COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 60 (Duke) Series Aeroplanes AD/BEECH 60/36 Fuselage Fatigue Life Limitation 3/81 Applicability: All model 60, A60 and B60 Series. Requirement: Retire the pressure cabin from service. Compliance: Before exceeding 12,800 pressurised flights. Background: Analysis and fatigue tests by the manufacturer have established the above pressure cabin life for these aircraft.