Airworthiness Directives; Hartzell Propeller Inc., Model HC-C2YR-4CF Propellers

This amendment adopts a new airworthiness directive (AD), that is applicable to Hartzell Propeller Inc. model HC-C2YR-4CF propellers. This amendment requires the reduction of the original hub and blades certified service (fatigue) life from unlimited hours to 2,000 hours. This amendment is prompted by a reevaluation by Hartzell Propeller Inc. of the original hub and blades service life certification calculations. The actions specified by this AD are intended to prevent fatigue failure of the original propeller hub and blades which may result in loss of airplane control.