Airworthiness Directives; Hamilton Standard 54H60 Series Propellers

This amendment adopts a new airworthiness directive (AD) that is applicable to Hamilton Standard 54H60 series propellers. This action requires affected propeller blades to be removed from service and shipped to designated repair facilities for inspection for insufficient cold rolling of the beveled radius of the blade flange. Affected blades are identified by serial number. This amendment is prompted by reports of propeller blades that cracked due to incomplete cold rolling in the beveled radius area of the blade flange. The actions specified in this AD are intended to prevent propeller blade cracks due to incomplete cold rolling during manufacture, which can result in propeller blade separation and damage to the aircraft.