COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES De Havilland Piston Engines AD/DHE/20 Amdt 1 Propeller Shaft - Inspection and Modification 3/68 Applicability: All GQ 70 series which have been repaired in accordance with one or more of the following modifications and repair schemes. Mod. 1399 (R155), Mod. 1609 (R259), Mod. 2289 (R155 and R259, with introduction of 70 Mk. 2). Mod. 2931 (R563 and R564) Repair scheme R155 and R259 (70 Mk. 3). Document: Inspection - Bristol Siddeley TNS GQ70 No. 105 Modification - Mod. No. 2925. Compliance: Inspection - within 100 hours time in service after 21 March 1968 and thereafter at intervals not exceeding 400 hours time in service until Mod. 2925 is incorporated. Modification - Before installation is an aircraft following next overhaul completed after 21 March 1968.