COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES SAAB SF340 Series Aeroplanes AD/SF340/53 Anti-Skid Drive Coupling 5/96 DM Applicability: All SAAB SF340A S/N 004 through 159 and SF340B S/N 160 through 378 aircraft. Requirement: Unless previously carried out, action in accordance with SAAB Service Bulletin 340- 32-107 dated 18 January 1996. Note: Swedish AD No 1-085 R1 refers. Compliance: Prior to 30 April 1996. Background: The manufacturer has advised that numerous occurrences of unexpected brake pressure reductions have been reported. In one incident an aircraft ran into an airport building.