What happened
A noncertificated pilot informed the Air Route Traffic Control Center (ARTCC) that he was flying at 11,500 feet MSL. During a series of exchanges concerning weather conditions, the controller inquired if the pilot was flying above an overcast layer and if clearance to descend through the clouds was required. The pilot stated he was "on-top."
When asked if he possessed recent training or experience in Instrument Flight Rules (IFR) operations, the pilot admitted he did not. He informed the controller that he had previously descended through clouds without issue. Despite the controller advising that entering the clouds while flying under Visual Flight Rules (VFR) would be illegal, the pilot stated that a "broken spot" in the clouds allowed for a descent. Shortly after this communication, all contact with the aircraft was lost.
Following the loss of radar contact, an in-flight breakup occurred. Wreckage was distributed over a 1,600-foot area. Radar data indicated several changes in altitude and heading prior to the loss of signal, and witnesses reported variations in engine sound before the impact.
The investigation
An examination of the wreckage revealed that the stabilator and portions of the left wing had separated from the aircraft due to overload failure.
Toxicology testing was performed on the pilot. Analysis of the pilot's blood detected a trace amount of cocaine (less than 0.020 mcg/ml) and 0.129 mcg/ml of Benzoylecgonine, a metabolite of cocaine. Additionally, testing of liver fluid showed 0.051 mcg/ml of Benzoylecgonine.