The experimental airplane was substantially damaged during a hard landing following a loss of engine power after takeoff on runway 25 (5,002 feet by 100 feet, dry asphalt). The accident occurred during the first flight of the amateur-built airplane. The pilot stated he had conducted over 4 hours of ground and taxi testing prior to the first flight. He noted that immediately prior to the accident takeoff he conducted a "high speed taxi run" and observed no problems with the engine. The pilot reported that during the takeoff roll the airplane accelerated to approximately 75 mph and lifted off "normally". He stated: "Within seconds of liftoff, the engine began "sputtering and slowing down." The "sputtering increased in intensity" and the pilot "realized that flight could no longer be maintained." He elected to execute an emergency landing in the grass area adjacent to the runway. He extended his glide in order to insure clearance to people located on the parallel taxiway positioned to assist in the event of an emergency. As result of the extended glide, the airspeed decayed and the airplane was "practically on a stall." He noted that the landing gear collapsed due to the resulting "rough landing" and the airplane subsequently "skidded to a halt" in the grass area near midfield. A post accident inspection did not reveal any anomalies associated with a significant loss of engine power. The engine had accumulated approximately 500 hours since overhaul.