On July 15, 2004, at 1330 central daylight time, an experimental amateur-built Selby Dean KR-2-SS, N299DS, owned and piloted by a private pilot, received substantial damage on impact with terrain during final approach to runway 32 (2,850 feet by 75 feet, asphalt) at Lake Elmo Airport (21D), Lake Elmo, Minnesota. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 personal flight was not operating on a flight plan. The pilot was uninjured. The local flight originated from 21D at 1200. The pilot stated that he made two full stop landings at the airport prior to the accident approach. He noticed the winds buffeting slightly. At 50 feet above ground level, the right wing was hit with a severe updraft gust, almost inverting the airplane. He applied full power, and the left wing tip struck the ground. The wreckage was located about 100 yards from the approach end of runway 32. The St. Paul, Minnesota, Automated Surface Observing System, located 9 nautical miles southwest of 21D, recorded at 1253 - wind 270 degrees at 7 knots and at 1353 - wind 240 degrees at 7 knots. There were no wind gusts recorded on the day of the accident