COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Aerospatiale (Socata) TB20 (Trinidad) Series Aeroplanes AD/TB20/24 Fuel Tank Outlet Filter 2/92 Applicability: Model TB20 and TB21 with serial number 1038 to 1308 inclusive. Aircraft S/N 1213, 1264 through 1267, 1284 through 1287, 1301 through 1304 and 1307 have previously been modified. Requirement: Action in accordance with the technical requirement of DGAC AD 91-246(A). Note: Socata TB airplanes SB Nr 61 refers. Compliance: During the next periodic inspection after the 25 January 1992 or by 30 June 1992, whichever occurs first. Background: This Directive has been raised to ensure sump volume and unusable fuel quantity are correct.