COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES DHC-6 (Twin Otter) Series Aeroplanes AD/DHC-6/15 Amdt 1 Wing Strut Jo-Bolt - Inspection 1/83 Applicability: All models with S/Nos. 1 to 170. Document: De Havilland Aircraft of Canada SB No. 6/166, Rev. B. Compliance: As detailed in the requirement document. Background: AD revised to reflect requirement document revision status.