Incident Overview
A non-scheduled domestic cargo positioning flight sustained substantial damage upon impact with a snowbank and terrain during landing. The pilot reported that the approach was conducted under moderate to heavy snowfall at Central Wisconsin Airport. Runway conditions were reported as poor and the runway was snow covered. A crosswind existed and wind shear was noted during the approach.
Approach and Landing
Central Wisconsin Tower advised the pilot of a snow berm remaining on the west side of Runway 35 because the runway was not plowed to its full width. After acquiring visual contact with the runway lights, the pilot judged the runway centerline by aligning the aircraft's position between the lights. Following main wheel touchdown, the nose wheel was lowered. The pilot observed via landing lights that the aircraft was close to the snow berm and gradually applied right rudder pedal to steer away. No braking action was applied to avoid skidding; the airspeed was above 60 knots with ample runway remaining to decelerate.
Loss of Control
As the pilot positioned the power levers into the beta range, the left outer main landing gear tire made contact with the edge of the remaining snow berm. The aircraft began to yaw to the left. Despite applying additional right rudder, the yaw continued. The nose wheel struck the snow berm and broke off, causing the aircraft to sail over the berm. The main landing gear wheels collapsed completely, and the aircraft slid to a stop approximately 200 feet west of Runway 35, off the runway. The aircraft sustained substantial damage.