The Transportation Safety Board of Canada has released their findings into the investigation of a plane crash that occurred while fighting the wildfire near Cold Lake in May of 2015.
Authorities conclude that the aircraft encountered a fire whirl, which led to a loss of control and a crash into the ground. The 38-year-old pilot William Hilts died on impact.
A number of factors such as a large heat source, unstable atmosphere, and low winds can cause a fire whirl, which is basically a burning tornado. Investigators determined the pilot would not have been able to see it from where he was and would not have anticipated it being in the flight path.