Accident Sequence
During an approach at an altitude of approximately 150 to 200 feet above ground level, the helicopter began to rotate clockwise about the nose in a nose-down attitude. The descent continued, and the helicopter landed hard in a level attitude, causing the landing skids to collapse. Subsequently, the helicopter rolled over onto its right side, and the main rotor blades struck the ground.
The pilot reported making a wide right turn to align with the landing area when the nose yawed right by about 45 degrees. The helicopter then rotated twice despite the pilot's attempt to correct with full left pedal application and reduced collective pitch. The pilot stated that the engine appeared to be operating at full power after the collision.
Investigation Findings
The investigation did not disclose evidence of mechanical malfunction. Based on data from the U.S. Army and Bell Helicopter, the combination of airspeed and wind conditions present during the event were conducive to the occurrence of a loss of tail rotor effectiveness.