Accident Overview
An aircraft operating on a flight from Helena, Montana to Sheridan, Wyoming, impacted terrain south of Fort Smith, Montana. The accident occurred in an area of rising terrain where the aircraft encountered variable low ceilings, snow, and rain. As the flight continued southward, the distance between the mountainous and hilly terrain and the cloud base diminished. The aircraft subsequently struck a gently up-sloping grassy ridge.
Flight History
The aircraft departed Helena, Montana, with Sheridan, Wyoming as its intended destination. During the en route portion of the flight, it entered an area of increasing terrain elevation just south of Fort Smith. At that time, weather conditions included variable low cloud ceilings, snow, and rain.
Accident Sequence
As the aircraft continued its southerly course, the terrain rose and the cloud base lowered, reducing the available clearance. The aircraft ultimately impacted a grassy ridge that sloped gently upward. The impact was with the terrain, and the aircraft came to rest at that location.
Weather Conditions
At the time the aircraft entered the area south of Fort Smith, weather reports indicated variable low ceilings, snow, and rain. These conditions persisted as the aircraft progressed southward, with the cloud base and terrain converging until impact.