AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section. Fokker F100 (F28 Mk 100) Series Aeroplanes AD/F100/61 Aileron Tab Drive Rod Assembly 4/2004 Applicability: Fokker Aircraft B.V. F.28 Mk.0070 and Mk.0100 aircraft, all serial numbers. Requirement: 1. Perform a one-time inspection of the Aileron Tab Drive Rod Assembly on each actuator in accordance with Part 2 Accomplishment Instructions of Fokker Service Bulletin (S/B) F100-27-083 dated 20 October 2003. 2. If the clearance between the hydraulic line and the Aileron Tab Drive Rod is 4 mm or more, no further action is required. 3. When chafing damage is found on the Aileron Tab Rod Part Number (P/N) D78896-001, rework and/or replace any affected parts in accordance with steps B.(1)(a) and B.(1)(b) of Part 2 Accomplishment Instruction of the reference document. 4. If the clearance between the hydraulic line and the Aileron Tab Drive Rod is less than 4 mm, take corrective action in accordance with B.(2)(b)3 though B.(2)(b)9 of the reference document. Note: Civil Aviation Authority Netherlands BLA nr AD 2003-141 refers. Compliance: For Requirement 1: Unless previously accomplished, within 2 years or 4,000 flight hours after the effective date of this Directive. For Requirements 3 and 4: Before further flight following completion of Requirement 1 of this Directive. This Airworthiness Directive becomes effective on 15 April 2004. Fokker F100 (F28 Mk 100) Series Aeroplanes AD/F100/61 (continued) Background: Rotation of the Aileron actuator can occur if the polyamide washer, which is fitted between the actuator and the airframe, is severely worn. The rotation of the actuator can lead to chafing of the aileron tab drive rods and subsequent failure of the aileron tab in manual mode. This Directive requires a one-off inspection and rectification as required to prevent the unsafe condition occurring. An update of the aeroplane maintenance manual will introduce revised inspection intervals to prevent recurrences of such failures. James Coyne Delegate of the Civil Aviation Safety Authority 4 March 2004 The above AD is notified in the Commonwealth of Australia Gazette on 24 March 2004.