On April 20, 1996, about 1005 eastern daylight time, a homebuilt Cox-Hawk, N7VC, registered to a private individual, was substantially damaged during a forced landing near Mebane, North Carolina. Visual meteorological conditions prevailed at the time and no flight plan was filed for the 14 CFR Part 91 personal flight. The commercial-rated pilot sustained serious injuries. The flight originated about 0945 from a private airstrip near Apex, North Carolina. The pilot stated that he did not obtain a weather briefing before takeoff. After departure during cruise flight between cloud layers with adverse weather ahead, he initiated a turn to perform a 180-degree turn to avoid the weather. The airplane which was not equipped with an attitude indicator or turn coordinator then entered clouds. The pilot further stated that the airplane began descending with the airspeed increasing beyond the designed never exceed speed(Vne). During the descent he felt buffeting through the airframe and observed that two of the six flying wires for the left wing were failed and the aileron flight control system was failed. The airplane emerged from the clouds about 1,300 feet above ground level and the pilot arrested the descent then selected a field for the forced landing. After touchdown in a rough field, the airplane cartwheeled and came to rest upright.