Accident Narrative
A helicopter was departing from a confined area when the pilot reported a power loss during takeoff. According to the pilot, the aircraft rose to 50 feet above ground level (AGL) at 90 percent torque. It then continued to climb to 200 feet AGL, though the pilot could not recall the power settings at that point. Upon reaching 200 feet AGL, the pilot nosed the aircraft over to accelerate and initiated a left bank, applying approximately 20 degrees of bank angle. The pilot then felt the aircraft shudder, and it began to settle. He added power, and the low rotor RPM audio and light warnings activated. During the subsequent descent, the pilot observed that the N2 RPM was decreasing and passed through 90 percent; he lowered the collective, and the N2 RPM stabilized at 80 percent. The pilot stated that he attempted to regain rotor RPM by "pumping" the collective, but this was unsuccessful, and the aircraft crashed into marshy terrain.
Investigation Findings
Examination of the wreckage and subsequent testing did not reveal any mechanical reason for the power loss. No other causal factors were identified in the investigation.