COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES 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-6/50 Inboard Fuel Tanks Rib Structure 3/2003 Applicability: Model PC-6 Series aircraft, with serial numbers up to and including MSN 939. Requirement: Action in accordance with Pilatus Aircraft Mandatory Service Bulletin No. 57-002 Note: Switzerland FOCA AD HB 2003-092 refers. Compliance: For Part A of the Requirement document: At the next scheduled maintenance inspection after 20 March 2003 or before 30 June 2003, whichever occurs first. For Part B of the Requirement document: If Service Bulletin No. 118 is not incorporated, accomplish before 30 September 2003. This Airworthiness Directive becomes effective on 20 March 2003. Background: Crack damage has occurred in the ribs in the inboard integral fuel tanks in the left and right wings of PC-6 aircraft. David Alan Villiers Delegate of the Civil Aviation Safety Authority 6 February 2003 The above AD is notified in the Commonwealth of Australia Gazette on 26 February 2003. Page 1 of 1