Flight Planning and Briefing
Prior to departure on the first leg of a night cross-country cargo flight, the pilot obtained a weather briefing. The briefing included an AIRMET that warned mountains could be obscured by clouds and that precipitation, mist, and fog might be encountered along the route. The pilot filed a VFR flight plan with a planned cruise altitude of 6,500 feet. The flight departed at 1950 Pacific standard time.
Radar Data
Radar data tracked the flight's progress. At 2036:09, the airplane was 20 nautical miles north of the accident site, proceeding south at an altitude of 6,400 feet. At 2046:17, it was 1.16 nautical miles from the accident site, continuing south at 6,300 feet. Between 2046:17 and 2046:53—the time of the last encoded altitude—the airplane descended from 6,300 feet to 5,500 feet while maintaining a southerly heading. Radar contact was lost at 2048.
Accident Site and Conditions
The airplane impacted trees in mountainous terrain at an elevation of 5,099 feet. Search and rescue personnel reached the accident site 5 hours after the accident. They reported hard blowing snow, winds from the west at 30 miles per hour, and 3 to 4 feet of fresh snow covering the area. A local volunteer residing 12 miles south of the accident site at an elevation of 1,678 feet reported that between 2100 and 2200 on the evening of the accident, there was light rain falling and the temperature was 34 degrees Fahrenheit.
Aircraft Examination
A post-accident examination of the airplane revealed no evidence of any mechanical anomalies that would have prevented normal operation.