Incident Overview
A helicopter conducting a low-altitude survey of utility equipment damaged by a recent wildfire encountered handling difficulties that culminated in a precautionary landing and collision with trees. The pilot reported that the helicopter was flying at an altitude of approximately 100 feet above ground level (AGL) at speeds between 40 and 60 knots while assessing wildfire damage.
Sequence of Events
While rolling out of a turn at 100 feet AGL, the pilot noticed a reduction in airspeed. As he applied forward cyclic and raised the collective to regain desired airspeed and altitude, he felt resistance on the controls. The helicopter responded by assuming a nose-high attitude. The pilot stated that a high power setting was required to maintain altitude. Subsequently, the helicopter began to yaw to the right, which the pilot attributed to the onset of loss of tail rotor effectiveness (LTE).
In response to the yaw, the pilot reduced power. The helicopter then started to descend. The pilot decided to execute a precautionary landing. During the landing, the helicopter impacted trees and came to rest on its left side.
Post-accident Examination
An FAA inspector responded to the accident site and examined the wreckage. The inspection revealed no mechanical anomalies with the helicopter or its control system.
Conclusion
The investigation did not identify a specific mechanical failure or other causal factor. The pilot's actions in response to the perceived loss of tail rotor effectiveness and the subsequent precautionary landing resulted in the helicopter striking trees.