COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES DHC-2 (Beaver) Series Aeroplanes AD/DHC-2/28 Wing Strut Lower Steel End-Fitting 12/93 Applicability: Model DHC-2 aircraft with steel end-fittings on C2W1115-1/-2 wing struts. Requirement: Visually inspect the wing strut in accordance with de Havilland Alert Service Bulletin No. A2/48. If damage is detected, repair or replace the strut in accordance with the above mentioned Service Bulletin. Note: Transport Canada AD CF-93-21 refers. Compliance: Within 50 hours time in service after 11 November 1993, and thereafter at intervals not to exceed 12 calendar months. Background: Service difficulty reports received by Transport Canada indicated the occurrence of skin corrosion and fastener damage at the wing strut lower steel end-fittings.