According to the pilot's accident report, when he attempted to start the engine the starter motor turned but the starter did not engage. The pilot made additional attempts to start the engine with the same result. The pilot turned off the battery master switch, got out and walked around to the front of the airplane. He reached through the door and thought the ignition key was off. He pushed the propeller down through one compression stroke. The engine immediately started. The pilot jumped on the left wing, but fell off. The airplane traveled across the ramp and struck a ditch between runways 28R and 28L, breaking off the nose gear and buckling the firewall. An examination of the airplane and its systems, conducted by the Federal Aviation Administration, revealed no anomalies.