Airworthiness Directives; GE Aviation Czech s.r.o. Turboprop Engines

We are adopting a new airworthiness directive (AD) for certain serial number GE Aviation Czech s.r.o. M601E-11, M601E-11A, and M601F turboprop engines. This AD requires inspection of the reduction gearbox and supporting cone. This AD was prompted by the determination that wear or cracking, and subsequent misalignment of the quill shaft of the engine and the power turbine (PT) shaft, may lead to rupture of the quill shaft, overspeed of the PT, and uncontained engine failure. We are issuing this AD to prevent misalignment and rupture of the quill shaft, which could lead to overspeed of the PT, uncontained engine failure, and damage to the airplane.