COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Skyfox Aviation (Calair/Hedaro) CA21 and CA22A Series Aeroplanes AD/CA21/6 Life Limited Components 3/96 Applicability: All CA21 and CA22A aircraft. Requirement: The following components are to be retired from service at the times shown: Component Maximum Time in Service Wing Front and Rear Spars 4000 Hours Wing Lift Struts and Carry-Through Structure 4000 Hours Horizontal Stabiliser Spar 8000 Hours All Other Structure, Except Doors and Fairings 8000 Hours Compliance: As specified in the Requirement, with effect from 29 February 1996. Background: The fatigue life limits in this Directive are the best estimates, based on stress and fatigue analyses supplied by the manufacturer.