2026-02-04: Turbine Engine Compressor Section

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2026-02-04 CFM International, S.A.: Amendment 39-23240; Docket No. FAA-2025-1115; Project Identifier AD-2024-00797-E. (a) Effective Date This airworthiness directive (AD) is effective February 26, 2026. (b) Affected ADs None. (c) Applicability This AD applies to CFM International, S.A. (CFM) Model LEAP-1A23, LEAP-1A24, LEAP-1A24E1, LEAP-1A26, LEAP-1A26CJ, LEAP-1A26E1, LEAP-1A29, LEAP-1A29CJ, LEAP-1A30, LEAP-1A32, LEAP-1A33, LEAP-1A33B2, and LEAP-1A35A engines with an installed No. 3 bearing spring finger housing having part number (P/N) 2629M62G01 and a serial number identified in Table 1 of CFM Service Bulletin (SB) LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, dated September 24, 2025 (CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00). (d) Subject Joint Aircraft System Component (JASC) Code 7230, Turbine Engine Compressor Section. (e) Unsafe Condition This AD was prompted by a report of multiple aborted takeoffs and air turn-backs caused by high-pressure compressor (HPC) stall, which was induced by high levels of non-synchronous vibration (NSV), and an additional manufacturer investigation that revealed wear on the No. 3 bearing spring finger housing. The FAA is issuing this AD to prevent HPC stall. The unsafe condition, if not addressed, could result in engine power loss at a critical phase of flight such as takeoff or climb, loss of engine thrust control, reduced controllability of the airplane, and loss of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions (1) Within 50 flight cycles (FCs) after the effective date of this AD and thereafter at intervals not to exceed 50 FCs, calculate the NSV data in accordance with the Accomplishment Instructions, paragraphs 5.A.(1) and 5.A.(3), or 5.B.(1) and 5.B.(3) of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00. (2) If, during any calculation required by paragraph (g)(1) of this AD, the NSV data exceeds the limits specified in the Accomplishment Instructions paragraph 5.A.(4)(a)1, 5.A.(4)(a)2, or 5.B.(4)(a)1 of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, discontinue the calculations required by paragraph (g)(1) of this AD and within 25 FCs or 5 FCs, as applicable to the threshold exceeded, of the flight when these limits are exceeded: (i) Remove from service the No. 3 bearing spring finger housing having P/N 2629M62G01 and a serial number identified in Table 1 of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, and replace with a part eligible for installation. (ii) Inspect the stage 2 high-pressure turbine (HPT) nozzle assembly honeycomb for rubs in accordance with the Accomplishment Instructions, paragraphs 5.A.(4)(a)4b or 5.B.(4)(a)3b of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00. (iii) Inspect the HPT stator stationary seal honeycomb for rubs in accordance with the Accomplishment Instructions, paragraphs 5.A.(4)(a)4b or 5.B.(4)(a)3b of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00. (3) If, during the inspection required by paragraph (g)(2)(ii) of this AD, the stage 2 HPT nozzle assembly honeycomb fails to meet the serviceability criteria referenced in the Accomplishment Instructions, paragraphs 5.A.(4)(a)4b or 5.B.(4)(a)3b of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, before further flight, replace the stage 2 HPT nozzle assembly honeycomb. (4) If, during the inspection required by paragraph (g)(2)(iii) of this AD, the HPT stator stationary seal honeycomb fails to meet the serviceability criteria referenced in the Accomplishment Instructions, paragraphs 5.A.(4)(a)4b or 5.B.(4)(a)3b of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, before further flight, replace the HPT stator stationary seal. (5) At the next shop visit after the effective date of this AD, perform the following: (i) Replace the No. 3 bearing spring finger housing having P/N 2629M62G01 and a serial number identified in Table 1 of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, with a part eligible for installation in accordance with paragraph 5.A.(1) of CFM SB LEAP-1A-72-00-0536-01A-930A-D, Issue 001-00, dated July 22, 2024 (CFM SB LEAP-1A-72-00-0536-01A-930A-D, Issue 001-00); and, (ii) Inspect the stage 2 HPT nozzle assembly honeycomb and the HPT stator stationary seal honeycomb for rubs and disposition in accordance with paragraph 5.B.(4) and 5.B.(5) of CFM SB LEAP-1A-72-00-0536-01A-930A-D, Issue 001-00. (h) Terminating Action Replacement of the No. 3 bearing spring finger housing having P/N 2629M62G01 and a serial number identified in Table 1 of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00 with a part eligible for installation, as specified in paragraph (g)(2)(i) and (g)(5) of this AD, constitutes terminating action for the calculations required by paragraph (g)(1) of this AD. (i) Definitions (1) For the purpose of this AD, a "part eligible for installation" is a No. 3 bearing spring finger housing that does not have P/N 2629M62G01 and a serial number identified in Table 1 of CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00. (2) For the purpose of this AD, a "shop visit" is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges, except that the separation of engine flanges solely for the purposes of transportation without subsequent engine maintenance does not constitute an engine shop visit. (j) Credit for Previous Actions You may take credit for the actions required by paragraphs (g)(1) through (4) and (h) of this AD if you performed these actions before the effective date of this AD using CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 001-00, dated April 30, 2025. (k) Alternative Methods of Compliance (AMOCs) (1) The Manager, AIR-520 Continued Operational Safety 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, AIR-520 Continued Operational Safety Branch, send it to the attention of the person identified in paragraph (l) 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. (3) For service material that contains steps that are labeled as Required for Compliance (RC), the following provisions apply. (i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, that are required by paragraph (g) of this AD must be done to comply with this AD. An AMOC is required for any deviations to RC steps required by paragraph (g) of this AD, including substeps and identified figures. (ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator's maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. (l) Additional Information (1) For more information about this AD, contact Mehdi Lamnyi, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: (781) 238-7743; email: [email protected]. (2) For CFM material, which is not incorporated by reference in this AD, contact CFM, GE Aviation Fleet Support, 1 Neumann Way, M/D Room 285, Cincinnati, OH 45215; phone: (877) 432-3272; email: [email protected]. (m) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) 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) CFM International, S.A. (CFM) Service Bulletin (SB) LEAP-1A-72-00-0536-01A-930A-D, Issue 001-00, dated July 22, 2024. (ii) CFM SB LEAP-1A-72-00-0562-01A-930A-D, Issue 002-00, dated September 24, 2025. (3) For CFM material identified in this AD, contact CFM, GE Aviation Fleet Support, 1 Neumann Way, M/D Room 285, Cincinnati, OH 45215; phone: (877) 432-3272; email: [email protected]. (4) You may view this material at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. 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 January 13, 2026. Peter A. White, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2026-01152 Filed 1-21-26; 8:45 am]BILLING CODE 4910-13-P