Weather Briefing and Departure
At 1433 CDT, the pilot received a weather briefing advising of 500-foot ceilings, 2-mile visibility, rain showers, and thunderstorms. Despite these conditions, the pilot departed from Bismarck, Missouri, without filing a flight plan.
In-Flight Weather Encounter and Crash
During the flight, the pilot encountered weather that deteriorated as the route progressed. The aircraft subsequently crashed inverted in a corn field near Raymond, Illinois. A witness reported seeing the aircraft "going or spinning straight down" but did not observe the actual crash.
Structural Failure Findings
An investigation revealed that the outer 4-foot section of the left wing and the left aileron had separated in flight. Evidence indicated that the separation occurred upward and aft, with no signs of fatigue or corrosion at the fracture area. The right wing tip also failed but remained attached to the aircraft.
Weather Conditions
According to an NTSB weather summary, cloud bases were approximately 700 feet above ground level (AGL), with cloud tops reaching about 14,000 feet mean sea level (MSL). About 50 miles northeast at Decatur, Illinois, a 2,000-foot overcast was reported.
Aircraft Instrumentation
The aircraft was not equipped with a certified turn-and-bank indicator or attitude indicator.