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 CAR 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. Pilatus Porter PC-6 Series Aeroplanes AD/PC-6/48 Horizontal Stabiliser Trim Setting 8/2002 DM Applicability: Model PC-6 aircraft, all Manufacturers Serial Numbers up to and including MSN 939. Requirement: Placard Installation: 1. Install placard Pilatus part number 110.71.06.611 on the heating tube above the instrument panel on the left side of the Stand-By Compass in clear view of the pilot; or, b. Fabricate placard in conspicuous colour with the following words, using letters at least ½- inch in height, and install this placard on the heating tube above the instrument panel on the left side of the Stand-By Compass in clear view of the pilot: "WARNING: SET CORRECT TRIM BEFORE TAKE-OFF" Flight Manual Revision: 1. Insert Pilatus PC-6 Aircraft Flight Manual Temporary Revision TR-TRIM 1, dated 26 August 1999, into Section 2 Operating Procedures of the Aircraft Flight Manual, and, 2. Insert Pilatus PC-6 Aircraft Flight Manual Temporary Revision TR-TRIM 3, dated 14 June 2002 into the Aircraft Flight Manual. Terminating action Installation of the trim warning system mandated by (Pilatus PC-6 Service Bulletin No. 180 Revision 1) constitutes terminating action for the Placard Installation, and Flight Manual Revision paragraph b. of this Directive. Note: Switzerland FOCA AD HB 2002-314 refers. Compliance: Before further flight after 3 July 2002, unless already accomplished. This Airworthiness Directive becomes effective on 3 July 2002. Pilatus Porter PC-6 Series Aeroplanes AD/PC-6/48 (continued) Background: The FOCA received reports of instances of PC-6 aircraft taking off with the horizontal stabiliser incorrectly trimmed. This situation could lead to control difficulties as soon as the aircraft becomes airborne. Despite the aircraft being in compliance with the applicable airworthiness requirements, a review of recent incidents has revealed the potential for improper operation. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 27 June 2002 The above AD is notified in the Commonwealth of Australia Gazette on 3 July 2002.