Flight Details
The pilot was conducting a short cross-country flight, which was his third solo flight in a high-performance single-engine airplane. After departure, the airplane climbed to 20,000 ft mean sea level (msl) before beginning a descent.
ATC Communications
About 8 minutes before the accident, the airplane was southbound, descending to 11,000 ft, and the pilot established communications with air traffic control (ATC). Approximately 4 minutes later, the controller cleared the pilot to descend to 10,000 ft msl and proceed direct to his destination; the pilot acknowledged the clearance. While descending through 13,000 ft msl, the airplane entered a descending left turn. The controller observed the turn and asked the pilot if everything was alright; there was no response. Further attempts to contact the pilot were unsuccessful.
Descent and Impact
Following the descending left turn, the airplane entered a high-speed, nose-down descent toward terrain. The airplane impacted two powerlines, trees, and the terrain in a shallow descent with a slightly left-wing low attitude. Examination of the accident site revealed a long debris field consistent with an impact at high speed and a relatively shallow flightpath angle. All major components were located within the debris field.
Witness Observation
A witness observed the airplane at a high altitude in a steep nose-down descent. The witness noted no signs of distress, such as smoke, fire, or parts separating from the airplane, and heard the engine operating at full throttle.
Postaccident Examination
Examination of the airframe and engine revealed no preimpact mechanical malfunctions or failures that would have precluded normal operation. A performance study indicated that during the left roll and dive, the airplane exceeded the airspeed, load factor, and bank angle limitations published in the Pilot’s Operating Handbook (POH).
Pilot Behavior and Toxicology
An important but unknown factor during the maneuvers was the behavior of the pilot and his activity on the flight controls during the initial roll and dive. The pilot responded normally to ATC communications only 98 seconds before the left roll started. It is difficult to reconcile an alert and attentive pilot with the subsequent roll and descent, but insufficient information exists to determine whether the pilot was incapacitated or distracted during any part of the maneuver. Toxicological specimens contained ethanol at very low levels, below the allowable limit for flight (0.04 gm/dl). While ingestion was possible, the ethanol could have originated from postmortem production; in either case, the levels were too low to cause incapacitation. Minimal available autopsy evidence did not support a determination of incapacitation.
Probable Cause
The official probable cause is the pilot’s failure to arrest the airplane’s left roll and rapid descent for reasons that could not be determined based on the available evidence.