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 5/26 Fuel Tanks 2/90 Applicability: Model AA 5, AA 5A and AA 5B. Requirement: Inspect the fuel tanks, fuel system, and the electric fuel pump filter for fuel tank sealant contamination in accordance with the instructions specified in Gulfstream Aerospace Corporation Service Bulletin No 176. Note: FAA AD 89-18-08 Amdt 39-6307 refers. Compliance: Prior to the issue of the next Maintenance Release after 30 April 1990. Background: Integral fuel tanks were sealed at manufacture with sealant which has since been determined to be unsuitable for use in a high- octane fuel environment. Fuel Tank Repair Service Kit No 140 also specified the use of this sealant, but was subsequently reissued containing the correct sealant as Kit No 140A. The requirement of this AD will ensure against possible fuel contamination and/or flow interruption to the engine.