Flight History
The airplane departed and intercepted airway V-2, climbing normally to 8,300 feet (assigned 9,000 feet) while tracking approximately 110° magnetic. Radar data showed the airplane at 128 knots indicated airspeed when it abruptly turned left 30° and then appeared to recover. Voice communication during this event was normal with no change in the pilot's level of anxiety. Immediately thereafter, the heading changed more than 90° to the left (northbound), and a maximum rate of descent of 6,750 feet per minute developed before the heading stabilized and the descent slowed.
Impact and Wreckage
The airplane's ground impact site was approximately 1 nautical mile southwest of the last radar target. Wreckage distribution was roughly parallel to V-2. The airplane impacted the mountainside in a steep nose-low, left-wing-down attitude. The left propeller indicated low power on impact. There was no evidence of significant icing or turbulence.
Investigation
The engines, propellers, and governors were disassembled and inspected with no evidence of mechanical malfunction. The pilot, the sole occupant on board, was killed.
Probable Cause
The exact cause of the accident could not be determined.