COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 146 Series Aeroplanes AD/BAe 146/45 Airbrake Feedback Spring 5/93 Applicability: All BAe 146 series aircraft fitted with Servo-Valve assemblies P/N 3799H1 (Fairy Hydraulics) incorporating Servo-Valve P/N 72189 (Abex) in the S/N range as specified in the Requirement Document. Requirement: Action in accordance with BAe 146 mandatory Service Bulletin 27-133. Note: UK CAA AD 018-01-92 and DGAC 92-096-IMP(B) refer. Compliance: By 30 June 1993. Background: Advice has been received that due to faulty manufacture the Servo-Valve feedback spring may be fractured.