Airworthiness Directives; CFM International S.A. Turbofan Engines

FAA / Federal Register · 2019-20054

The FAA proposes to adopt 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 proposed AD was prompted by cracks found in the rotating air HPT front seal. This proposed AD would require removal, inspection, and replacement of the affected HPT inner stationary seal, and depending on the findings, removal and replacement of the rotating air HPT front seal. The FAA is proposing this AD to address the unsafe condition on these products.