According to the Transportation Safety Board of Canada’s (TSB’s) investigation report (A16P0069) published Aug. 28, loss of tail-rotor effectiveness (LTE) at low altitude led to the May 2016 helicopter crash near Prince George, British Columbia.
On May 4, 2016, a Highland Helicopters Bell 206B Jet Ranger III was conducting infrared scanning over a logged area about 112 nautical miles northwest of Prince George, with three people on board. Approximately seven minutes after starting scanning operations, the helicopter spun uncommanded to the right several times and hit the ground. The helicopter was destroyed on impact, and all the occupants were seriously injured. There was no post-impact fire.
The investigation determined that the combination of high gross weight and high power setting while the pilot was maneuvering at low speed, downwind, and out of ground effect (an altitude greater than half of the helicopter’s rotor diameter) put the helicopter in a flight condition that resulted in LTE. Loss of tail-rotor effectiveness is an uncommanded yaw rate that does not subside of its own accord, which if not corrected can result in the loss of control of the helicopter. It occurs when the tail rotor is not capable of providing adequate thrust to maintain directional control.
It was found that in this occurrence, the LTE occurred at a height above ground that did not give the pilot enough time to recover before the helicopter struck the ground.
See the investigation page for more information.
