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/TB20/31 Main Landing Gear 8/95 DM Applicability: TB20 and TB21 aircraft, on which the ring on the attachment bearing of the LH or RH main landing gear has been removed and replaced during maintenance. Requirement: Action in accordance with Socata TB Service Bulletin SB10.091.57. Note: DGAC AD 95-084(A) refers. Compliance: Within 50 hours time in service after 31 May 1995, or prior to 31 July 1995, whichever occurs first. Background: This Directive is issued to ensure that the rings, when replaced, have been correctly installed on the attachment bearing of the hinged strut.