Accident Summary
A fatal accident occurred when an aircraft, en route from Palm Springs, California, to Olathe, Kansas, crashed in an open field. The pilot and his wife were the only occupants and were killed. The aircraft had made a fuel stop at Farmington, New Mexico, before continuing its journey.
Flight History
After departing from Farmington, the aircraft was cleared to flight level 210 (FL210). At 1934, the pilot reported to Denver Air Route Traffic Control Center (ARTCC) that there was some snow but he was "mostly in and out of the tops" and that it was "moderately rough from time to time." The aircraft maintained an easterly heading.
At 2045, Kansas City ARTCC advised the pilot that he was at FL213, and the pilot acknowledged that he had drifted off altitude and was correcting, stating his heading as 060 degrees. Two minutes later, at 2047, the controller informed the pilot that he was at FL203. The pilot responded, "we've had a gyro failure." Shortly after, at 2049, radar contact was lost.
Impact and Investigation
The aircraft struck an open field in a near-vertical attitude. Investigators found no evidence of pre-impact failure of the airframe, engine, propeller, or flight controls. Only one vacuum pump was recovered, and the instrument panel and autopilot system were destroyed. The investigation could not determine a specific reason for the loss of control, but noted that the flight was conducted at night in cloudy conditions.
Probable Cause
The official probable cause was listed as two occurrences: first, a loss of control in flight during normal cruise, with findings of undetermined reason, cloudy weather, dark night light conditions, and spatial disorientation by the pilot-in-command; second, an uncontrolled descent resulting in an in-flight collision with terrain.