On August 13, 2005, at 1115 eastern standard time, a Robinson R44, N534SE, piloted by a commercial pilot, received substantial damage on impact with terrain during landing at Greenwood Municipal Airport (HFY), Greenwood, Indiana. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 revenue sightseeing flight was not operating on a flight plan. The pilot and two passengers received minor injuries. The local flight originated from HFY at 1110. The pilot was providing helicopter rides at the "HFY Open House," and the accident flight was about the pilot's 10th flight of the day. The pilot stated that when the helicopter was over the landing area, the forward ends of the skids contacted the ground with a "very small amount of forward motion." He stated that when the forward motion stopped, a reduction in collective was started and then an abrupt pitch oscillation began. The pitch oscillation increased and he tried to increase collective to lift the skids off the ground. The nose pitched down "violently" and the main rotor blades contacted the ground in front of the helicopter. The helicopter rolled onto its right side as the nose yawed left 90 degrees. Inspection of the helicopter by the Federal Aviation Administration revealed no anomalies that would have precluded normal operation.