On November 2, 1998, at 1100 hours mountain standard time, a Cessna 185E, N185Z, ground looped and departed runway 11L on the takeoff roll at the Tucson, Arizona, airport. The aircraft sustained substantial damage. The airline transport pilot, the sole occupant, was not injured. Visual meteorological conditions existed for the personal flight operated under 14 CFR Part 91, and no flight plan was filed. The pilot reported that as he was on the takeoff roll his seat slid out of the detents. He stated that "this pulled my feet off the rudder pedals and my hands off the controls." The pilot reported that the aircraft made a turn to the left as he was attempting to move the seat forward to regain use of the rudders or the brakes. He reached up to retard the throttle and the aircraft came to a stop after a ground loop. No further mechanical malfunctions were noted with the aircraft. According to a Federal Aviation Administration (FAA) airworthiness inspector who examined the aircraft at the airport, the seat was stiff and was difficult to move fore and aft. He reported that the detents in the seat rails did not show any signs of wear, and the pilot may have thought he had the seat locked into place because of the stiffness of the seat. The FAA did note that the aircraft was 40 hours out of annual, but that the condition of the seat and seat rails would have passed an annual inspection.