What happened
On a night instrument flight rules (IFR) mission, a corporate aircraft departed Calgary International Airport, Alberta, bound for Hillsboro, Oregon. The flight, carrying a pilot and four passengers, was intended to return company personnel to the United States following a business meeting. During the flight, the aircraft disappeared from radar at the Vancouver Area Control Centre near Castlegar, British Columbia, at approximately 19:46 MST.
Following a seven-day search operation, wreckage was discovered on June 14, 1996, at an elevation of roughly 6,700 feet. The impact and subsequent fire destroyed the aircraft, and all five occupants were killed. The investigation revealed that the aircraft struck the terrain in a steep, nose-down attitude with its landing gear and flaps retracted.
The investigation
Investigators examined radar data, engine performance, and weather briefings to reconstruct the flight's final moments. While the aircraft's speed, altitude, and track remained steady during the en route portion, radar showed a significant drop in ground speed from 140 knots to 90 knots in the five minutes preceding the crash.
Engine examinations determined that the engines were capable of producing power and were functioning at approximately 2400 rpm during the early stages of the flight. Although the pilot had aborted an initial takeoff in Calgary due to a right engine RPM issue, there was no evidence of mechanical failure or engine incapacity during the final descent. Additionally, no evidence of airframe failure or systems malfunction was found, and the state of the remains prevented toxicological analysis of the pilot.
Findings
- The aircraft may have departed with a take-off weight exceeding the allowable limit.
- The area forecast had predicted a probability of severe clear icing in freezing drizzle along the route, but this specific information was not provided during the pilot's weather briefing.
- The aircraft entered a precipitous, uncontrolled descent from which the pilot was unable to recover.
- While the exact reason for the sudden descent remains undetermined, the pilot chose to fly through an area where severe icing was forecasted.