What happened
The pilot initiated an instrument flight rules (IFR) flight plan for a journey estimated to last approximately 2 hours and 47 minutes, requesting a cruising altitude of 12,000 ft msl. Although the flight planning software provided weather updates regarding turbulence and convective SIGMETs, it remains unclear if the pilot evaluated these reports. The aircraft departed roughly 45 minutes later than the scheduled time.
Shortly after takeoff, the pilot contacted air traffic control to receive an IFR clearance. The controller instructed the pilot to climb to 10,000 ft msl and issued a weather advisory regarding heavy and moderate precipitation, which the pilot acknowledged. Following a subsequent instruction to climb to 12,000 ft msl, the controller began a position relief briefing with a replacement controller.
During this period, the aircraft began to deviate from its intended southwesterly course. Flight track data indicates that at 9,800 ft msl, the plane entered a 45-second, 270-degree right turn, descending to 8,700 ft msl before leveling out on an easterly track. Shortly after the controller noticed the deviation and queried the pilot, the pilot transmitted that he had "lost" something. This was followed by one final transmission 27 seconds later, which served as the last communication from the aircraft.
The flight path then became erratic, moving east on a wavering track while descending. The aircraft eventually entered a tight, descending right-hand spiral and disappeared from tracking. The aircraft crashed in a heavily wooded region of Trout Creek, resulting in the total destruction of the plane and five fatalities.