Incident
The aircraft was in cruise at 15,000 feet MSL when the pilot requested ATC clearance to deviate around a thunderstorm depicted on the onboard Stormscope. After clearing that cell, ATC provided a vector to rejoin the airway. The pilot then requested another deviation to avoid a second thunderstorm cell. Shortly thereafter, radio communication and radar contact were lost.
Investigation
Investigators determined that the accident exhibited characteristics consistent with an inflight breakup at low altitude, caused by pilot-induced overload. A study of meteorological and radar data showed that the aircraft had penetrated the core of a thunderstorm of at least moderate intensity.
Findings
The breakup was attributed to structural overload resulting from pilot actions during the thunderstorm encounter. No other contributing factors were identified.