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/TB20/33 Upper Attachment of Front Seat Belts 11/96 DM Applicability: S/Nos. 1 to 1701, 1707 to 1750, 1758 to 1763, 1767 and 1769. Requirement: Action in accordance with Socata SB 10-103-25. Note: DGAC AD 96-143(A) refers. Compliance: Within 50 hours time in service, or 30 days, after 14 August 1996 whichever occurs first. Background: This Directive is issued to ensure the integrity of the upper attachment of the front seat belts.