AD/CL-600/122 Thrust Reverser Transcowl Assembly (Cth)

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 39.001(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 (Canadair) CL-600 (Challenger) Series Aeroplanes

AD/CL-600/122 Thrust Reverser Transcowl Assembly 12/2009

Applicability:

Model CL-600-2C10 aircraft, serial numbers 10003 through 10265.

Model CL-600-2D15 and CL-600-2D24 aircraft, serial numbers 15001 through 15192.

Requirement:

Action in accordance with the requirements of Transport Canada AD CF-2009-33.

Compliance:

As specified in the Requirement document.

This Airworthiness Directive becomes effective on 19 November 2009.

Background:

Several cases have been reported of cracks in the joint extrusions securing the outer bondment to the acoustic panel of the nacelle transcowl assemblies.  Although there is no effect on flight safety (thrust reverser stowed), thrust reverser deployment under rejected take-off or emergency landing load conditions could potentially result in acoustic panel failure and possible runway debris.

David Villiers
Delegate of the Civil Aviation Safety Authority

28 September 2009