A sudden turn by the pilot of a survey helicopter likely caused an interruption fuel flow to the engine, resulting in a fatal crash near Whitecourt, Alberta in September of 2016 according to the Transportation Safety Board report.
One of two surveyors on the aircraft was killed when the helicopter dropped 160 feet into trees. The pilot was seriously injured and another surveyor had minor injuries.
The report was released this week and said the pilot allowed the fuel level in the Bell 206B to drop below a quarter of a tank and a quick turn likely briefly cause fuel to slosh away from one or both of the boost pumps, allowing air into the fuel line and causing the flameout.
The helicopter was equipped with an after market automatic restart system but the system was turned off at the time of the crash.
The TSB said the aircraft operator, Ridge Rotors Inc., has since required the relight system to be left on during all phases of flight and the pilots “have been trained accordingly.”