2025-11665: Airworthiness Directives; Safran Helicopter Engines

Federal Register, Volume 90 Issue 120 (Wednesday, June 25, 2025) [Federal Register Volume 90, Number 120 (Wednesday, June 25, 2025)] [Proposed Rules] [Pages 26950-26951] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2025-11665] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA-2025-0341; Product Identifier MCAI-2024-00679-E] RIN 2120-AA64 Airworthiness Directives; Safran Helicopter Engines

Agency

Federal Aviation Administration (FAA), DOT.

Action

Notice of proposed rulemaking (NPRM); withdrawal. -----------------------------------------------------------------------

Summary

The FAA is withdrawing an NPRM that proposed to adopt a new airworthiness directive (AD) that would have applied to all Safran Helicopter Engines, S.A. (Safran) Model ARRIUS 2F and ARRIUS 2R engines. The NPRM was prompted by a manufacturer investigation that revealed certain high-pressure (HP) turbine blades may contain non- compliant porosity rates due to a change in the manufacturing process. The NPRM would have required replacement of affected HP turbine blades. Since the NPRM was issued, further investigation and tests demonstrated that the non-compliant rate of porosity has no impact on the use limit of the affected parts and the FAA has determined that the unsafe condition no longer exists. Accordingly, the NPRM is withdrawn.

Dates

As of June 25, 2025, the proposed rule, which was published in the Federal Register on March 13, 2025 (90 FR 11914), is withdrawn.

Addresses

You may examine the AD docket at regulations.gov under Docket No. FAA-2025-0341; or in person at the Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD action (withdrawal), the NPRM, the mandatory continuing airworthiness information, any comments received, and other information. The street 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.

For Further Information Contact

David Bergeron, Aerospace Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (781) 238-7157; email: [email protected].

Supplementary Information

Discussion Background The FAA issued an NPRM that proposed to amend 14 CFR part 39 by adding an AD for all Safran Model ARRIUS 2F and ARRIUS 2R engines. The NPRM was published in the Federal Register on March 13, 2025 (90 FR 11914). The NPRM was prompted by a manufacturer investigation that revealed certain HP turbine blades may contain non-compliant porosity rates due to a change in the manufacturing process. The NPRM proposed to require replacement of affected HP turbine blades, as specified in European Union Aviation Safety Agency (EASA) AD 2024-0218R1, dated December 19, 2024 (EASA AD 2024-0218R1). The proposed actions were intended to prevent the failure of the HP turbine blades. The unsafe condition, if not addressed, could result in an in-flight shutdown and a significant reduction in the control of the helicopter. Actions Since the NPRM Was Issued Since issuance of the NPRM, EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2024- 0218R1-CN, dated March 17, 2025 (EASA AD 2024- [[Page 26951]] 0218R1-CN), which cancels EASA AD 2024-0218R1. EASA AD 2024-0218R1-CN states that since EASA AD 2024-0218R1 was issued, further investigation and tests demonstrated that the non-compliant rate of porosity has no impact on the use limit of the affected parts, and the subsequent risk re-assessment has shown that the safety issue addressed by the previous EASA AD does not qualify as an unsafe condition. Therefore, the FAA has determined that AD action is no longer appropriate. Withdrawal of the NPRM constitutes only such action and does not preclude the FAA from further rulemaking on this issue, nor does it commit the FAA to any course of action in the future. Comments The FAA received comments from two commenters, including Summit Helicopters, Inc. and an anonymous commenter. The following presents the comments received on the NPRM and the FAA's response to each comment. Request for Clarification Dependent on Issuance of New EASA AD Summit Helicopers, Inc. requested that the FAA either cancel the NPRM or revise to remove reference to EASA AD 2024-0218R1. Summit Helicopters, Inc. pointed out that EASA has issued EASA AD 2024-0218R1- CN, which cancelled EASA AD 2024-0218R1. The FAA agrees with the request and is withdrawing the NPRM. Request for Greater Oversight of, and Transparency From, the Manufacturer An anonymous commenter discussed numerous topics affecting the NPRM, especially requesting that the FAA require greater oversight of, and transparency from, the engine manufacturer. Additional topics included specialized training for technicians, environmental considerations, emergency preparedness, publication of root cause analysis reports, cost burden for operators, health and safety standards and equipment, and alignment of future oversight with international best practices and quality management standards. The FAA agrees that all the discussed topics may have had an impact should the NPRM have continued to become a final rule. However, because the NPRM is withdrawn, the discussion and requests are no longer necessary. FAA's Conclusions Upon further consideration, the FAA has determined that the NPRM is unnecessary. Accordingly, the NPRM is withdrawn. Regulatory Findings Since this action only withdraws an NPRM, it is neither a proposed nor a final rule and therefore is not covered under Executive Order 12866, the Regulatory Flexibility Act, or DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Withdrawal Accordingly, the notice of proposed rulemaking (Docket No. FAA- 2025-0341), which was published in the Federal Register on March 13, 2025 (90 FR 11914), is withdrawn. Issued on June 18, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025-11665 Filed 6-24-25; 8:45 am] BILLING CODE 4910-13-P