What happened
During the landing phase on runway 04, an aircraft impacted a four-foot high snow bank located alongside the runway. The pilot reported that the aircraft was properly aligned with the runway centerline at the start of the landing roll. However, immediately upon touchdown, the aircraft began veering to the left. In an attempt to maintain the centerline, the pilot applied right rudder to correct the swerve, but the aircraft continued its leftward trajectory. The plane eventually struck the snow bank and came to a rest in a nearby ditch.
The investigation
The runway surface at the time of the accident was described by the airport manager as being covered with a 1/2 inch layer of dry snow over a 1/16 inch layer of ice. Tire tracks observed on the runway indicated that the aircraft traveled straight along the runway for approximately 200 feet before entering a sweeping left curve.
Prior to takeoff, the pilot noted that the left main wheel had crossed an area containing snow ridges several inches in height. The pilot also stated that full brake pressure was not applied during the pre-takeoff procedures. A post-accident examination of the braking system was conducted; investigators found no discrepancies with either brake caliper and detected no water or foreign objects within the brake lines. The inspection confirmed that the left brake functioned according to its design specifications.
Findings
- The runway surface consisted of ice covered by a layer of dry snow.
- The aircraft maintained the centerline for approximately 200 feet after touchdown before deviating.
- The left main wheel had previously encountered uneven snow ridges during the takeoff roll.