What happened
On 15 June 2009, a privately operated Beechcraft V35B Bonanza, registration C-GWUW, departed Edmonton City Centre Airport for a visual flight rules (VFR) excursion to view the Badlands near Drumheller, Alberta. The pilot had communicated a flight itinerary to family members but did not file a formal VFR flight plan with NAV CANADA.
Radar tracking monitored the aircraft as it traveled south through Camrose and Bashaw, maintaining altitudes between 4,000 and 4,600 feet. By 12:49, the aircraft appeared on Medicine Hat radar, flying at approximately 160 knots. Shortly thereafter, the aircraft entered an extreme nose-down attitude. The aircraft struck the ground in a near-vertical descent in a lightly wooded area near Castor, Alberta. The impact was so severe that the engine and forward fuselage embedded several feet into the earth. The sole occupant of the aircraft, the pilot, sustained fatal injuries.
Because there was no visible smoke or sound of impact reported by bystanders, the aircraft was not located until the following day, 16 June 2009, after a search was initiated by the pilot's family.
The investigation
The investigation focused on the aircraft's mechanical condition and the flight path leading to the impact. Investigators examined the wreckage and found that the engine, propeller, and flight control surfaces showed no evidence of catastrophic mechanical failure or structural malfunction prior to the crash. The landing gear and flaps were in the retracted position at the time of impact.
Research into the handling characteristics of the Beechcraft V35B Bonanza indicated that the model has a tendency to enter a spiral dive if the pilot or autopilot fails to maintain wing levelness. Once a bank angle is established, the aircraft's lateral stability is insufficient to recover, leading to increasing bank, pitch, and airspeed.
Findings
- For undetermined reasons, the aircraft departed controlled flight and crashed in an extreme nose-down attitude.
- The pilot had not filed a VFR flight plan, which contributed to the delay in locating the wreckage.
- The high-energy, 90-degree impact angle suggests the aircraft may have entered a spiral dive that progressed to a vertical descent, making recovery unlikely at such a low altitude.