Overview
A VFR flight conducted by a noninstrument rated pilot ended with the aircraft entering a left descending spiral and disappearing from radar near the accident site. The aircraft was en route on a northeasterly course, but during the last eight minutes, radar data showed it descending from 14,500 to 13,000 feet on a southwesterly course before the spiral.
Flight Path
Initially, the aircraft was on a northeasterly course. In the final eight minutes, it descended from 14,500 feet to 13,000 feet while tracking southwesterly. The aircraft then abruptly entered a left descending spiral and was lost from radar near the accident site.
Weather Conditions
Meteorological data and pilot reports indicated cloud tops in the area near 15,000 feet, with higher tops further east. Rime icing was probable within clouds.
Preflight Briefing
The pilot received a weather briefing from flight service the evening before the flight, approximately 11 hours prior to departure. The briefing forecast VFR conditions along the route. The pilot did not obtain any further briefing before departing the following morning. Updated weather information, available in the morning, contained reports of poorer conditions than initially forecast.