Narrative:

During taxi-out; first officer was performing flight control (aileron) check and discovered that control yoke was binding. When yoke was displaced left or right and released; yoke would not return to center but would stop at 2-3 units from center. Once stopped; there was significant resistance to moving the yoke to center. First officer asked for my opinion and I concurred with his observations. We returned to the gate. Once on the gate we discovered a similar write-up approximately one week earlier. Maintenance came on board to check and discovered that the trim motor could only move the wheel 2-3 units left or right before binding overpowered the aileron trim motor and yoke stopped moving. Aircraft was taken out of service.

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Original NASA ASRS Text

Title: A B767-300ER Captain reported abnormal aileron check on taxi out. They returned to the gate where the flight was canceled.

Narrative: During taxi-out; First Officer was performing flight control (aileron) check and discovered that control yoke was binding. When yoke was displaced left or right and released; yoke would not return to center but would stop at 2-3 units from center. Once stopped; there was significant resistance to moving the yoke to center. First Officer asked for my opinion and I concurred with his observations. We returned to the gate. Once on the gate we discovered a similar write-up approximately one week earlier. Maintenance came on board to check and discovered that the trim motor could only move the wheel 2-3 units left or right before binding overpowered the aileron trim motor and yoke stopped moving. Aircraft was taken out of service.

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.