requires a tap inspection, which takes an hour to complete. The FAA is issuing this AD to address an unsafe condition on the Airbus Helicopters Model SA341G and SA342J helicopters. Changing the inspection interval for low-utilization operators or public sector agencies does not address this unsafe condition because the FAA would be allowing higher risk to the flying public by allowing low-utilization operators or public sector agencies to have different inspection intervals that could allow the unsafe condition to remain on the helicopter for an unacceptable amount of time. The NPRM originally included the cost to replace these blades at $168,449 per blade. However, FAA revised the estimated cost of this final rule to reflect the repair cost, since it was determined that most operators have elected to repair their blades instead of replacing them with new blades. The repair cost is significantly less burdensome than the replacement cost and would not impose substantial labor and financial costs on small operators and public sector agencies.

Additionally, the FAA is unable to offer guidance on financial assistance for those impacted by this AD because that is outside the scope of an FAA AD response. No changes were made to this AD as a result of this comment.

The commenter requested that all inspections and repairs be done by a unionized or properly certified mechanic. The commenter stated the FAA should require transparency in labor practices and support ongoing worker safety training.

The FAA acknowledges the commenter's concern. FAA regulations stipulate who can perform AD related inspections and repairs on U.S.-registered aircraft. No changes were made to this AD as a result of this comment.

The commenter requested that critical service operators ( e.g., air ambulances, disaster relief) should have temporary compliance waivers or rapid repair authorizations when public safety is at stake, with oversight to prevent abuse.

The FAA acknowledges the commenter's concern. An operator can request an alternative method of compliance (AMOC) for relief by using the process in paragraph (j) of this AD. No changes were made to this AD as a result of this comment.

The commenter requested that the FAA require reporting and public disclosure of inspection findings, repairs, and failures, broken down by operator type and geography, to foster accountability and help communities advocate for safer air transport.

The FAA partially agrees. For Part 121 operators, reports of certain failure, malfunction, or defect can be submitted and searched on the service difficulty reporting (SDR) system site. The FAA-EASA Technical Implementation Procedures (TIP) define the ongoing obligations of both authorities to share relevant airworthiness and safety-related information. Under the TIP, the FAA and EASA have developed procedures to exchange data on airworthiness standards, certification systems, and emerging safety concerns; identify and evaluate safety issues early; and agree on actions to address those concerns in order to maintain continued confidence in each other's systems. Findings from surveillance and audits are shared, and both parties commit to timely communication of safety and airworthiness information. The commenter's request to require reporting and disclose inspection findings, repairs, and failures to the public goes beyond the FAA-EASA TIP agreement and the scope of this AD. No changes were made to this AD as a result of this comment.

The commenter requested that the FAA assess the environmental impact of increased MRB replacements, especially regarding disposal of hazardous composites and metals. The commenter stated that the FAA should require operators to recycle or safely dispose of MRBs, and encourage development of greener rotor blade materials and repair techniques.

The FAA acknowledges the commenter's concern. However, the FAA advises that this AD allows for operators to either repair or replace the MRB as a corrective action. As stated above, most operators have elected to repair the MRB.

Additionally, in accordance with 14 CFR 39.5, the FAA issues an AD when an unsafe condition exists on an aircraft and the condition is likely to exist or develop in other products of the same type design. Mandating how operators dispose of parts removed from an aircraft does not address the unsafe condition. Further, an AD specifies the actions that must be taken to resolve the unsafe condition. Any actions required beyond that may create an unnecessary burden on operators. No changes were made to this AD as a result of this comment.

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 reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for minor editorial changes, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

The FAA reviewed EASA AD 2023-0155, which specifies procedures for repetitively tap inspecting the stainless steel leading edge protection of the MRB having part number (P/N) 341A11-0040-00, P/N 341A11-0040-01, P/N 341A11-0040-02, P/N 341A11-0040-03 or P/N 341A11-0040-04 for disbonding. If disbonding is found, EASA 2023-0155 specifies repairing or replacing the MRB. EASA AD 2023-0155 also prohibits installing an affected MRB unless certain requirements are met. 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.

The FAA estimates that this AD affects 63 helicopters of U.S. registry. Labor rates are estimated at $85 per hour. Based on these numbers, the FAA estimates the following costs to comply with this AD.

Tap inspecting the MRB for disbonding takes 1 work-hour for an estimated cost of $85 per helicopter and $5,355 for the U.S. fleet, per inspection cycle.

Repair of the MRB takes 1 work-hour and parts cost of $17,500 for an estimated cost of $17,585 per blade.

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.

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,

(2) Will not affect intrastate aviation in Alaska, and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by adding the following new airworthiness directive: