AD/CL-600/87 Flap Failure (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-600/87 Flap Failure 11/2007

Applicability:

Bombardier Inc. Model CL-600-2B19 aircraft, serial number 7003 thru 7990 and 8000 and subsequent.

Requirement:

Action in accordance with Transport Canada AD CF-2007-10.

Compliance:

As detailed in Transport Canada AD CF-2007-10 with a revised effective date of
25 October 2007.

This Airworthiness Directive becomes effective on 25 October 2007.

Background:

On November 22, 2006, due to weather conditions a CRJ 100 executed a missed approach.  At the same time, a flaps malfunction resulted in the flaps becoming unresponsive while in the fully deployed position (45 degree).  The pilot declared an emergency and diverted to the alternate airport.  Due to high fuel consumption when flying in this configuration, the aircraft landed at a diversion airport with 512 pounds of fuel remaining.

Bombardier CL-600-2B19 aeroplanes have had a history of flap failures at various positions for several years.  Flap failure may result in a significant increase in required landing distances and higher fuel consumption than planned during a diversion.  The nature of the malfunction is related to the design and reliability of some of the components of the flap system.

To lower the risk of exposure until a permanent solution becomes available, this AD requires the implementation of the following four mandatory actions:

Part I:  AFM Change.  This action is mandated to provide the crew with additional guidance information for the FLAPS FAIL abnormal procedure, to address the possibility of fuel exhaustion resulting from a flaps failure at other than 0 degrees, in combination with a diversion to an alternate airport.

Part II:  Operational Procedures:  The operational procedures mandated herein are aimed at reducing or eliminating the risk caused by flaps failures.  These Operational Procedures cover the three most critical flaps failure modes.

Part III:  Training Procedures:  This action is mandated to provide personnel with training on the operational procedures of Part II of this directive and instruction on reduced or zero flap landing.

Part IV:  Maintenance Actions:  The maintenance actions are mandated to improve overall Flaps System reliability and bring the failure rate to an acceptable level, until permanent solutions are implemented.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

10 September 2007