What happened
On 21 November 2006, an Air Canada Jazz CL-600-2B19, registered as C-GJZF, was operating a scheduled passenger flight from Vancouver to Prince George, British Columbia. During the approach to Prince George Airport, the flight crew received weather updates indicating conditions had dropped below landing minimums. While attempting the approach on Runway 33, the crew configured the aircraft for landing; however, upon reaching the final approach fix and initiating a missed approach, they discovered the flaps were stuck at 45 degrees.
The mechanical malfunction significantly increased the aircraft's drag. The crew initially diverted toward Grande Prairie, Alberta, but due to rapidly increasing fuel consumption, they requested a diversion to Fort St. John. At 1537, the crew declared an emergency due to a low fuel prediction. The aircraft landed at Fort St. John at 1616 with approximately 500 pounds of fuel remaining, representing less than 10 minutes of flight time. There were no injuries among the 49 passengers and 3 crew members.
The investigation
The investigation examined the mechanical state of the flap system and the maintenance history of C-GJZF. It was established that water ingress into the flap actuators, combined with cold temperatures, was a primary driver of the failure. Maintenance records revealed that water had been extracted from the actuators during a previous greasing process.
Investigators also reviewed the crew's decision-making and the limitations of the Quick Reference Handbook (QRH). While the QRH provided instructions for landing with flaps at 45 degrees, it did not account for the performance penalties—specifically regarding climb rate and fuel burn—during a missed approach. Furthermore, the investigation found that the maintenance documentation lacked consistency, which hindered the timely identification of the faulty actuators.