Airworthiness Directives; Hartzell Propeller Inc. Propellers

The FAA is adopting a new airworthiness directive (AD) for certain Hartzell Propeller Inc. propellers. This AD requires inspecting the propeller blades and other critical propeller parts for corrosion and mechanical damage. This AD results from two events where a "Z- shank" blade failed and separated and the results of teardown inspections that detected corrosion in the blade bore. We are issuing this AD to detect corrosion and mechanical damage that can cause failure of a propeller, which could result in loss of control of the airplane.