COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace BAe 3100 (Jetstream) Series Aeroplanes AD/JETSTREAM/17 Amdt 3 Elevator Trim Servo Cable P/N 137187E472 11/97 Applicability: All Jetstream Series 3100 aircraft, with Sperry SPZ-200B autopilot installed. Jetstream Series 3100 aircraft, with Sperry SPZ-500 autopilot installed, excluding aircraft that have autopilot installed under Customer Requirement Kit JK2864 (Service Bulletin 34-JK2864). Requirement: Action in accordance with Jetstream Alert Service Bulletin 22-A-JA 861023 Revision 3. This Alert Service Bulletin has been classified mandatory by the UK CAA. Note: Jetstream SB 27-JK 12006 introduced a new cable with a life limitation of 4,000 hours time in service. Compliance: As specified in Part J of the requirement document. Background: The manufacturer reported a case of cable failure that left the trim tab in an irreversible position whilst giving a cockpit indication that all was normal. Amendment 1 reduced the cable life limit from 2,000 hours to 1,000 hours. Amendment 2 introduced an improved 7x19 elevator trim cable with an increased life limit. Amendment 3 is issued in response to a revision of the requirement document which clarifies both the applicability and compliance requirements. Amendment 2 of this airworthiness directive became effective on 12 October 1995. Amendment 1 of this airworthiness directive became effective on 17 January 1989. The original issue of this airworthiness directive became effective on 18 December 1986.