On August 27, 1997, about 1950 eastern daylight time, a homebuilt Genesis, N9091B, was destroyed when it impacted after takeoff from a private grass airstrip near Columbia Station, Ohio. The certificated private pilot was fatally injured. Visual meteorological conditions prevailed for the local flight. No flight plan was filed for the personal flight conducted under 14 CFR Part 91. According to a witness, the pilot had flown the airplane only once before with another pilot, several months prior to the accident, and had not flown it since. Just before the accident, the pilot had performed several high speed taxi runs, with brief moments of flight just above the runway. The pilot had also shut down the engine three times to make adjustments to the carburetor with a screwdriver. The airplane was then observed to takeoff and climb at an angle steeper than normally used by the pilot. A second witness, who was sitting on his porch located 1/2 mile from the accident site, had noticed the airplane appear above the tree line to the east of his house. He noted that the airplane barely cleared the tree tops when it took off from the airstrip and looked to be moving abnormally slow. The airplane then appeared to enter a very tight left turn, appearing to return to the landing strip, then descend below the tree line. A third witness, who also lived 1/2 mile from the accident site, observed the airplane about 200 feet above the tree line. She noted that the airplane made a sharp turn to the left and nose down, then disappear below the tree line. A fourth witness located two houses north of the private grass strip, did report hearing the airplane's engine running until the sound of impact. A fifth witness, who was in his garage, across from the field where the airplane had taken off, stated that he could hear the engine sputtering, then stop running. The airplane came to rest nose down in a large, level field. The last several inches of both propeller blades were separated. Examination of the wreckage by a Federal Aviation Administration Inspector revealed that the engine was a two cycle, four cylinder, four carburetor engine. Attempts to run the engine were unsuccessful; however, the engine was rotated through the starter gear, and compression was obtained on all four cylinders. The carburetor for the number two cylinder was observed unsecured from its mount, and was free to move about 1/8 inch. According to his business partner, the pilot had just recently replaced all four carburetors. Fuel was observed in two of the three fuel tanks. Flight control continuity was established for all primary flight controls. There was no evidence of mechanical malfunctions with the airplane aside from the unsecured number two carburetor.