What happened
A medical transport flight, operating under instrument flight rules (IFR) during night instrument meteorological conditions (IMC), crashed in a snow-covered region approximately 32 km southeast of Reno-Tahoe Airport. The flight was carrying a pilot, two medical crew members, and two passengers.
Flight tracking data and onboard instrumentation indicated that shortly after takeoff, the autopilot system experienced a period of disengagement and subsequent reengagement. While the aircraft initially followed the prescribed departure procedure, approximately 11 minutes into the flight, the plane executed a 90-degree right turn, deviating from the intended waypoint. During this period, the autopilot disengaged a second time and remained inactive for the rest of the flight.
During this phase, the aircraft's climb rate leveled off at roughly 18,300 ft msl, failing to reach the cleared altitude of 25,000 ft msl. After a brief period of level flight, the aircraft turned to a northeasterly heading and reached an altitude of 19,400 ft msl before entering a descending right turn. The rate of descent accelerated sharply from 1,800 fpm to approximately 13,000 fpm. ADS-B tracking was lost at an altitude of about 11,100 ft msl near the crash site. The impact resulted in the total destruction of the aircraft and five fatalities.
Findings
Data analysis shows that the autopilot disengaged and was not reengaged following a significant deviation from the departure procedure, coinciding with a period of unstable flight and an extreme increase in the rate of descent.