2025-25-07: Turbine 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: 2025-25-07 General Electric Company: Amendment 39-23215; Docket No. FAA-2025-1364; Project Identifier AD-2024-00613-E. (a) Effective Date This airworthiness directive (AD) is effective February 6, 2026. (b) Affected ADs None. (c) Applicability This AD applies to the following General Electric Company (GE) Model engines: (1) GE90-90B and GE90-94B engines with a high pressure turbine (HPT) stage 1 disk having a part number and serial number identified in table 1 to paragraph (c) of this AD installed; and (2) GE90-110B1 and GE90-115B engines with an HPT stage 1 disk or HPT stage 2 disk having a part number and serial number identified in table 1 to paragraph (c) of this AD or Table 1 or Table 2 of GE GE90-100 Service Bulletin (SB) 72-0926, Revision 01, dated December 22, 2023 (GE GE90-100 SB 72-0926, Revision 01), installed. Table 1 to Paragraph ( c )-Affected HPT Stage 1 and 2 Disks Part name Part No. Serial No. HPT Stage 1 Disk 1847M95G01 GWN05K5J HPT Stage 1 Disk 1847M95G01 GWN05K5M HPT Stage 1 Disk 1847M95G01 GWN05NP6 HPT Stage 1 Disk 1865M13G08 GWN10N9A HPT Stage 1 Disk 1865M13G07 GWN0NJ92 HPT Stage 1 Disk 1865M13G07 GWN0NJ94 HPT Stage 1 Disk 1865M13G07 GWN0NK87 HPT Stage 1 Disk 1865M13G08 GWN0RJ4G HPT Stage 1 Disk 1865M13G08 GWN0WPEC HPT Stage 2 Disk 1865M14P04 TMT4RK67 HPT Stage 2 Disk 1865M14P04 TMT4RG10 HPT Stage 2 Disk 1865M14P04 TMT4RG11 (d) Subject Joint Aircraft System Component (JASC) Code 7250, Turbine Section. (e) Unsafe Condition This AD was prompted by a manufacturer investigation that revealed certain HPT stage 1 disks and HPT stage 2 disks were manufactured from powder metal material suspected to contain iron inclusion. The FAA is issuing this AD to prevent premature fracture and uncontained failure of the HPT stage 1 disks and HPT stage 2 disks. The unsafe condition, if not addressed, could result in uncontained debris release, damage to the engine, and damage to the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions At the applicable times specified in paragraphs (g)(1) through (3) of this AD, remove each affected HPT stage 1 disk and HPT stage 2 disk from service and replace with a part eligible for installation. (1) For HPT stage 1 disks and HPT stage 2 disks with a part number and serial number identified in table 1 to paragraph (c) of this AD, before further flight. (2) For HPT stage 1 disks with a part number and serial number identified in Table 1 of GE GE90-100 SB 72-0926, Revision 01, that are not identified in table 1 to paragraph (c) of this AD, at the next piece-part exposure or before exceeding 4,650 cycles since new (CSN), whichever occurs first. (3) For HPT stage 2 disks with a part number and serial number identified in Table 2 of GE GE90-100 SB 72-0926, Revision 01, that are not identified in table 1 to paragraph (c) of this AD, at the next piece-part exposure or before exceeding 11,300 CSN, whichever occurs first. (h) Grace Period for HPT Stage 1 Disk Replacement For affected HPT stage 1 disks having greater than 4,650 CSN on the effective date of this AD, the replacement required by paragraph (g)(2) of this AD may be deferred up to 50 flight cycles after the effective date of this AD. (i) Definitions (1) For the purpose of this AD, a "part eligible for installation" is any HPT stage 1 disk or HPT stage 2 disk having a part number and serial number that is not identified in table 1 to paragraph (c) of this AD or Table 1 or Table 2 of GE GE90-100 SB 72-0926, Revision 01. (2) For the purpose of this AD, a "piece-part exposure" is when the affected HPT stage 1 disk or HPT stage 2 disk is removed from the engine and completely disassembled. (j) 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 of AIR-520 Continued Operational Safety Branch, send it to the attention of the person identified in paragraph (k) of this AD and email to: AMOC@faa.gov. 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. (k) Additional Information For more information about this AD, contact Alexei Marqueen, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: (781) 238-7178; email: alexei.t.marqueen@faa.gov. (l) 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) GE GE90-100 Service Bulletin 72-0926, Revision 01, dated December 22, 2023. (ii) [Reserved] (3) For GE material identified in this AD, contact General Electric Company, 1 Neumann Way, Cincinnati, OH 45215; phone: (513) 552-3272; email: aviation.fleetsupport@ge.com; website: ge.com. (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 fr.inspection@nara.gov. Issued on December 8, 2025. Peter A. White, Deputy Director, Integrated Certificate Management Division, Aircraft Certification Service. [FR Doc. 2025-24173 Filed 12-31-25; 8:45 am]BILLING CODE 4910-13-P