Superseded. This AD was superseded by AD 2023-05-05. Verify which one applies to your serial and effectivity before any maintenance action.
AD 2021-10-09
Effective 06/24/2021 · Published 05/20/2021
Airworthiness Directives; CFM International, S.A. Turbofan Engines
Summary
The FAA is adopting a new airworthiness directive (AD) for all CFM International, S.A. (CFM) CFM56-5B and CFM56-7B model turbofan engines with a certain high-pressure turbine (HPT) inner stationary seal installed. This AD was prompted by cracks found in the rotating air HPT front seal. This AD requires removal, inspection, and replacement of the affected HPT inner stationary seal and, depending on the findings, repl…