COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 125 Series Aeroplanes AD/HS 125/153 Thrust Reverser Secondary Locks, Microswitches and Wiring 12/95 Applicability: BAe 125 Series 1000A, 1000B and Hawker 1000 aircraft Pre Mod 253352 and Post Mod 253352. Requirement: Incorporate thrust reverser secondary locks microswitches and wiring in accordance with Hawker Raytheon Corporate Jets Service Bulletin SB. 78-14-3691A, B & E dated 21 June 1995. Note: CAA (UK) AD 004-06-95 refers. Compliance: Prior to 1 March 1996. Background: The manufacturer has advised of the possibility of failure of a drive link or its attachments which may result in an inadvertent in-flight thrust reverser deployment. This Directive requires the installation of a secondary locking feature to the thrust reversers in order to meet the certification requirements.