What happened
During a flight through instrument meteorological conditions, an aircraft experienced a catastrophic loss of control. Prior to departure, the pilot had received a weather briefing from the AFSS that detailed hazardous conditions along the intended route, including snow, turbulence, icing, and freezing rain. Although the pilot filed a flight plan for a cruise altitude of 28,000 feet, the aircraft was observed at 27,000 feet during the final stages of the flight.
Approximately 32 minutes into the flight, the pilot reported experiencing issues with the attitude gyro and noted that the aircraft was being hand-flown. Shortly thereafter, the pilot declared an emergency, though briefly retracted the declaration when the instrument appeared to function again. The pilot then expressed a need to descend to find visual conditions. Radar tracking showed the aircraft performing a series of steep climbs and descents over a four-and-a-half-minute period. A nearby commercial pilot reported hearing the pilot indicate the aircraft was in a spin. The aircraft eventually impacted the ground in a steep, nose-down attitude, leading to a post-impact fire that destroyed the plane. There were 0 survivors.
Findings
Investigations into the accident revealed that the engines, flight controls, and flight instruments showed no evidence of pre-existing mechanical anomalies. However, a witness noted that the pilot had mentioned problems with the attitude gyro two days before the accident, and there was no documentation showing that the component had been inspected. Additionally, while the pilot frequently utilized autopilot during flight, there was no record of the pilot hand-flying the aircraft in instrument conditions prior to this event. The malfunctioning attitude gyro is a primary factor in the sequence of events leading to the loss of control.