Airworthiness Directive · Amendment 39-22374 · Turbine engine compressor section
CFM International, S.A. Turbofan Engines
This AD applies to CFM International, S.A. (CFM) model turbofan engines identified in Table 1 to paragraph (c) of this AD with an installed high-pressure turbine (HPT) inner stationary seal, part number (P/N) 1808M56G01, that has a serial number (S/N) listed in Table 1 of CFM Service Bulletin (SB) CFM56-5B S/B 72-0952, Revision 02, dated August 10, 2022 (CFM SB CFM56-5B S/B 72-0952); Table 1 of CFM SB CFM56-5C S/B 72-0796, Revision 02, dated August 10, 2022 (CFM SB CFM56-5C S/B 72-0796); or Table 1 of CFM SB CFM56-7B S/B 72-1054, Revision 02, dated August 10, 2022 (CFM SB CFM56-7B S/B 72-1054). This AD does not apply to affected CFM CFM56-5B, CFM56-5C, and CFM56-7B model turbofan engines with the affected HPT inner stationary seal installed if the seal has been repaired as specified in CFM56-5B Engine Shop Manual (ESM), 72-41-03, REPAIR 003; CFM56-5C ESM, 72-41-03, REPAIR 003; or CFM56-7B ESM, 72-41-03, REPAIR 003, after December 31, 2012.
| Make | Model |
|---|---|
| CFM | CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/3, CFM56-5B1/P, CFM56-5B2, CFM56-5B2/2P, CFM56-5B2/3, CFM56-5B2/P, CFM56-5B3/2P, CFM56-5B3/2P1, CFM56-5B3/3, CFM56-5B3/3B1, CFM56-5B3/P, CFM56-5B3/P1, CFM56-5B4, CFM56-5B4/2P, CFM56-5B4/2P1, CFM56-5B4/3, CFM56-5B4/3B1, CFM56-5B4/P, CFM56-5B4/P1, CFM56-5B5, CFM56-5B5/3, CFM56-5B5/P, CFM56-5B6, CFM56-5B6/2P, CFM56-5B6/3, CFM56-5B6/P, CFM56-5B7, CFM56-5B7/3, CFM56-5B7/P, CFM56-5B8/3, CFM56-5B8/P, CFM56-5B9/2P, CFM56-5B9/3, CFM56-5B9/P. |
| CFM | CFM56-5C2, CFM56-5C2/4, CFM56-5C2/F, CFM56-5C2/F4, CFM56-5C2/G, CFM56-5C2/G4, CFM56-5C2/P, CFM56-5C3/F, CFM56-5C3/F4, CFM56-5C3/G, CFM56-5C3/G4, CFM56-5C3/P, CFM56-5C4, CFM56-5C4/1, CFM56-5C4/1P, CFM56-5C4/P. |
| CFM | CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3, CFM56-7B20E, CFM56-7B22, CFM56-7B22/2, CFM56-7B22/3, CFM56-7B22/3B1, CFM56-7B22/B1, CFM56-7B22E, CFM56-7B22E/B1, CFM56-7B24, CFM56-7B24/2, CFM56-7B24/3, CFM56-7B24/3B1, CFM56-7B24/B1, CFM56-7B24E, CFM56-7B24E/B1, CFM56-7B26, CFM56-7B26/2, CFM56-7B26/3, CFM56-7B26/3B1, CFM56-7B26/3B2, CFM56-7B26/3B2F, CFM56-7B26/3F, CFM56-7B26/B1, CFM56-7B26/B2, CFM56-7B26E, CFM56-7B26E/B1, CFM56-7B26E/B2, CFM56-7B26E/B2F, CFM56-7B26E/F, CFM56-7B27, CFM56-7B27/2, CFM56-7B27/3, CFM56-7B27/3B1, CFM56-7B27/3B1F, CFM56-7B27/3B3, CFM56-7B27/3F, CFM56-7B27/B1, CFM56-B27/B3, CFM56-7B27A, CFM56-7B27A/3, CFM56-7B27AE, CFM56-7B27E, CFM56-7B27E/B1, CFM56-7B27E/B1F, CFM56-7B27E/B3, CFM56-7B27E/F. |
The FAA is superseding Airworthiness Directive (AD) 2021-10-09 for certain CFM International, S.A. (CFM) CFM56-5B and CFM56-7B model turbofan engines with a certain high-pressure turbine (HPT) inner stationary seal installed. AD 2021-10-09 required removal, inspection, and replacement of the affected HPT inner stationary seal and, depending on the findings, replacement of the rotating air HPT front seal, HPT rotor blades, and No. 3 ball bearing. This AD was prompted by cracks found in the rotating air HPT front seal. After the FAA issued AD 2021-10-09, the manufacturer notified the FAA that the service information incorrectly lists the year of certain honeycomb repairs and that affected HPT inner stationary seals could potentially be installed on CFM CFM56-5C model turbofan engines. This AD requires removal, inspection, and replacement of the affected HPT inner stationary seal and, depending on the findings, replacement of the rotating air HPT front seal, HPT rotor blades, and No. 3 ball bearing. This AD also revises the applicability to add CFM CFM56-5C model turbofan engines. The FAA is issuing this AD to address the unsafe condition on these products.
