Incident
While at cruising altitude, the pilot encountered poor weather conditions including rain, turbulence, and thunderstorm activity. The flight was being conducted under visual flight rules (VFR) mode. The pilot subsequently lost control of the airplane, which entered a dive. During the dive, the aircraft experienced an in-flight failure. It then crashed inverted into water near Walnut Grove. All six occupants aboard were killed in the accident. Flight service specialists (FSS) had not recommended VFR flight for the conditions.
Investigation Findings
Investigators determined that the pilot continued VFR flight into adverse weather conditions. The pilot suffered spatial disorientation, which contributed to the loss of control. The aircraft experienced overload failure and separation in flight, leading to an in-flight structural failure. Environmental factors such as rain, turbulence, and thunderstorm activity were present and contributed to the event.
Probable Cause
The official probable cause of the accident was loss of control and uncontrolled descent after the pilot continued VFR flight into adverse weather conditions. Contributing factors included the pilot's spatial disorientation, overload failure, rain, turbulence and thunderstorm activity, separation in flight, and in-flight structural failure.