NTSB Factual Report

On April 4, 2008, at 1503 central daylight time, a Hiller UH-12E, N40289, registered to and operated by Ascent Aviation, was substantially damaged when it struck the ground while maneuvering and rolled over at La Porte Municipal Airport (T14), La Porte, Texas. Visual meteorological conditions prevailed at the time of the accident. The test flight was being conducted under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 without a flight plan. The airline transport certificated pilot received minor injuries, and his pilot certificated passenger was not injured. The local flight originated at T41 approximately 10 minutes before the accident.

According to the pilot's accident report, he was test flying the helicopter after performing some maintenance that had been requested by its new owner. He performed two "quick stop" maneuvers into the wind. After completing the quick stop maneuver and while in a 5-foot hover, he initiated a slow pedal turn to the left to return to the hangar. As he began the turn, he noticed "a loss of control effectiveness" and he attempted to set the helicopter down. Before he could regain control, the helicopter "slammed" into the ground. The pilot said it had begun to rain and after he exited the helicopter, he noticed the wind sock had shifted 180 degrees. The tail boom was severed and the main rotor blades were destroyed.

NTSB Probable Cause

The loss of tail rotor effectiveness. Contributing factors were the sudden windshift to a tailwind, and the pilot initiating a hovering turn in ground effect.