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/21 Fuel Tank Retention Buttons - Modification 11/64 Applicability: Victa Airtourer 100 and 115 with S/Nos. 1 to 75. Document: Victa SB No. 44. Compliance: Within 100 hours time in service after 20 November 1964.