What happened
An analysis of 1,432 seaplane accidents occurring in Canada between 1976 and 1990 revealed a significant pattern of fatalities during water-based operations. In a subset of 103 fatal accidents where the aircraft ended up in the water, the survival rate was alarmingly low, with less than 10% of the 276 occupants managing to escape the aircraft unhindered. While many accidents occurred during the take-off or landing phases, the primary threat to life was not the initial impact, but the period following the crash.
The investigation
The TSB examined 103 specific accidents that resulted in 168 deaths to determine why occupants were unable to survive. The investigation focused on the causes of death, the effectiveness of restraint systems, and the accessibility of life-saving equipment. The Board reviewed autopsy data and accident records to distinguish between deaths caused by impact forces and those caused by post-impact drowning. The study also looked at the physical state of the aircraft, such as whether the fuselage had buckled or if the aircraft had flipped upside-down, which could obstruct exits.
Findings
Data from the 168 fatalities showed that drowning was the primary cause of death, accounting for 67% of all victims. Only 11% of deaths were directly attributed to the force of the impact itself. The investigation found that many occupants were trapped inside the cabin, with 70% of the deceased located within the aircraft. Several factors contributed to this high mortality rate:
- Inadequate Restraints: There was a notable lack of use of shoulder harnesses. In cases where data was available, 68% of pilots were not using available harnesses, and many passengers also failed to utilize them. The lack of upper-torso restraint increased the risk of head trauma and loss of consciousness.
- Egress Obstructions: Impact forces often caused the aircraft fuselage to buckle, jamming doors or opening mechanisms. In some instances, aircraft flipped onto their backs, making it difficult for occupants to maintain situational awareness or find exits.
- Life Jacket Accessibility: While life jackets were often carried on board, they were frequently difficult to reach in an inverted or submerged aircraft. In some cases, occupants even drowned while attempting to swim back to the aircraft to retrieve stowed life jackets.
- Lack of Briefings: Many passengers were unfamiliar with the aircraft's emergency procedures, egress routes, or the location of safety equipment, as pre-flight safety briefings were not consistently implemented.