COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Percival Vega Gull Series Aeroplanes AD/GULL/1 Amdt 1 Wing Rib to Aileron Spar Joint - Inspection 11/67 Applicability: All models not modified in accordance with Percival Mod. No. 130. Requirement: 1. Inspect the points of attachment of the outer wing ribs to the aileron false spar. 2. If the area shows signs of faulty gluing or failure of joints, strengthen the rib to spar attachment in accordance with Percival Modification No. 130, or 3. ANO 105.1.26.0.2.1. Compliance: At intervals not exceeding 12 months or 100 hours time in service whichever occurs first.