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 125/157 Rudder Flow Separator Triggers and Strut Spring 12/97 Applicability: Model BAe 125 Series 800A and Series 800B, and Model Hawker 800 and Hawker 800XP series aircraft; on which Raytheon Modification 25FO17A&B has not been installed. Requirement: Modify the rudder in accordance with Raytheon Service Bulletin 55-36-25FO17A&B. Note: FAA AD 97-18-07 Amdt 39-10117 refers. Compliance: Unless already accomplished, within 100 hours time in service or within 6 months after 6 November 1997, whichever occurs first. This airworthiness directive becomes effective on 6 November 1997. Background: The FAA received a report indicating that, due to the existing design of the rudder, overbias or overbalance of the rudder occurs during single engine handling. The actions specified by this Directive are intended to prevent this occurrence, which could result in reduced controllability of the aircraft.