EASA AD US-2024-12-03
Engine - High-Pressure Turbine Stage 1 and Stage 2 Disks - Replacement
Summary
The Federal Aviation Administration's Airworthiness Directive 2024-12-03 addresses certain CFE Company Model CFE738-1-1B engines. It mandates the replacement of high-pressure turbine (HPT) stage 1 and stage 2 disks suspected to contain iron inclusions due to manufacturing defects. This directive aims to prevent potential structural failures and uncontained engine debris release.
What Changed
This new airworthiness directive introduces a mandatory replacement requirement for affected HPT stage 1 and stage 2 disks identified by specific part and serial numbers in CFE Service Bulletin CFE738-72-A8082. It establishes compliance timelines based on cycles since new or piece-part exposure. The directive incorporates the service bulletin by reference to guide the replacement process.
Why It Matters
This directive is critical for aviation professionals as it addresses a latent manufacturing defect that could lead to premature disk fracture and uncontained engine failures. Operators and maintenance organizations must ensure timely compliance to maintain engine integrity and flight safety. Compliance teams need to track affected parts and manage replacements to avoid regulatory penalties and operational disruptions.
What To Do
Operators of aircraft with CFE Model CFE738-1-1B engines must inspect installed HPT stage 1 and stage 2 disks against the affected part and serial numbers listed in the referenced service bulletin. Replacement of affected disks must occur at the next piece-part exposure or before reaching 2,450 cycles since new for stage 1 disks, and 2,930 cycles since new for stage 2 disks, whichever comes first. All replacements must use parts eligible for installation as defined in the directive.