Airworthiness Directives; Allison Engine Company AE 3007 Series Turbofan Engines

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Allison Engine Company AE 3007 series turbofan engines. This AD would require removal of certain cone shafts from service before exceeding new cyclic life limits and replacement with serviceable parts. This amendment is prompted by additional testing and low cycle fatigue (LCF) life analysis that substantiate lower cyclic lives than originally determined. The actions specified by this AD are intended to prevent LCF failure of cone shafts, which could result in an uncontained engine failure and damage to the aircraft.