On December 17, 1999, at 1024 hours Pacific standard time, a Cessna 172N, N738UA, operated by the pilot, was substantially damaged during a takeoff attempt at Concord, California. The airline transport rated pilot, the sole occupant, received minor injuries. Visual meteorological conditions prevailed for the personal flight operating under 14 CFR Part 91 and no flight plan was filed. The flight was destined for Napa, California. The airplane overran the departure end of runway 32L after attempting to takeoff with the control gust lock installed. After the accident the pilot stated to a Federal Aviation Administration inspector on-scene that he had failed to remove the control gust lock prior to the takeoff attempt. In the pilot's insurance company report he also stated that he failed to remove the gust lock during the takeoff roll. He said he reduced the throttle and over flew the airport fence and landed on a road near the runway. The pilot filed a partial Aircraft Accident Report without a statement.