Narrative:

I aborted our takeoff at approximately 50 KTS due to excessive nosewheel vibration and notified ATC that we were doing so. The airplane was brought to a slow roll and we exited on a nearby high speed taxi way. Upon exiting onto the taxiway using differential power I noticed the tiller was not responding so I continued to use differential power and braking to maintain the taxiway centerline where I brought the airplane to a slow and controlled stop. We then contacted operations and had a tug tow us back into the gate where the passengers were deplaned. Inspection by maintenance found that the steering arm that connects to the nose wheel was completely sheered off.

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Original NASA ASRS Text

Title: A SAAB 340 Captain rejected the takeoff at about 50 KTS due to excessive vibration and an unresponsive nose wheel steering tiller. Maintenance inspection revealed the steering arm had broken completely free from its actuator.

Narrative: I aborted our takeoff at approximately 50 KTS due to excessive nosewheel vibration and notified ATC that we were doing so. The airplane was brought to a slow roll and we exited on a nearby high speed taxi way. Upon exiting onto the taxiway using differential power I noticed the tiller was not responding so I continued to use differential power and braking to maintain the taxiway centerline where I brought the airplane to a slow and controlled stop. We then contacted Operations and had a tug tow us back into the gate where the passengers were deplaned. Inspection by Maintenance found that the steering arm that connects to the nose wheel was completely sheered off.

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.