What happened
Shortly after 16:35 PDT, a Seneca III, registration C-GTOG, departed Teslin, Yukon, for a flight to Ponoka, Alberta. The aircraft, operated by a building contractor, was carrying the pilot and three passengers. After a takeoff roll of approximately 3,000 feet, the aircraft climbed to about 100 feet above the ground before entering a steep left turn and descending in a nose-down attitude. Witnesses observed the aircraft appearing unstable and flying at a very low speed before the impact. There were 4 fatalities in the accident.
The investigation
The investigation focused on the aircraft's weight, the state of the baggage door, and the mechanical condition of the locking mechanism. Investigators determined the aircraft was approximately 5,150 pounds at takeoff, which was 400 pounds over the maximum allowable takeoff weight of 4,750 pounds. This weight increase likely resulted in a higher stall speed and reduced climb performance.
Examination of the forward baggage door revealed that the key lock was in the unlocked position and the latch was unlatched. The key was found in the pilot's pocket. Disassembly of the lock showed that the key and tumblers were so worn that the key could be removed even when the lock was not in the fully locked position. Furthermore, the investigation found that the landing gear remained in the down position throughout the flight. While the engines were producing power at the time of impact, the open door created significant aerodynamic disturbances and served as a major distraction to the pilot.
Findings
- The aircraft entered an aerodynamic stall at an altitude too low for recovery.
- The aircraft was overweight by approximately 8% at the time of takeoff.
- The forward baggage door opened during flight because it was not properly secured.
- The worn condition of the baggage door key lock allowed the key to be removed while unlocked.
- The pilot's attention was likely diverted by the sudden opening of the door and the resulting noise and vibration.
- The extended landing gear further degraded the aircraft's performance.
Safety action
Following the investigation, the TSB issued a Safety Advisory to Transport Canada regarding the inspection of baggage door key locks. In response, Transport Canada has worked toward amending airworthiness directives or revising maintenance schedules to ensure these locks are function-checked during periodic inspections.