AD/DHC-8/93 - APU Fuel Line Chafing (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety 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 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.

Bombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes

AD/DHC-8/93 APU Fuel Line Chafing 11/2003

Applicability: DHC-8 Series 100, 200 and 300 aeroplanes, serial numbers 003 to 585 inclusive, with Auxiliary Power Unit (APU) installation per Standard Option Only (S.O.O.) 8155 or Change Request (CR) 849SO08155.

Requirement: Carry out the inspection and rectification (if required) of the APU fuel tube assembly, Part Number (P/N) 82830105-139, in accordance with Bombardier Service Bulletin (SB) 8-49-19, dated 13 May 2003, or SB 8-49-19, Revision A, dated 7 July 2003.

Note: Transport Canada AD CF-2003-22 refers.

Compliance: With six months from the effective date of this Directive.

This Airworthiness Directive becomes effective on 30 October 2003.

Background: Investigation of a fuel leak incident revealed chafing of the APU fuel tube assembly on the bleed air duct shroud located in the centre wing area. The APU fuel tube assembly is attached to a fairlead by two clamps. In some instances, incorrect installation of the clamps on the fairleads may result in insufficient clearance, and cause contact between the fuel line and the bleed air duct, or gust lock cable, resulting in chafing of the APU fuel tube. The intent of this Directive is to provide inspection instructions and corrective actions to ensure the integrity of the APU fuel tube.