COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 77 (Skipper) Series Aeroplanes AD/BEECH 77/11 Wing - Inspection, Bolt Replacement and Fatigue Life Limitation 10/82 Applicability: All models. Requirement: 1. Carry out the wing structure inspection and bolt replacement as detailed in Section 57-10-00 of the Beechcraft Skipper 77 Maintenance Manual. 2. Retire the wing and carry through structure from service as detailed in Section 4-00-00 of the Beechcraft Skipper 77 Maintenance Manual. Compliance: For Para. 1 - Upon or before achieving 7000 hours' time in service. For Para. 2 - Upon or before achieving 12000 hours' time in service. Background: The wing safe fatigue life of 12000 hours has been determined by the manufacturer by full scale fatigue test, and is dependent upon replacement of certain bolts, and successful inspection results, at 7000 hours.