AD 2021-11-07 Airworthiness Directives; General Electric Company Turbofan Engines

This AD applies to: (1) General Electric Company (GE) GEnx-1B64, GEnx-1B64/P1, GEnx-1B64/P2, GEnx-1B67, GEnx-1B67/P1, GEnx-1B67/P2, GEnx-1B70, GEnx-1B70/75/P1, GEnx-1B70/75/P2, GEnx-1B70/P1, GEnx-1B70/P2, GEnx-1B70C/P1, GEnx-1B70C/P2, GEnx-1B74/75/P1, GEnx-1B74/75/P2, GEnx-1B76/P2, GEnx-1B76A/P2 model turbofan engines with stages 6-10 compressor rotor spools in the high-pressure compressor (HPC) assembly with the following part numbers (P/N) installed: (i) P/N 2357M30G01, P/N 2357M30G02, P/N 2439M35G01, P/N 2439M35G02, or P/N 2445M40G02, all serial numbers (S/Ns); (ii) P/N 2610M90G01 with the S/Ns listed in paragraph 4., APPENDIX—A, Table 1 of the GE GEnx-1B Service Bulletin (SB) 72-0472 R02, dated November 5, 2020 (GEnx-1B SB 72-0472); and (iii) P/N 2628M56G01 with the S/Ns listed in paragraph 4., APPENDIX—A, Table 2 or Table 3 of GEnx-1B SB 72-0472. (2) GEnx-2B67, GEnx-2B67/P, GEnx-2B67B model turbofan engines with the following stages 6-10 compressor rotor spools P/Ns installed: (i) P/N 2357M30G02, P/N 2439M35G02, or P/N 2445M40G02, all S/Ns; (ii) P/N 2340M36G01 with S/Ns listed in paragraph 4., APPENDIX—A, Table 1 of GE GEnx-2B SB 72-0415 R02, dated November 5, 2020 (GEnx-2B SB 72-0415); and (iii) P/N 2628M56G01 with S/Ns listed in paragraph 4., APPENDIX—A, Table 2 or Table 3 of GEnx-2B SB 72-0415.

Comply with this AD within the compliance times specified, unless already done.

(1) For all affected GEnx-1B and GEnx-2B model turbofan engines, before exceeding the compliance time in Table 1 to paragraph (g)(1) of this AD, perform a borescope inspection (BSI) or eddy current inspection (ECI) of the stage 6, stage 7, and stage 8 webs, web transitions, and bore faces of the stages 6-10 compressor rotor spool in accordance with the Accomplishment Instructions, paragraph 3, of GEnx-1B SB 72-0472 (for GEnx-1B models) or the Accomplishment Instructions, paragraph 3, of GEnx-2B SB 72-0415 (for GEnx-2B models). Table 1 to Paragraph ( g )(1) Cycles Since New (CSN) accumulated on the stages 6-10 compressor rotor spool Compliance time Less than 6,400 CSN Next engine shop visit or before the stages 6-10 compressor rotor spool accumulates 6,500 CSN, whichever occurs first after the effective date of this AD. 6,400 CSN or greater Within 100 flight cycles after the effective date of this AD. (i) For GEnx-1B model turbofan engines, except those identified in paragraph 4, APPENDIX—A, Table 3 of SB 72-0472, if, before the effective date of this AD, the engines have undergone inspections of the aft web of stage 6, stage 7, and stage 8 of the stages 6-10 compressor rotor spool using both GE GEnx-1B SB 72-0448 R00, dated July 29, 2019, and GE GEnx-1B SB 72-0460 R00, dated October 30, 2019, regardless of the CSN accumulated on the stages 6-10 compressor rotor spool, perform the inspection required by paragraph (g)(1) of this AD no later than the next engine shop visit after the effective date of this AD. (ii) For GEnx-2B model turbofan engines, except those identified in paragraph 4., APPENDIX—A, Table 3 of SB 72-0415, if, before the effective date of this AD, the engines have undergone inspections of the aft web of stage 6, stage 7, and stage 8 of the stages 6-10 compressor rotor spool using both GE GEnx-2B SB 72-385 R02, dated July 29, 2019, and GE GEnx-2B SB 72-0398 R00, dated October 30, 2019, regardless of the CSN accumulated on the stages 6-10 compressor rotor spool, perform the inspection required by paragraph (g)(1) of this AD no later than the next engine shop visit after the effective date of this AD. (2) For all affected GEnx-1B and GEnx-2B model turbofan engines, during the inspections required by paragraph (g)(1) of this AD, if a rejectable indication is found, before further flight, remove the stages 6-10 compressor rotor spool from service and replace it with a part eligible for installation.

This AD was prompted by a finding during an inspection that two stages 6-10 compressor rotor spools were damaged at similar locations. In addition, the manufacturer reported that certain stages 6-10 compressor rotor spool webs did not undergo a required fluorescent penetrant inspection (FPI) during production. The FAA is issuing this AD to prevent failure of the compressor rotor spool. The unsafe condition, if not addressed, could result in uncontained release of debris, damage to the engine, and damage to the airplane.

None.