AD/CL-600/101 Main Landing Gear Trunnion Fitting Web (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-600/101 Main Landing Gear Trunnion Fitting Web 9/2008 DM

Applicability:

All Model CL-600-2B19 aircraft.

Requirement:

1.    Revise the Transport Canada approved maintenance schedule by incorporating the new inspection requirements of Airworthiness Limitations (AWL) Number 57-21-161, as introduced by Temporary Revision (TR) 2B-2136 of the Canadair Regional Jet Maintenance Requirement Manual (MRM), Appendix B, “Airworthiness Limitations”.

2.    Initial compliance with the new AWL task shall be carried out in accordance with the applicable Phase-In Schedule detailed in TR 2B-2136 of the MRM.

Note:  Transport Canada AD CF-2008-21 refers.

Compliance:

1.    Within 30 days after 25 June 2008, unless already accomplished.

2.    As specified in Requirement 2.

This Airworthiness Directive becomes effective on 25 June 2008.

Background:

Cracks in the main landing gear trunnion fitting web have been discovered during fatigue testing.  Failure of the trunnion fitting web could compromise the structural integrity of the trunnion fitting and result in a main landing gear collapse.  A TR has been made to the CL-600-2B19 MRM to ensure that fatigue cracking of the trunnion fitting web is detected and corrected.

David Villiers
Delegate of the Civil Aviation Safety Authority

20 June 2008