(1) At the next engine shop visit after the effective date of this AD, remove the affected HPT inner stationary seal and replace with an HPT inner stationary seal that is eligible for installation.
(2) After removing the affected HPT inner stationary seal required by paragraph (g)(1) of this AD, inspect the removed HPT inner stationary seal for honeycomb separation in accordance with the Accomplishment Instructions, paragraph 3.C.(1), of CFM SB CFM56-5B S/B 72-0952; CFM SB CFM56-5C S/B 72-0796; or CFM SB CFM56-7B S/B 72-1054, as applicable by engine model.
(3) If honeycomb separation is found during the inspection required by paragraph (g)(2) of this AD, before further flight:
(i) Remove the rotating air HPT front seal from service and replace with a rotating air HPT front seal that is eligible for installation.
(ii) Remove the HPT rotor blades and replace with HPT rotor blades eligible for installation.
(iii) Remove the No. 3 ball bearing from service and replace with a No. 3 ball bearing eligible for installation.
(1) For the purpose of this AD, an “engine shop visit” is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine case flanges, except for the following situations, which do not constitute an engine shop visit.
(i) Separation of engine flanges solely for the purpose of transportation of the engine without subsequent maintenance.
(ii) Separation of engine flanges solely for the purpose of replacing the fan or propulsor without subsequent maintenance.
(2) For the purpose of this AD, an “HPT inner stationary seal that is eligible for installation” is an HPT inner stationary seal:
(i) That is not listed in Table 1 of CFM SB CFM56-5B S/B 72-0952; Table 1 of CFM SB CFM56-5C S/B 72-0796; or Table 1 CFM SB CFM56-7B S/B 72-1054; or
(ii) With a P/N 1808M56G01 and an S/N listed in Table 1 of CFM SB CFM56-5B S/B 72-0952; Table 1 of CFM SB CFM56-5C S/B 72-0796; or Table 1 of CFM SB CFM56-7B S/B 72-1054, that has been repaired as specified in CFM56-5B ESM, 72-41-03, REPAIR 003; CFM56-5C ESM, 72-41-03, REPAIR 003; or CFM56-7B ESM, 72-41-03, REPAIR 003, as applicable by engine model, after December 31, 2012.
(3) For the purpose of this AD, a “rotating air HPT front seal that is eligible for installation” is any rotating air HPT front seal that was not removed from service as a result of the inspection of the HPT inner stationary seal required by paragraph (g)(2) of this AD in which there was a finding of honeycomb separation.
(4) For the purpose of this AD, “HPT rotor blades eligible for installation” are new HPT rotor blades with zero flight hours since new or HPT rotor blades that have been inspected and returned to a serviceable condition using FAA-approved maintenance procedures.
(5) For the purpose of this AD, a “No. 3 ball bearing eligible for installation” is any No. 3 ball bearing that was not removed from service as a result of the inspection of the HPT inner stationary seal required by paragraph (g)(2) of this AD in which there was a finding of honeycomb separation.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
