AD/CL-600/72 Thrust Reverser Casades Configuration (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-600/72 Thrust Reverser Cascades Configuration 8/2007

Applicability:

CL-600-2C10 Regional Jet Series 700 Aircraft, Serial Numbers 10003 to 10116 inclusive.

Note 1:  Aircraft serial numbers 10002, 10117 and subsequent will have Service Bulletin No. 670BA-78-003 incorporated by Bombardier before initial delivery.

Requirement:

1.    For CL-600-2C10 Regional Jet Series 700 Aircraft Serial Numbers 10005 through 100040:

Perform an inspection of the thrust reverser cascades configuration, and correct the cascades installation if required, in accordance with Bombardier Alert SB A670BA-78-001, Revision A, dated 23 April 2002, or later NAA approved revisions.

2.    For all CL-600-2C10 Regional Jet Series 700 Aircraft, inspect the thrust reverser cascades configuration in accordance with Bombardier Alert SB A670BA-78-001 Revision A.

Note 2:  Transport Canada AD CF-2002-30R1 dated 22 June 2004 refers.

Compliance:

1.    Within 72 flight hours or 30 days following the effective date of this AD, whichever occurs first.

2.    Each time the thrust reverser cascade assemblies are changed.

This Airworthiness Directive becomes effective on 2 August 2007.

Background:

An incident occurred during a pre-delivery flight where upon landing and application of maximum thrust reverser, the aircraft veered to the right from the runway heading.

The investigation determined that the thrust reverser cascades configuration on the left engine was incorrect.  The cascades have different part numbers to control the correct installation location; however, it is physically possible that diagonally opposed cascades can be intermixed.

Bombardier has issued Alert Service Bulletin (SB) A670BA-78-001 to introduce an inspection and to confirm the proper installation of the thrust reverser cascades.

David Punshon
Delegate of the Civil Aviation Safety Authority

21 June 2007