Accident Sequence
During arrival, the pilot informed Air Route Traffic Control Center (ARTCC) that the destination airport appeared to be covered with fog. She subsequently canceled her IFR flight plan. Ground witnesses reported that the aircraft made several passes over the airport. They noted that horizontal visibility was nil, though blue sky was visible directly above. On the last pass, the aircraft crossed the approach end of the runway with landing gear and flaps extended, angling to the left of the runway heading. Moments later, witnesses heard the engines increase to full power, followed by silence. The aircraft was found where it impacted rising snow-covered terrain approximately 1/8 mile south of the midpoint of the airport. Evidence indicated the aircraft was in a steep descending, right-wing-low attitude at impact. No preimpact part failure or malfunction was found.
Injuries and Damage
One passenger sustained serious injuries, and five other occupants were killed.
Investigation Findings
The investigation identified three occurrences. Occurrence #1: an in-flight encounter with weather during the approach in VFR pattern final approach. Contributing factors included improper in-flight planning/decision by the pilot, snow-covered terrain, fog, continued VFR flight into instrument meteorological conditions (IMC), and the pilot's visual/aural perception. Occurrence #2: loss of control during a go-around (VFR). The go-around was initiated, but the pilot did not maintain aircraft handling. Occurrence #3: an in-flight collision with terrain/water during approach. The terrain was rising, and the descent was uncontrolled.
Probable Cause
The official probable cause is a combination of the pilot's improper in-flight planning/decision, continued VFR flight into IMC, and failure to maintain aircraft control during a go-around, resulting in an uncontrolled descent into rising snow-covered terrain.