The Federal Aviation Administration (FAA) is proposing to supersede Airworthiness Directive
(AD) 2021-13-07 (dated June 14, 2021) which applies to several GE Aviation Czech s.r.o. M601 turboprop engines. The original AD was based on the European Union Aviation Safety Agency
(EASA) AD 2021-0125-E, and required recalculating the life of critical parts and replacing a certain compressor case.
Since the original AD was issued, the manufacturer published the airworthiness limitations section (ALS) of the existing engine maintenance manual, which includes the calculations for the life of critical parts addressed by the original AD. EASA revised AD 2021-0125-E and issued
AD 2021-0125R1 (dated January 30, 2023) to limit the applicability and remove the requirements that have been incorporated into the ALS.
The
FAA’s proposed superseding AD would continue to require replacement of a certain compressor case and include an additional part number as an option for replacement and would limit the applicability as specified in EASA 2021-0125R1. The FAA will be addressing the
actions specified in the ALS concurrently in a separate AD action.
