MITSUBISHI CL-600-2B19SKYWEST AIRLINES INC

The airplane’s right turn, which developed during the landing rollout and persisted until the airplane came to rest, for reasons that could not be determined based on the available evidence. Contributing to the incident was the pilot’s reliance primarily on differential braking, rather than sufficient and sustained opposing rudder pedal, when attempting to arrest the turn.

The uncommanded left deflection of the airplane's nosewheel for reasons that could not be determined because postincident examination of the nosewheel steering system did not reveal any anomalies that would have precluded normal operation.

The flight crew’s inability to maintain the airplane on the runway centerline after touchdown due to the reduced braking action resulting from the deteriorating weather conditions, which caused the airplane’s departure from the runway surface. Contributing to the accident were the delay in performing the runway assessment for undetermined reasons and failure to close the runway. Also contributing to the accident was the controller’s failure to advise the accident flight crew that braking action was no longer cons…

The captain’s excessive left rudder pedal input during the takeoff ground roll, which caused a large heading deviation and a left roll upon rotation that resulted in the left wingtip striking the ground.  

the captain's inability to maintain directional control of the airplane due to his application of excessive reverse thrust, which degraded the effectiveness of the rudder in controlling the airplane's heading. Contributing to the accident were the captain's (1) situational stress resulting from his concerns about stopping performance and (2) attentional limitations due to the high workload during the landing, which prevented him from immediately recognizing the use of excessive reverse thrust.