Air Transport

Bombardier has identified a correlation between the specific demands of extreme cold weather conditions and the spike in CRJ flap failures, and is working on a corrective plan of action.

Already in the middle of a comprehensive review of the CRJ's flap system, the Canadian manufacturer says it has determined that the increase in flap failures - highlighted last week in a Transportation Safety Board (TSB) notice - is "very much related to winter weather" and that "cold-country operators are affected".

The airframer says the problem is not a design issue where entire systems need replacing, but rather involves some components that are "not as responsive as they should be". It adds that there is "no risk to passenger safety".

The manufacturer is "already investigating the root causes with our operators in order to really implement a corrective plan of action". The short-term action plan involves implementing a preventive screening programme and expanding maintenance procedures that address the specific demands of winter operations.

Canada's TSB expressed concern over an increasing number of flap failures in the CRJ fleet and is requesting that minister of transport Lawrence Cannon issue advice on the agency's next steps for addressing the problem.

The request comes in the wake of a 21 November incident involving an Air Canada Jazz CRJ200ER that was cleared for a non-precision approach at Prince George, British Columbia. While established on final approach, and with the aircraft configured for the landing with flaps set at 45°, the flightcrew conducted a missed approach. However, the flaps did not retract when selected, remaining at 45°. The flightcrew ultimately decided to divert to Fort St John, British Columbia.

En route they attempted to recycle the flap circuit breakers, but this did not clear the fault. The aircraft landed without further incident.

The TSB also notes that a statistical review of its database of reported flap events since 2005 "indicates an ever-increasing number of flap failures experienced by CRJ aircraft".

But Bombardier says these events do not resemble the Jazz incident, which "is the first reported incident involving flaps failing to retract at 45°", and that "a result of a combination of events" conspired to make this incident "very unusual".
Since its occurrence, Bombardier has "continued to work and co-operate closely with the TSB and regulatory authorities to offer assistance as required", he says.