On August 15, 1999, at 1131 eastern daylight time, a Robinson R-22 Beta helicopter, N4066G, was substantially damaged during landing at the Long Island MacArthur Airport (ISP), Islip, New York. The certificated flight instructor (CFI) and the student pilot were not injured. Instrument meteorological conditions prevailed for the local instructional flight that originated at ISP, approximately 1045. No flight plan was filed for the flight conducted under 14 CFR Part 91. In a telephone interview, the CFI said the purpose of the flight was to demonstrate hovering autorotations to the student pilot. The student pilot was to learn the maneuver and then practice the autorotation from a hover. The CFI said they had practiced the maneuver for 45 minutes prior to the accident. He said: "We were in the sod practicing hovering autorotations. Closing the throttle, pushing right pedal, and cushioning the landing with collective. We did it about 10 to 15 times. At first I was on the controls with her, but as a flight instructor, I have to give her more and more responsibility." The flight instructor said the student pilot was flying the helicopter and that he was monitoring the flight controls when the student pilot initiated the maneuver from a 4-foot hover. He said: "She pushed left pedal instead of right pedal. We did a left yaw, approximately 60 degrees, touched down on the left skid first, and then rolled over to the left. There's no mystery; it's totally pilot error. She knows what happened but I, as the instructor, am responsible." In a written statement, the CFI said, "I ...tried to abort by rolling on throttle and lifting up." In a telephone interview, the student pilot stated the purpose of the flight was to perform autorotations from a hover. She stated she had never done a hovering autorotation, and needed to learn and perform the maneuver before she could fly the helicopter solo. She said: "We were practicing hovering autorotations and it was my first time. The first time, [the CFI] did it. The next few, [the CFI] did them with me. He was on the controls with me. The last few I did myself." The student pilot said she initiated the maneuver when she announced, "Engine failure 1, 2, 3..." and closed the throttle. She said: "I entered the autorotation and I did not slam sufficiently hard on the right pedal because we yawed pretty badly to the left. We landed on the left skid and we bounced up. I noticed the collective was up, so I think I slammed it down. Then we landed back on the left skid and teetered for a second. I thought we could go either way but we rolled left and the blades hit the ground." When questioned about the handling and performance of the helicopter, the student pilot reported: "The helicopter was performing fine, totally fine. It certainly wasn't the helicopter's fault." In a written statement, the pilot reported there were no mechanical deficiencies with the helicopter. The instructor said the student pilot began flight training on March 7, 1999. He said she flew nearly every weekend and averaged approximately 1 1/2 flight hours per week. The student pilot said she had accrued 30 hours of flight experience during that time, all of which was in the R-22. The CFI reported 472 hours of flight experience, of which 218 hours were in the R-22. According to the Robinson R-22 Safety Notice #9: "Hovering autos are particularly susceptible to dynamic roll-over. If the student allows the ship to touch down while drifting sideward and, and at the same time, is late pulling in collective, he is likely to have a dynamic roll-over. The skid hitting sideways starts the roll over and the late application of collective pulls the ship over past the point of no return." Winds at ISP at the time of the accident were from 010 degrees at 11 knots.