Airworthiness Directives; Hartzell Propeller Inc. ( )HC-( )(2,3)(X,V)( )-( ) Series and HA-A2V20-1B Series Propellers with Aluminum Blades

This amendment revises an existing airworthiness directive (AD), that is applicable to Hartzell Propeller Inc. ( )HC-( )(2,3)(X,V)( )-( ) series and HA-A2V20-1B series propellers with aluminum blades. That AD currently requires initial and repetitive dye penetrant and eddy current inspections of the blade and an optical comparator inspection of the blade retention area, and, if necessary, replacement with serviceable parts. In addition, that AD currently requires initial and repetitive visual and magnetic particle inspection of the blade clamp, dye penetrant inspection of the blade internal bearing bore, and, if necessary, replacement with serviceable parts. Also, for all HC-(1,4,5,8)(2,3)(X,V)( )-( ) steel hub propellers, that AD currently requires an additional initial and repetitive visual and magnetic particle inspection of the hub, and, if necessary, replacement with serviceable parts. This amendment revises that AD by permitting the replacement of affected propellers with Hartzell Propeller Inc. model "MV" series propellers as an optional terminating action for the initial and repetitive inspections of that AD. This amendment is prompted by type certification approval of the Hartzell "MV" series propellers that are direct replacements for the affected propellers, and service bulletin approval to allow modification of affected propellers to the "MV" type design configuration. The actions specified by this AD are intended to prevent blade separation due to cracked blades, hubs, or blade clamps, which can result in loss of control of the airplane.