Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to Allison Engine Company, Inc. AE 3007A and AE 3007C series turbofan engines. This proposal would require removing certain turbine wheels from service before exceeding new, reduced cyclic life limits. This proposal is prompted by a refined life analysis that was performed by the manufacturer. The actions specified by the proposed AD are intended to prevent an uncontained turbine wheel failure, which could result in damage to the airplane.