What happened
The pilot, who held a recent instrument rating, received a weather briefing from the Cedar City (CDC) Flight Service Station before filing an instrument flight rules (IFR) flight plan from Provo (PVU) to St. George (SGU). Although current weather for St. George was unavailable, the briefing included conditions for Cedar City, located approximately 45 miles north-northeast of the destination. The pilot was advised of moist, unstable air, rain, obscured mountains, and cumulus clouds along the route. Additionally, a pilot report indicated encounters with clear icing near Cedar City at 13,000 feet.
As the aircraft approached Milford at 11,000 feet, the pilot contacted Cedar City FSS for an update. St. George weather remained unavailable, but thunderstorms were reported en route. The pilot switched to Air Route Traffic Control Center frequency and received clearance to descend to 10,000 feet, then climb to 12,000 feet. Shortly thereafter, radio and radar contact were lost. Witnesses observed an aircraft flying into a weather cell, followed by an explosive noise and parts of the aircraft falling from the cloud. Pea-sized hail subsequently fell from the clouds.
The investigation
The wreckage was scattered over an area measuring 1-1/4 miles. Examination revealed that the wings and stabilizers separated in flight. Investigators found no evidence of pre-accident cracks or fatigue in the aircraft structure.