Accident Summary
A witness observed the aircraft briefly before it struck the ground. The aircraft was seen flying toward a dark cloud at an unknown altitude, appearing too high to fly beneath it. Shortly after, the witness heard the engine noise increase and decrease, then increase until it was loud, followed by a sound resembling an explosion. The crash was not witnessed, but smoke from the impact site was observed.
Witness Observations
Another witness near the crash site reported extremely windy conditions with heavy rain and restricted visibility at the time of the accident. These weather conditions were consistent with the dark cloud noted by the first witness.
Wreckage Examination
Examination of the wreckage revealed that the outboard wing panels had failed due to positive overloads, and the left horizontal stabilizer had failed downward. These separated components were found between three-quarters and one mile from the main wreckage site.
Flight Details
Prior to the flight, a passenger who had paid for fuel and minor maintenance stated that the purpose of the flight was surveying. However, no surveying equipment was found aboard the aircraft. Sheriff personnel indicated that the aircraft was under surveillance for an illegal operation at the time of the accident.
Probable Cause Findings
The official probable cause findings, as determined by the investigation, are as follows:
- Occurrence #1: In-flight encounter with weather during cruise. Findings: The pilot made a poor judgment and lacked proper qualifications. The pilot initiated flight into known adverse weather, specifically a thunderstorm with turbulence. The pilot continued VFR flight into IMC, exhibiting overconfidence in personal ability.
- Occurrence #2: Loss of control in flight during cruise. Findings: The pilot failed to maintain aircraft handling and experienced spatial disorientation due to a lack of total instrument time.
- Occurrence #3: Airframe/component/system failure during uncontrolled descent. Findings: The pilot exceeded the design stress limits of the aircraft, leading to overload and separation of the wing and horizontal stabilizer surfaces.
- Occurrence #4: In-flight collision with terrain during uncontrolled descent.
These findings collectively indicate that the accident resulted from the pilot's decision to fly into adverse weather conditions, subsequent loss of control, and structural failure of the aircraft.