Beech V35 N7947M accident near Bristol, Ohio

Probable cause

The loss of control during cruise flight in instrument conditions due to spatial disorientation.

NTSB analysis

The accident occurred while the airplane was operating in instrument meteorological conditions on an instrument flight plan. While enroute, the pilot had requested a higher cruise altitude on two separate occasions in an attempt to climb above the cloud tops. The final assigned cruise altitude was 9,000 feet. Infrared satellite imagery indicated that the cloud tops were in excess of 9,700 feet near the accident site. Radar track data showed the airplane level at 9,000 feet when it made a 35-degree right turn off the intended route of flight to an east-northeast course. About 60 seconds later, the airplane made a left turn to a north heading followed by a right spiraling descent. During the final 40 seconds of radar data, the airplane descended from 9,100 to 7,800 feet. The calculated descent rate incrementally increased to approximately 4,200 feet per minute. The increasing spiral course and rapid rate of descent was consistent with a pilot experiencing spatial disorientation. According to air traffic control data, the pilot made no distress call and did not indicate if the airplane had experienced any mechanical difficulties. The pilot also did not report any accumulation of structural ice, although there was a high potential for icing conditions at the cruise altitudes used during the accident flight. The distribution of the wreckage was consistent with an in-flight breakup at low altitude. The on-scene investigation revealed no pre-impact mechanical malfunctions or anomalies that would have prevented the normal operation of the airplane or its systems.

Text from the NTSB. Open the NTSB docket for CHI08FA133 for the full record.