Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Hartzell Propeller Inc. propellers. This proposed AD would require inspecting the propeller blades and other critical propeller parts for corrosion and mechanical damage. This proposed 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 proposing 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.