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. Bombardier (Canadair) CL-600 Series Aeroplanes AD/CL-600/51 Chafed IDG Cables 5/2002 DM Applicability: CL-600-2B16 "Challenger" aircraft as follows: CL-600-2B16 (CL-601-3R) serial numbers (S/N) 5135 through 5194 inclusive; and CL-600-2B16 (CL-604) S/N 5301 through 5481 inclusive. Requirement: 1. Unless previously accomplished, visually inspect the integrated drive generator (IDG) cables for both left and right engines for chafing and damage between the service pylon connections to the IDG in accordance with the Accomplishment Instructions of the applicable Bombardier Alert Service Bulletin (ASB) below: 1. CL-600-2B16 (CL-601-3R) aeroplanes - ASB A601-0542 dated 12 January 2001; or b. CL-600-2B16 (CL-604) aeroplanes - ASB A604-73-002 dated 12 January 2001. 2. If chafing or damage is detected, repair as follows: 1. If the inner core of the cable is not visible and not damaged, install a repair or replace the damaged IDG cable in accordance with ASB A601-0542 or ASB A604-73-002 as applicable. b. If the inner core is visible or damaged, replace the damaged IDG cable. Bombardier (Canadair) CL-600 Series Aeroplanes AD/CL-600/51 (Continued) 3. Install protective Teflon tubing and additional clamp hardware on the IDG cable harness in accordance with ASB A601-0542 or ASB A604-73-002 as applicable. Note: Transport Canada AD CF-2001-06 refers. Compliance: Requirement 1 - Within 50 hours time in service (TIS) after the effective date of this Directive. Requirement 2 - Before further flight after the Requirement 1 inspection. Requirement 3 - Within 400 hours TIS after the effective date of this Directive. This Airworthiness Directive becomes effective on 10 April 2002. Background: Transport Canada has advised that a report has been received from a CRJ-100 operator of electrical arcing between the IDG cable and an engine cowl door due to IDG cable chafing. The IDG cable installation in the Challenger model is similar to that of the CRJ-100. This arcing condition, if not corrected, could potentially be an ignition source of an in-flight fire and/or result in the in-flight loss of generated electrical power. Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority 3 April 2002 The above AD is notified in the Commonwealth of Australia Gazette on 10 April 2002.