What happened
During a test flight, the pilot and co-pilot were performing practice autorotations. While executing their seventh autorotation at an altitude of approximately 100 feet above the ground, the engine lost power. The crew continued the autorotation procedure, but reported encountering a downdraft during the maneuver.
The resulting hard landing caused substantial damage to the helicopter.
Weather conditions at the time of the accident varied by report. The control tower recorded winds from a magnetic bearing of 240 degrees at 15 knots, with gusts reaching 30 knots. However, in a written report provided by the pilot, the winds were described as being from a magnetic bearing of 230 degrees, variable to 270 degrees, at 23 knots with gusts up to 35 knots. The manufacturer's flight manual specifies that controllability is adequate in 20 mph winds from any direction.