COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Douglas DC3 Series Aeroplanes AD/DC3/20 Elevator Hinge Bracket - Inspection NK Applicability: All models. Requirement: 1. Inspect the elevator hinge arms, ribs and rear beams for cracks and stress raisers in the form of machining marks, badly formed rivets, rivet snap damage and nicks. 2. Replace cracked components. 3. If stress raisers are found take the following action: (a) For slight nicks, badly formed rivets, bruised metal around rivets - polish out or replace rivets as applicable. (b) For deep nicks, sharp edged snap damage - replace components. OR ANO 105.1.16.1.6.6.