On July 28, 2008, about 1930 central daylight time, an unregistered amateur-built Kolb Mark II airplane, sustained substantial damage when it had an in-flight loss of engine power and impacted tall vegetation during a forced landing near Chisholm, Minnesota. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight. The unlicensed pilot sustained serious injuries and one passenger sustained minor injuries. The local flight originated from a private airstrip near the accident. The pilot reported that he performed a preflight inspection of the airplane and saw that the fuel tanks were 90 percent full. He flew a 30-mile loop and landed. He did a quick visual inspection and saw that the fuel was about 50 percent full. He did not shut down the engine or get out of the airplane to perform that inspection. He then taxied and performed a normal takeoff. About 200 feet above ground level he encountered a loss of engine power. The engine continued to run and it produced "no power." The pilot elected to land straight ahead and impacted "small brush" and tall grass in a "swamp." The pilot reported no airplane mechanical malfunctions associated with the flight. He, in part, stated, "Did not determine cause of power failure but could possibly be prevented by doing more [thorough] inspection of aircraft."