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In its investigation report released on Oct. 25, the Transportation Safety Board of Canada (TSB) found that low altitude and the speed at which a private helicopter was flown caused it to crash into the Restigouche River after colliding with transmission cables in September 2016 near Flatlands, N.B.
On the afternoon of Sept. 4, 2016, a privately operated Bell 206B helicopter departed Charlo Airport, N.B., for Rivière-du-Loup Airport, Que., with a pilot and two passengers on board. While flying along the Restigouche River, the helicopter collided with and severed power transmission cables that spanned the river at a height of 18 metres above the water. The aircraft was catastrophically damaged and subsequently fell into the river. The pilot and front-seat passenger were fatally injured. The rear-seat passenger survived the accident and bystanders helped him to shore.
The investigation concluded that the low altitude and the speed at which the helicopter was flown made the unmarked transmission cables difficult to see and avoid. It is likely that the pilot was unaware of the power transmission lines spanning the river, and that he did not see them before the helicopter struck them.
Intentional low-altitude flying is risky, particularly without pre-flight planning and reconnaissance, and may result in a collision with wires or other obstacles, increasing the risk of injury or death. After the accident, Transport Canada determined that the power transmission lines spanning Restigouche River at Flatlands-Long Island did not require lighting or marking.
In addition, there were physiological factors that had the potential to degrade the pilot’s decision-making and performance, although their specific effects on the pilot could not be determined. The investigation found that the pilot had limited opportunities to sleep prior to the flight, and he was likely experiencing acute fatigue at the time of the accident. If pilots do not take advantage of opportunities to sleep between duty periods, there is an increased risk of degraded performance due to fatigue.
A post-mortem toxicological exam performed on the pilot also revealed the presence of cannabinoids in his system. Conclusions regarding impairment, or the time at which the cannabinoids were used, could not be made. Flight crew members who use cannabinoids risk impaired performance and decision-making, jeopardizing the safety of the flight.
The helicopter was equipped with an emergency locator transmitter (ELT). However, the search and rescue satellite system did not receive a signal from the helicopter’s ELT. The investigation determined that the ELT activated, but its antenna broke off and the ELT sank into the river, which made its detection impossible.
The Board issued four recommendations in 2016 (recommendations A16-02, A16-03, A16-04 and A16-05) to address deficiencies in ELT design standards that may delay search and rescue operations after an accident. International collaboration is now underway to improve ELT specifications.
