COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Douglas DC4 Series Aeroplanes AD/DC4/26 Feathering Pump Line - Replacement NK Applicability: All models. Requirement: Remove the duralumin pump assembly (P/N 5229000) running from the propeller feathering pump to the firewall and replace with 5/8 in. outside diameter x 18 SWG stainless steel or cadmium plated chrome molybdenum tubing; or ANOs Part 100, Appendix "A" Notice No. 22/6; or ANO 105.1.16.2.5.25.