Background
The accident flight was conducted by an ATP-rated pilot with a passenger on board. The purpose of the flight was to pick up a patient for transport to a VA hospital. The destination airport was uncontrolled and operated under visual flight rules (VFR) only.
Accident Sequence
During the flight, the pilot canceled an instrument flight rules (IFR) clearance with air traffic control and reported the airport in sight. The airport was reporting VFR conditions, but rising, mountainous terrain existed to the northeast. Local authorities reported that the top third of the mountain was obscured in clouds during the morning of the accident. After canceling IFR, no subsequent radio calls were received from the flight, and the flight did not arrive at its destination.
Wreckage Examination
The wreckage was found several hours later near the crest of Holston Mountain, half a mile east of the Holston Mountain VOR. An examination of the wreckage indicated the aircraft impacted upsloping, wooded terrain while at a climb angle of 8 degrees. Disintegration of the wreckage was indicative of a high-speed impact. No evidence of mechanical malfunction or failure was found during the examination.
Probable Cause
The official probable cause stated that the pilot attempted VFR flight into instrument meteorological conditions (IMC) and failed to maintain a proper altitude over mountainous terrain. A contributing factor was the clouds and obscuration at the accident site.