On September 29, 2001, at 1650 eastern daylight time, a homebuilt Preceptor-Ultra, N66VC, was substantially damaged during impact with terrain near Dublin, Virginia. The certificated private pilot and passenger were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight conducted under 14 CFR Part 91. In a telephone interview, the pilot stated that he departed the New River Valley Airport (PSK), Dublin, Virginia, about 1630, for a local sightseeing flight. On his way back to the airport, the pilot approached a mountain ridge at a 45-degree angle, "at the same altitude as the ridge." As he flew closer to the ridge, the airplane experienced a "modest downdraft," and the pilot added power to maintain his altitude. When the pilot noticed that he would not be able to climb over the ridge, he turned the airplane back toward the valley to regain altitude. He stated that during the turn, the airplane experienced a "substantial downdraft combined with windshear." The pilot added full power; however, the airplane's altitude continued to decrease at about 2,500 feet per minute, and the airplane impacted trees. The pilot further reported that he set the altimeter to the field elevation before he took off, which was 2,030 feet. He estimated his altitude in the turn was 400-500 feet above the trees. He normally flew to the airport at 1,000 feet AGL, and stated that if he would have flown at a higher altitude, about 3,000 feet, he would not have impacted the trees. The pilot stated there were no mechanical deficiencies with the airplane. Additionally, he stated that he obtained the winds prior to his departure, which were reported to be variable from 360 to 020 degrees, at 8 knots, gusting to 15 knots. A Federal Aviation Administration (FAA) inspector examined the airplane after the accident. According to the inspector, substantial damage was observed to the cowling, fuselage, and both wings. Flight control continuity was established from the cockpit to all control surfaces, and the engine was rotated 360 degrees by the propeller. A Safety Board Meteorologist conducted a search of pilot reports (PIREPs), in-flight advisories (AIRMETs), and winds aloft forecasts (FDs) issued for the surrounding area, on the day of the accident. According to the Meteorologist, no PIREPs or AIRMETs were issued around the time of the accident. Examination of upper air data revealed that the winds aloft in the vicinity of Greensboro, NC, at 1,000 feet, were from 020 degrees at 7 knots. The winds reported in the vicinity of Sterling, Virginia, at 1,000 feet, were from 010 degrees at 17 knots. Surface observations reported at PSK, at 1641, included winds from 330 degrees at 11 knots, gusting to 15 knots, 10 miles visibility, scattered clouds at 5,000 feet, temperature 17 degrees Celsius, dew point 6 degrees Celsius, and altimeter setting 30.15 in Hg. The pilot reported 697 hours of total flight experience, 153 of which were in make and model.