COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes 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. AD/CL-600/43 Cargo Compartment Smoke Detector 9/2001 Applicability: Model CL-600-2B19 "Regional Jet" aeroplanes, serial numbers 7003 through 7480 inclusive. Requirement: Replace the cargo compartment smoke detectors Part Number (P/N) 473052 with new smoke detectors P/N 473597-19 in accordance with Bombardier Service Bulletin 601R-26-016 dated 23 March 2001 or Revision A dated 15 June 2001. Note: Transport Canada AD CF-2001-21 refers. Compliance: Within 15 months after the effective date of this Directive. This Airworthiness Directive becomes effective on 6 September 2001. Background: Transport Canada has advised that the cargo compartment smoke detectors have proved to be susceptible to dirt, condensation and electromagnetic interference. This has resulted in a significant number of in-flight false "CARGO SMOKE" warning messages being posted on the Engine Indication and Crew Alerting System (EICAS). False smoke warnings undermine the effectiveness of the system to the flight crew. James Coyne Delegate of the Civil Aviation Safety Authority 23 July 2001 The above AD is notified in the Commonwealth of Australia Gazette on 15 August 2001.