What happened
The flight departed at 0151 CDT following a day of sightseeing and a night baseball game attended by the pilot and passenger. Prior to departure, the pilot received a weather briefing and filed an IFR flight plan. The forecast for the route included overcast skies with cumuliform clouds and rain showers; while widely scattered thunderstorms with moderate rainshowers were predicted, the pilot was not briefed regarding thunderstorm activity.
While en route, the pilot transmitted that his compass was "swinging." Shortly after this transmission, contact with the aircraft was lost. An in-flight breakup subsequently occurred, and wreckage was distributed over a wide area.
The investigation
Radar data indicated that the airplane performed rapid changes in altitude prior to the breakup. An examination of the wreckage revealed that both wings failed due to positive overload. Additionally, the stabilator failed downward and was bent aft before separating from the aircraft. The remaining portions of the aircraft sustained extensive damage from impact and fire.