Flight Details
The pilot of a general aviation aircraft obtained a weather briefing for an instrument flight rules (IFR) flight to Taos, New Mexico. The briefing included forecasts of light to moderate rime icing and moderate turbulence at the destination. The aircraft departed and proceeded toward Taos.
Weather Conditions
During the descent, approximately 30 nautical miles east of the Taos VOR at 15,200 feet, the pilot reported encountering light rime icing. Three minutes later, the pilot reported freezing rain. The freezing level was determined to be about 10,700 feet. The aircraft entered clouds about six nautical miles east of the point where light rime icing was reported and remained in clouds until descending below 10,000 feet. A pilot report (PIREP) indicated severe turbulence on the eastern slope of the mountain range.
Accident Sequence
The aircraft was cleared for the VOR DME-B approach to Taos Airport, and radar services were terminated. The aircraft impacted the ground in a steep nose-down attitude seven nautical miles southeast of the VOR and one nautical mile right of the inbound approach course. Radar data showed cyclic variations in ground speed from 120 to 190 knots as the aircraft crossed the high mountain range east of Taos. All four occupants were killed.
Investigation Findings
The official investigation determined the probable cause to be the pilot's decision to continue flight into known adverse weather conditions and the ensuing inadvertent stall due to airframe ice. Factors in the accident were the weather conditions, including icing and turbulence.