Incident Overview
A helicopter conducting an aeromedical evacuation of a seriously injured patient attempted to take off from a clearing that was surrounded by trees and high-elevation terrain. On board were the pilot, a paramedic, and a flight nurse. According to crewmembers, as the helicopter climbed between 80 and 100 feet above the terrain, no tree branches were closer than 8 to 20 feet from the aircraft.
Sequence of Events
After takeoff, the pilot initiated a turn into the light wind. During this maneuver, the tail rotor lost effectiveness, causing the helicopter to yaw uncontrollably in a clockwise direction. Concurrently, the aircraft experienced a lack of climb performance due to the high density altitude—approximately 8,850 feet—and the heavy weight condition resulting from the patient, crew, and equipment.
Forced Landing
Unable to maintain controlled flight, the pilot executed a forced landing into the underlying terrain. During the landing, the helicopter impacted trees. The source does not specify further details about the outcome of the impact or the condition of those on board.
Factors
The incident involved a combination of environmental and operational conditions, including high elevation, surrounding trees, light wind, and the weight of the helicopter. The tail rotor's loss of effectiveness and reduced climb performance were noted as central to the event.