Incident
A pilot reported that during a landing, when the nose wheel touched down, a severe vibration began and the aircraft veered to the left. The pilot stated that she pulled the yoke aft, but this had no effect. She also applied brakes but could not stop the aircraft or make it turn right. Subsequently, the aircraft drifted into a snow bank beside the runway and nosed over.
Witness Observation
A witness observed that the left main landing gear caught the snow on the side of the runway for approximately 30 feet, and then the aircraft turned into the snow.
Examination
An examination of the nose landing gear was conducted, but no mechanical problems were found.