On July 12, 2002, at 2015 eastern daylight time, a homebuilt Zodiac CH 601-H, N422EZ, was substantially damaged when it collided with terrain during a takeoff at Weltzien Skypark (15G), Wadsworth, Ohio. The certificated private pilot/owner and the passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under 14 CFR Part 91. According to the pilot, he performed a preflight inspection, serviced the airplane with fuel, and taxied for takeoff from runway 21. The preflight run-up was "normal", and the airplane accelerated and lifted off as expected. However, after liftoff and acceleration in ground effect, the airplane would not climb. The airplane sank, struck the tail, continued off the departure end of the runway, crossed a road, and came to rest between trees. The pilot also stated that after the airplane started to sink, he pulled the yoke back and "got behind the power curve." During a telephone interview, a flight instructor at Weltzien Skypark stated that he was flying in the traffic pattern when the wind picked up from the north. He said the local policy was to use runway 21 when the wind was calm, and that runway 21 had been the active runway for most of the day. The flight instructor aborted a landing to runway 21 due to the tailwind. He reversed direction in the traffic pattern, announced the runway change over the UNICOM frequency, and configured the airplane for landing on runway 03 as the accident airplane taxied for departure from runway 21. When his airplane was on short final for landing on runway 03, the flight instructor advised the accident pilot to "hold short", because he was landing opposite the accident pilot's intended direction of takeoff. After landing, the flight instructor told the accident pilot that "the new active runway is 03," and the accident pilot thanked him for the advisory. It surprised the flight instructor when the accident pilot took off from runway 21. The flight instructor saw the other airplane pass by him about 4 feet off the ground, with a 70-degree nose-high attitude. The pilot held a private pilot certificate with a rating for airplane single engine land. His most recent Federal Aviation Administration (FAA) third class medical certificate was issued May 7, 2002. The pilot reported 384 hours of flight experience, 282 hours of which were in the accident airplane. The pilot built the accident airplane. He registered it in the experimental category, and was issued an FAA airworthiness certificate on September 22, 1995. When questioned about the performance and handling of the airplane, the pilot said that it seemed to be running without any problem. He mentioned that it usually gets off the ground and it climbs out in a normal manner. He added that this time, the wind had changed, and he went off the east side. The pilot didn't think the winds were that much of a factor but added that maybe what happened was his fault. The weather recorded at an airport 10 miles south of Wadsworth included winds from 330 at 6 knots. The weather recorded at an airport 15 miles east of Wadsworth included winds from 080 degrees at 6 knots.