COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Beechcraft 90 and 65-90 (King Air) Series Aeroplanes AD/BEECH 90/57 Amdt 4 Fuselage Fatigue Life Limitations 4/85 Applicability: All model F90 series. Requirement: 1. Retire the cabin door upper locking pins P/N 50-430177-3 and lower locking pins P/N 50-430018-9 from service. 2. Retire the pressure cabin from service. Compliance: 1. For Para. 1 - Upon or prior to the locking pins achieving 4500 pressurised flight cycles. 2. For Para. 2 - Before exceeding 8200 pressurised flights. Note: These lives may be revised following the completion of further tests and analysis currently being carried out by the manufacturer. Background: This amendment deletes the retirement life requirements for cabin and cockpit side windows. All model F90 aircraft now have the stretched acrylic failsafe windows installed, AD/Beech 90/70 refers.