COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Gulfstream (Grumman American/ American Aviation) AA-5 Series Aeroplanes AD/AA-5/19 Carburettor Heat Valve - Inspection NK and Modification Applicability: All models AA-5 with S/Nos. AA5-0641 to AA5-0834, and all models AA-5A with S/Nos. AA5A-0001 to AA5A-0321. Document: Grumman American SB No. 159. Compliance: 1. For Part 1 of the SB Instructions - before further flight. 2. For Parts II and III of the SB Instructions - in accordance with the Service Bulletin.