Accident Sequence
At approximately 0250 EDT, a pilot conducting a positioning flight collided with trees and terrain during a VOR approach. The pilot had departed at 0217 EDT after two previous flights and reported feeling fatigued. About five minutes before starting the approach, she turned off the aircraft heater. While being vectored, she twice misread back the direction of turn but was otherwise accurate and responsive. The pilot stated she fell asleep after lowering the landing gear. A post-crash fire erupted, but the pilot exited the aircraft with injuries considered minor.
Pilot Fatigue
The pilot reported being awake about 20 hours at the time of the accident. She had contemplated staying overnight due to fatigue but continued the flight. She used the heater on the ground and during takeoff. En route, she felt fatigued and considered returning but proceeded.
Heater Inspection
Pressure testing of the heater after the accident revealed leaks at a gasket and screw (where the fuel nozzle was mounted) and at two of three cross-over tubes. However, investigators attributed these leaks to impact damage. No evidence of preimpact heater failure or malfunction that would have allowed carbon monoxide to enter the cockpit was found. Two pilots had used the heater on previous flights without noticing problems or symptoms of carbon monoxide poisoning.
Weather and Approach
Weather at a station about 18 miles west at 0255 EDT reported a broken ceiling at 300 feet. The minimum descent altitude (MDA) for the approach was 352 feet AGL (440 feet MSL). The pilot had requested a VOR approach.