What happened
The pilot received a weather briefing prior to departure that included notification of an AIRMET for icing conditions. The airplane departed at 1534.
At 1639, air traffic control established the last contact with the aircraft when the pilot acknowledged a frequency change while maintaining an altitude of 11,000' msl. Approximately one minute after this communication, the airplane dropped off radar.
At the time of the flight, a center weather advisory was in effect, which advised of moderate isolated severe mixed/rime icing in clouds between 4,000' and 13,000'.
The investigation
An inspection of the wreckage indicated that the airplane experienced an inflight breakup. Investigators found no evidence of any pre-accident failures or malfunctions regarding the engines or the airplane.