What happened
While executing an instrument approach toward its destination airport, a business jet passed the initial approach fix and subsequently lost all radio and radar communication. During this period, multiple witnesses provided accounts of the aircraft's final moments. One observer noted hearing irregular engine sounds and observed the aircraft performing a left-hand descending turn. This witness further reported hearing an explosion and seeing a large plume of smoke rising from behind a nearby ridge.
Another witness observed a small white twin-engine aircraft performing a left turn with the nose pitched toward the ground, appearing as though it were attempting to land on a roadway. A third individual reported hearing the continuous roar of the engines throughout a vertical nose-dive that ended in a ground impact. There were no survivors of the crash.
Findings
Post-accident inspections of the engines and the airframe revealed no mechanical failures or structural defects that would have hindered the aircraft's ability to fly normally. However, at the time of the accident, the National Weather Service had issued a SIGMET for mountain wave activity and severe turbulence. Satellite imagery confirmed the presence of rotor clouds and altocumulus undulates directly over the crash site, indicating severe atmospheric instability.