COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Cessna 336 Series Aeroplanes AD/CESSNA 336/10 Wing Front Carry Thru Spar Inspection and Modification 5/74 Applicability: All models with S/Nos. 336-0001 to 336-0195 not modified in accordance with Service Kit SK 336-19A. Document: Cessna SL ME74-4. Compliance: For aircraft with more than 2975 hours total time in service as at 14 May 1974 - within 25 hours time in service after 14 May 1974, and thereafter at intervals not exceeding 100 hours time in service. For all other aircraft - before exceeding 3000 hours total time in service and thereafter at intervals not exceeding 100 hours time in service.