EASA AD 2021-0264R1
Engine — Critical Parts — Replacement
Summary
EASA Airworthiness Directive 2021-0264R1 is a regulatory update addressing critical parts replacement for GE Aviation Czech M601 series engines installed on various aircraft including the Aircraft Industries L-410 and L-420, Air Tractor AT series, Allied Ag Cat G-164, Thrush S-2R, and Viking Air DHC-3 Otter. The directive focuses on ensuring the replacement and proper identification of affected compressor cases and drums to prevent engine failures. It mandates compliance with specific life limits and logbook corrections to maintain engine airworthiness.
What Changed
This revision removes replacement requirements for Group 1 engines that have been incorporated into the Airworthiness Limitations Section (ALS) of the engine maintenance manual. It retains replacement and logbook correction requirements for Group 2 engines and affected compressor drums. The directive also clarifies installation conditions for compressor cases and updates compliance instructions according to the latest GE Aviation Czech Alert Service Bulletin revisions.
Why It Matters
This directive is critical for aviation professionals to prevent potential engine part failures that could lead to engine mount failure or release of high-energy debris, posing safety risks. Operators and maintenance organizations must ensure affected parts are replaced within specified life limits and that engine logbooks accurately reflect part identification. Compliance helps maintain regulatory conformity and ensures continued airworthiness of aircraft equipped with these engines.
What To Do
Operators must replace affected compressor cases on Group 2 engines and all affected compressor drums before exceeding their recalculated life limits or within 12 months after 6 December 2021, whichever occurs first. They must also review and correct engine logbooks within 6 months after 6 December 2021 to ensure accurate part number identification. Installation of certain compressor cases and drums is restricted unless conditions specified in the directive are met.
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