Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company) 501-D Series Turboprop Engines

This amendment adopts a new airworthiness directive (AD), that is applicable to Rolls-Royce Corporation (formerly Allison Engine Company) 501-D series turboprop engines. This amendment requires removal from service of certain turbine rotor components at reduced life limits. This amendment is prompted by the result of recalculated material properties by the manufacturer. The actions specified by this AD are intended to prevent uncontained turbine rotor failure resulting in in-flight engine shutdown and possible damage to the airplane.