COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Twin Commander (Gulfstream/Rockwell/ Aerocommander 500, 600 and 700) Series Aeroplanes AD/AC/36 Amdt 2 Wing Front Spar Lower Cap - Inspection 11/70 Applicability: All models 560E, 680 and 680E which do not embody an external or internal spar reinforcement extending to W.S. 127 approved by the Secretary. Document: Aero Commander SB No. 92. Compliance: At or before 3000 hours' time in service unless already accomplished.