Narrative:

After a normal touchdown and deployment of idle thrust reverse; I had a difficult time maintaining directional control of aircraft after nosewheel touchdown. Even with differential brake application and rudder input aircraft continued to pull left and eventually exited the runway into the mud. When it stopped I initiated an emergency evacuation through the cabin door only. Airport crash fire rescue equipment met the aircraft shortly thereafter. The touchdown seemed normal with just a little bit of main wheel shimmy. Thrust reverse effect could be felt as soon as they deployed. When the nose initially touched it seemed to roll straight; but just before I began to apply brakes the airplane pulled left. I pushed on right rudder; and tried to push the right brake harder but it seemed to have less and less effect on the direction of the aircraft as it slowed. It did not seem like a asymmetric braking event. Two things I distinctly remember about the landing: at touchdown or shortly after several things fell off of my flight kit onto the side console--my notebook; the plastic sunshade; and one approach plate binder. I heard the sunshade fall and felt it hit my left arm but did not think anymore about it. The other thing that struck me as odd is as the aircraft was nearly to exit the runway I reached for the tiller; but for some reason could not immediately grab it. After we deplaned I eventually found the sunshade beside the left rudder pedal. The approach plate binder ended up on top of my other one on the side console (but was still behind the tiller); and the notebook on the floor beside my seat. It happened so fast I don't really know what it was. It was just a feeling of 'why can't I turn right?' all of a sudden. If I knew why it happened exactly; I would better know how to prevent a recurrence. If it turns out to be the sunshade; I would make sure it's attached to something before flying. Outside of that I don't know.

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Original NASA ASRS Text

Title: A CRJ700 flight crew lost control of the aircraft on landing roll and exited the runway. Passengers evacuated safely out the cabin door.

Narrative: After a normal touchdown and deployment of idle thrust reverse; I had a difficult time maintaining directional control of aircraft after nosewheel touchdown. Even with differential brake application and rudder input aircraft continued to pull left and eventually exited the runway into the mud. When it stopped I initiated an emergency evacuation through the cabin door only. Airport CFR met the aircraft shortly thereafter. The touchdown seemed normal with just a little bit of main wheel shimmy. Thrust reverse effect could be felt as soon as they deployed. When the nose initially touched it seemed to roll straight; but just before I began to apply brakes the airplane pulled left. I pushed on right rudder; and tried to push the right brake harder but it seemed to have less and less effect on the direction of the aircraft as it slowed. It did not seem like a asymmetric braking event. Two things I distinctly remember about the landing: At touchdown or shortly after several things fell off of my flight kit onto the side console--my notebook; the plastic sunshade; and one approach plate binder. I heard the sunshade fall and felt it hit my left arm but did not think anymore about it. The other thing that struck me as odd is as the aircraft was nearly to exit the runway I reached for the tiller; but for some reason could not immediately grab it. After we deplaned I eventually found the sunshade beside the left rudder pedal. The approach plate binder ended up on top of my other one on the side console (but was still behind the tiller); and the notebook on the floor beside my seat. It happened so fast I don't really know what it was. It was just a feeling of 'why can't I turn right?' all of a sudden. If I knew why it happened exactly; I would better know how to prevent a recurrence. If it turns out to be the sunshade; I would make sure it's attached to something before flying. Outside of that I don't know.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.