AD 2025-18-08 ACTIVE

The FAA is superseding Airworthiness Directive (AD) 2024-06-02 for all GE Aviation Czech s.r.o. (GEAC) Model M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F engines. AD 2024-06-02 required a one-time detailed visual inspection (DVI) of the compressor case pad welds for any crack, and replacement of the compressor case if necessary. Since the FAA issued AD 2024-06-02, the manufacturer determined that the compliance time for the DVI can be extended, and repetitive inspections of the centrifugal compressor case must be accomplished. This AD requires performing repetitive DVIs of the compressor case pad welds for any crack, replacing the compressor case if necessary, and sending certain inspection results to the manufacturer. The FAA is issuing this AD to address the unsafe condition on these products.

Final rule.

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: a. Removing Airworthiness Directive 2024-06-02, Amendment 39-22707 (89 FR 21196, March 27, 2024); and b. Adding the following new airworthiness directive: 2025-18-08 GE Aviation Czech s.r.o. (Type Certificate Previously Held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.): Amendment 39-23135; Docket No. FAA-2025-0627; Project Identifier MCAI-2024-00608-E. (a) Effective Date This airworthiness directive (AD) is effective October 21, 2025. (b) Affected ADs This AD replaces AD 2024-06-02, Amendment 39-22707 (89 FR 21196, March 27, 2024) (AD 2024-06-02). (c) Applicability This AD applies to GE Aviation Czech s.r.o. (GEAC) (type certificate previously held by WALTER Engines a.s. Walter a.s., and MOTORLET a.s.) Model M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F engines. (d) Subject Joint Aircraft System Component (JASC) Codes 7120, Engine Mount Section; 7230, Turbine Engine Compressor Section. (e) Unsafe Condition This AD was prompted by a report of a crack on the centrifugal compressor case mount pad weld area caused by a non-conforming weld (lack of welding penetration). The FAA is issuing this AD to prevent failure of the centrifugal compressor case. The unsafe condition, if not addressed, could result in crack propagation, possibly resulting in engine separation and reduced control of the airplane. (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, perform all required actions within the compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2024-0194, dated October 15, 2024 (EASA AD 2024-0194). (h) Exceptions to EASA AD 2024-0194 (1) Where EASA AD 2024-0194 requires compliance from its effective date, this AD requires using the effective date of this AD. (2) Where EASA AD 2024-0194 defines serviceable part as "Centrifugal compressor case, eligible for installation in accordance with GEAC instructions, which is not an affected part", this AD requires replacing that text with "centrifugal compressor case, eligible for installation, which is not an affected part". (3) Where EASA AD 2024-0194 specifies "Replacing the affected part of an engine with a centrifugal compressor case, eligible for installation in accordance with GEAC instructions, which is not an affected part", this AD requires replacing that text with "Replacing the affected part of an engine with a centrifugal compressor case, eligible for installation, which is not an affected part". (4) Where EASA AD 2024-0194 specifies to contact the manufacturer for approved instructions if any crack is detected on an affected part, this AD requires replacement of the compressor case. (5) This AD does not adopt the "Remarks" paragraph of EASA AD 2024-0194. (i) Alternative Methods of Compliance (AMOCs) The Manager, AIR-730 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 AIR-730 International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. (j) Additional Information For more information about this AD, contact Robert Charbonneau, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (781) 238-7132; email: robert.d.charbonneau@faa.gov . (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 2024-0194, dated October 15, 2024. (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: ADs@easa.europa.eu; website: easa.europa.eu. You may find this material on the EASA website at ad.easa.europa.eu. (4) You may view this material at FAA, 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 September 3, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2025-17852 Filed 9-15-25; 8:45 am]BILLING CODE 4910-13-P

Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2024-06-02, Amendment 39-22707 (89 FR 21196, March 27, 2024) (AD 2024-06-02). AD 2024-06-02 applied to all GEAC Model M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F engines. AD 2024-06-02 required a one-time DVI of the compressor case pad welds for any crack and replacement of the compressor case if necessary. The FAA issued AD 2024-06-02 to prevent failure of the centrifugal compressor case. The NPRM was published in the Federal Register on April 23, 2025 (90 FR 17022). The NPRM was prompted by EASA AD 2024-0194, dated October 15, 2024 (EASA AD 2024-0194) (also referred to as the MCAI) issued by EASA, which is Technical Agent for the Member States of the European Union. The MCAI states that since that AD was issued, it has been confirmed that the compliance time for the DVI can be extended, and that repetitive DVIs of the affected part must be accomplished. In the NPRM, the FAA proposed to require performing repetitive DVIs of the compressor case pad welds for any crack, replacing the compressor case if necessary, and sending certain inspection results to the manufacturer. You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2025-0627. Discussion of Final Airworthiness Directive Comments The FAA received no comments on the NPRM or on the determination of the costs. Conclusion 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 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, to include allowing the use of a part eligible for installation, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator. Material Incorporated by Reference Under 1 CFR Part 51 The FAA reviewed EASA AD 2024-0194, which specifies procedures for performing repetitive DVIs of the compressor case pad welds for any crack, replacement of the compressor case if necessary, and sending certain inspection results to the manufacturer. 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. Differences Between This AD and the MCAI GEAC Model M601D, M601D-1, M601D-2, M601D-11NZ, M601E, M601E-21, M601FS, and M601Z engines do not have an FAA type certificate, therefore this AD does not include those engines in the applicability. Costs of Compliance The FAA estimates that this AD affects 45 engines installed on airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: Estimated Costs Action Labor cost Parts cost Cost per product Cost on U.S. operators Inspect centrifugal compressor case 1 work-hour × $85 per hour = $85 $0 $85 $3,825 Report inspection results 1 work-hour × $85 per hour = $85 0 85 3,825 The FAA estimates the following costs to do any necessary replacements that would be required based on the results of the inspection. The agency has no way of determining the number of engines that might need this replacement: On-Condition Costs Action Labor cost Parts cost Cost per product Replace centrifugal compressor case 10 work-hours × $85 per hour = $850 $5,000 $5,850 The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected operators. Paperwork Reduction Act A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a currently valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. All responses to this collection of information are mandatory. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to: Information Collection Clearance Officer, Federal Aviation Administration, 10101 Hillwood Parkway, Fort Worth, TX 76177-1524. 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 has determined that 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. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 [Amended] 2. The FAA amends § 39.13 by: a. Removing Airworthiness Directive 2024-06-02, Amendment 39-22707 (89 FR 21196, March 27, 2024); and b. Adding the following new airworthiness directive: 2025-18-08 GE Aviation Czech s.r.o. (Type Certificate Previously Held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.): Amendment 39-23135; Docket No. FAA-2025-0627; Project Identifier MCAI-2024-00608-E. (a) Effective Date This airworthiness directive (AD) is effective October 21, 2025. (b) Affected ADs This AD replaces AD 2024-06-02, Amendment 39-22707 (89 FR 21196, March 27, 2024) (AD 2024-06-02). (c) Applicability This AD applies to GE Aviation Czech s.r.o. (GEAC) (type certificate previously held by WALTER Engines a.s. Walter a.s., and MOTORLET a.s.) Model M601D-11, M601E-11, M601E-11A, M601E-11AS, M601E-11S, and M601F engines. (d) Subject Joint Aircraft System Component (JASC) Codes 7120, Engine Mount Section; 7230, Turbine Engine Compressor Section. (e) Unsafe Condition This AD was prompted by a report of a crack on the centrifugal compressor case mount pad weld area caused by a non-conforming weld (lack of welding penetration). The FAA is issuing this AD to prevent failure of the centrifugal compressor case. The unsafe condition, if not addressed, could result in crack propagation, possibly resulting in engine separation and reduced control of the airplane. (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, perform all required actions within the compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2024-0194, dated October 15, 2024 (EASA AD 2024-0194). (h) Exceptions to EASA AD 2024-0194 (1) Where EASA AD 2024-0194 requires compliance from its effective date, this AD requires using the effective date of this AD. (2) Where EASA AD 2024-0194 defines serviceable part as "Centrifugal compressor case, eligible for installation in accordance with GEAC instructions, which is not an affected part", this AD requires replacing that text with "centrifugal compressor case, eligible for installation, which is not an affected part". (3) Where EASA AD 2024-0194 specifies "Replacing the affected part of an engine with a centrifugal compressor case, eligible for installation in accordance with GEAC instructions, which is not an affected part", this AD requires replacing that text with "Replacing the affected part of an engine with a centrifugal compressor case, eligible for installation, which is not an affected part". (4) Where EASA AD 2024-0194 specifies to contact the manufacturer for approved instructions if any crack is detected on an affected part, this AD requires replacement of the compressor case. (5) This AD does not adopt the "Remarks" paragraph of EASA AD 2024-0194. (i) Alternative Methods of Compliance (AMOCs) The Manager, AIR-730 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 AIR-730 International Validation Branch, send it to the attention of the person identified in paragraph (j) of this AD and email to: AMOC@faa.gov. (j) Additional Information For more information about this AD, contact Robert Charbonneau, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (781) 238-7132; email: robert.d.charbonneau@faa.gov . (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 2024-0194, dated October 15, 2024. (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: ADs@easa.europa.eu; website: easa.europa.eu. You may find this material on the EASA website at ad.easa.europa.eu. (4) You may view this material at FAA, 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 September 3, 2025. Steven W. Thompson, Acting Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2025-0627; 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, 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. It is also available at regulations.gov under Docket No. FAA-2025-0627.

Robert Charbonneau, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (781) 238-7132; email: robert.d.charbonneau@faa.gov .