COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes AIRWORTHINESS DIRECTIVE For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/DHC-8/73 and issues the following 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. AD/DHC-8/73 Amdt 1 Airstair Door 4/2001 Applicability: Model DHC-8 series 100, 200, and 300 aircraft, serial numbers 003 through 550. Requirement: Modify the airstair door in accordance with the requirements of Transport Canada AD CF-2000-19R1. Compliance: Before 19 October 2001, unless already accomplished. This amendment becomes effective on 19 April 2001. Background: Transport Canada received a significant number of reports which detail various problems of the airstair door failing to open following flight. Several modifications have been developed to address these problems and their incorporation will improve the reliability of the airstair door, and ensure that problems with the door do not impede aircraft egress during emergency conditions. Amendment 1 is issued in response to a new Transport Canada AD which addresses a change in affected aircraft serial numbers, indicates approval of later revisions of two service bulletins, and adds an alternate method of addressing the bending of the gas springs. As well, the compliance schedule has been extended. The original issue of this Airworthiness Directive became effective on 2 November 2000. David Alan Villiers. Delegate of the Civil Aviation Safety Authority 5 March 2001 The above AD is notified in the Commonwealth of Australia Gazette on 21 March 2001.