What happened
The pilot reported conducting a normal approach followed by touchdown and initial roll-out. During this phase, the aircraft veered to the right and struck a snowbank measuring three to four feet in height.
The investigation
An examination of conditions revealed that snow had been falling for more than 12 hours prior to the incident. Although an 80-foot-wide path had been plowed down the center of the runway, three inches of snow remained within this cleared area. No ice was directly reported on the surface at the time of landing, but braking action was assessed as nil.
Findings
The pilot noted that a previous ice storm had deposited between one-quarter and one-half inch of ice on the runway before the snowfall began. Evidence of this earlier icing condition was present earlier in the day when a Boeing 737 slid off a taxiway. The pilot stated that knowledge of the prior ice conditions would have prevented the landing attempt.
Safety message
Pilots must carefully evaluate historical weather data and recent incident reports, such as aircraft sliding on taxiways, which may indicate residual ice hazards even after snow removal operations.