COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Victa and A.E.S.L. Airtourer Series Aeroplanes AD/VAT/20 Centre Flap Spar - Inspection 6/64 Applicability: Victa Airtourer 100 and 115 not incorporating Victa Mod. B141 and which have exceeded 500 hours time in service. Requirement: Inspect the centre flap spar in the region of the actuating bracket P/N 16105/1 for cracking. If cracking is found repair in accordance with an approved scheme before further flight. Compliance: At intervals not exceeding 100 hours time in service, after 1 September 1971.