Accident Sequence
A Seair Seaplanes Beaver was departing Lyall Harbour, Saturna Island, British Columbia, for the water aerodrome at Vancouver International Airport. After an unsuccessful attempt at taking off downwind, the pilot took off into the wind towards Lyall Harbour. At approximately 1603 Pacific Standard Time, the aircraft became airborne but remained below the surrounding terrain. It turned left, then descended and collided with the water. Persons nearby responded immediately; however, by the time they arrived at the aircraft, the cabin was below the surface of the water. No signal from the emergency locator transmitter was heard.
Injuries and Occupants
There were 8 persons on board. The pilot and an adult passenger survived and suffered serious injuries. The condition of the other six occupants was not specified in the report beyond their presence on board.
Probable Cause (Official Findings)
The investigation identified the following causes and contributing factors: 1. The combined effects of atmospheric conditions and bank angle increased the load factor, causing an aerodynamic stall. 2. Due to the absence of a functioning stall warning system, in addition to the benign stalling characteristics of the Beaver, the pilot was not warned of the impending stall. 3. Because the aircraft was loaded in a manner that exceeded the aft CG limit, full stall recovery was compromised. 4. The altitude from which recovery was attempted was insufficient to arrest descent, causing the aircraft to strike the water. 5. Impact damage jammed 2 of the 4 doors, restricting egress from the sinking aircraft. 6. The pilot’s seat failed and he was unrestrained, contributing to the seriousness of his injuries and limiting his ability to assist passengers.
Additionally, the report noted several findings as to risk, including the risk of inadvertent stall when stall warning systems are unserviceable, the benefit of underwater egress training, the lack of alternate emergency exits, the need for explicit safety briefings on submerged egress, and the increased risk of drowning without flotation devices.