Sudden onset of a heavy snow shower possibly a factor in the incident, says TSB
The pilot’s sudden loss of visual references due to rapidly deteriorating weather conditions led to a helicopter crash that injured four people in Quebec nearly two years ago, according to a new report from the Transportation Safety Board of Canada (TSB).
The incident happened on April 7, 2023, when the Bell 206L helicopter was flying in Port-Cartier.
At around 8:20 Eastern Daylight Time that day, the aircraft flew from the ArcelorMittal facility, bound for the company's Fox Camp located along the railway, 49 nautical miles northwest of Port-Cartier.
One pilot and three passengers were on board the flight.
Although the weather forecast did not indicate any concerning conditions, the weather unexpectedly deteriorated mid-flight. Snow showers and a rapidly lowering ceiling resulted in significantly reduced visibility.
While flying over a small lake connected to the northern portion of Vallilée Lake, the pilot suddenly lost all forward visual references.
He executed a right turn where he could see trees on the eastern shore. During the turn, however, he lost his visual references momentarily, but regained them just before the helicopter struck the frozen surface of the lake.
“One of the risks of continuing a [visual flight rules] (VFR) flight in [Instrument meteorological conditions] (IMC) is the sudden loss of visual references,” said the TSB.
“In this case, spatial disorientation would lead to loss of control of the aircraft if appropriate actions are not taken immediately. This is an emergency situation that any pilot can find themselves in, regardless of their experience.”
According to the TSB, the pilot of the Bell 206L helicopter believed he could detect the imminent loss of visual references and turn back or land before the situation arose. However, approximately 5 seconds after beginning the crossing of the snow-covered lake, the pilot suddenly lost all his forward visual references, most likely due to the sudden onset of a heavy snow shower, reported TSB.
Source: Transportation Safety Board of Canada (TSB)
The pilot and three passengers suffered minor injuries but survived the crash.
What safety measures are in place to prevent helicopter accidents?
Following the incident, Canadian Helicopters Limited – Hélicoptères Canadiens Limitée—the operator of the helicopter—took the following safety measures, according to TSB:
- Several articles have been published in the company newsletter regarding impacts without loss of control, the tendency to stick to the plan and the tendency to anticipate.
- The flight operations manager has issued a clarification note regarding the company's weather limitations.
- An operations and safety update meeting for all company personnel was held on June 22, 2023. During this meeting, several topics directly related to this event were discussed.
- The accident studied in this report now serves as an example in initial and annual training on operations in reduced visibility in order to raise awareness among pilots and encourage them to exercise vigilance.
- The United States Helicopter Safety Team's "56 Seconds to Live" video on inadvertent flight into instrument meteorological conditions has been incorporated into all pilot training. In addition, a new section on whiteout has been added to the training.
- The specific sections of the Company Operations Manual governing daytime visual flight rules operations in reduced visibility and weather limitations have been reviewed, amended and submitted for Transport Canada approval.
- Lessons learned from this event were shared with all relevant stakeholders.
