COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Fokker F27 Series Aeroplanes AD/F27/143 Port Elevator Torque Tube 4/97 Applicability: F27 Mk 100 to Mk 700 all serial numbers. Requirement: Inspect in accordance with Fokker SB F27/55-66. Note: RLD AD 1995-007 refers. Compliance: Prior to the accumulation of 45 000 flight cycles or before 31 July 1997, whichever occurs last. This Airworthiness Directive becomes effective on 27 March 1997. Background: This Directive is raised following the report of cracking found on the torque tube support of the port elevator.