What happened
Following landing and refueling at a self-service station, the CessNA 320 was taxied to the far end of the displaced threshold on runway 9, which is a published 3,000-foot turf runway. Witnesses noted that the engines sounded normal during the takeoff roll. During the initial climb, the aircraft veered approximately 100 feet north of the runway centerline. The aircraft then struck a telephone pole, and the vertical stabilizer collided with telephone cables at an estimated height of 25 feet above the ground.
The aircraft came to a stop on the ground in a flat attitude, which immediately resulted in a fire. All occupants were able to exit the aircraft, though two required assistance. One passenger later died from second and third-degree thermal burns. The pilot reported that during takeoff, the aircraft lifted and climbed but then stopped gaining altitude and began sinking. He noted that he elected to retract the landing gear to clean up the aircraft configuration. The pilot also stated he was unaware of the exact fuel amounts or which tanks had been fueled by the passenger.
The investigation
A wreckage examination was performed by representatives from the Cessna Aircraft Company and Teledyne Continental Motors (TCM) with FAA oversight. Examination of both engines showed no abnormalities that would have prevented normal operation or the production of rated power. While the left engine's magneto harness assembly sustained fire damage and required replacement, an operational bench test showed no discrepancies. Due to thermal damage, an operational bench test of the right engine's magnetos could not be performed, though no other discrepancies were found.
Flight controls and fuel systems not destroyed by the fire were examined; the landing gear was in the retracted position, flaps were at 10 degrees, and trim settings were near neutral. The left and right fuel valve selectors were both in their respective main tank positions, and fuel samples showed no water contamination. The investigation also noted that the aircraft's weight and balance sheet indicated a useful load of 1,394 lb, with vortex generators on the vertical stabilizer increasing that capacity by 300 lb. The pilot estimated the combined weight of occupants, fuel, and effects to be 1,803 lb.
Findings
- The 1967 Cessna 320 Owner's Manual lacks performance adjustment data for takeoff distances on sod runways, tailwind components, or operations exceeding maximum gross weight.