On August 7, 2000, at 0735 central daylight time, a Brown/Morrison Rans S-12 unregistered amateur-built airplane was substantially damaged during takeoff from Jones Field, near Bonham, Texas. The pilot, who did not hold an FAA airman rating or a student pilot certificate, was the co-owner and operator of the airplane. The pilot and his passenger sustained minor injuries. Visual meteorological conditions prevailed for the 14 Code of Federal Regulations Part 91 personal flight, for which no flight plan was filed. The cross-country flight was originating at the time of the accident and was destined for the Gilmer-Upshur County Airport, near Gilmer, Texas. According to the pilot and the passenger, the airplane departed runway 35, and while climbing thru 800 feet AGL, encountered "gusty wind conditions." The pilot decided to return to the airport. He initiated a left turn toward the airport and encountered "a large gust of wind." The pilot applied full power; however, the airplane would not maintain altitude or airspeed. Subsequently, the airplane impacted a building and two unoccupied, parked vehicles. At 0650, the weather observation facility at the Grayson County Airport, near Sherman/Denison, Texas, (located 15 miles west of the accident site) reported the winds from 200 degrees at 6 knots, visibility 12 miles, scattered clouds at 10,000 feet, temperature 81 degrees Fahrenheit, dewpoint 68 degrees Fahrenheit, and altimeter 29.97 inches of mercury. The FAA inspector reported that the wing was folded upward and the composite propeller blades were separated from the propeller. The pilot reported that he accumulated a total of 15 flight hours, all of which were in the accident airplane.