Airworthiness Directives; Turbomeca S.A. Turboshaft Engines

We are adopting a new airworthiness directive (AD) for certain Turbomeca S.A. Astazou XIV B and H turboshaft engines. This AD requires a one-time inspection of the front surface of the 3rd stage turbine for a groove. This AD was prompted by a report of a crack on the 3rd stage turbine wheel. We are issuing this AD to prevent cracks in the 3rd stage turbine wheel, failure of the engine, in-flight shutdown, and loss of control of the helicopter.