What happened
The aircraft was in cruise flight at approximately 7,000 feet mean sea level. At 10:32:27, air traffic control instructed the pilot to descend from 7,000 feet to 3,000 feet mean sea level, an instruction which the pilot acknowledged. The final radar contact with the aircraft occurred at 10:32:53, at an altitude of approximately 6,500 feet.
No distress calls were made, and the pilot did not report any mechanical difficulties. Witnesses observed the aircraft within cloud cover for approximately one minute, noting that the engine noise became increasingly loud. As the aircraft emerged from the clouds, it was in a rapid spin with a 45-degree nose-down attitude. Observers noted that the aircraft appeared to be missing part of one wing. The aircraft then nosed straight down and impacted the ground in a steep, nose-down attitude. There were no survivors.
The investigation
An inspection of the left wing revealed fracture surfaces consistent with an overstress fracture. Beyond this structural failure, the inspection of the aircraft revealed no deficiencies that would have prevented normal operation. Weather radar analysis showed a narrow line of echoes near the accident site, with cumulus clouds present and cumulonimbus clouds located to the west and southwest. The radar spectrum width indicated an area of wind shear between 12 to 24 knots along the flight track, signifying significant wind velocities and turbulence.