COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Short SD3-60 Series Aeroplanes AD/SD3-60/33 Rudder Torque Tube Fitting 8/91 Applicability: Model SD360. Requirement: Action in accordance with Mandatory Shorts Service Bulletin SD360-55-17. Compliance: As specified in the Requirement Document with a revised effective date of 8 August 1991 for Australian registered aircraft. Background: Instances have been reported where the rudder torque tube fitting at rib 1 has been subject to exfoliation corrosion. The effective date required by the UK CAA is extended by three months.