What happened
During a night-time medical evacuation flight, a Beech King Air C90 was returning to Slave Lake, Alberta, after transporting a patient from Red Earth. The flight was being conducted under visual flight rules. As the aircraft approached runway 10, the pilot flying was unable to maintain alignment with the runway, prompting the captain to take control and initiate an overshoot maneuver.
During this turn, the aircraft moved away from the town lights and entered a layer of haze and mist. The crew lost all visual contact with the ground. While the aircraft was in a descending left turn, the radio altimeter activated to signal low altitude, but the pilots failed to react to the warning. The aircraft subsequently struck the snow-covered surface of Lesser Slave Lake.
Inside the cabin, the impact caused significant movement. An emergency medical technician, who was not restrained in his seat, was thrown into the center console. A four-year-old patient, who was lying on a stretcher without shoulder harnesses secured, was ejected from the stretcher and caught by the medical attendant. There were no serious injuries among the six people on board, though the aircraft sustained substantial damage.
The investigation
The investigation focused on the sequence of events leading to the loss of control and the lack of crew coordination. Investigators examined the cockpit environment, noting that the crew had not performed an approach briefing and had not communicated their specific tasks during the overshoot.
Technical reviews of the aircraft's maintenance and the weather conditions at Slave Lake were also conducted. The investigation looked into the training provided to the pilots, specifically regarding their ability to operate effectively in a two-pilot cockpit environment, as much of their experience was in single-pilot operations.