Narrative:

We encountered a runaway rudder trim to a full right deflection in approximately 5-6 seconds at altitude. After regaining airplane control and landing without further events; maintenance control had called local maintenance and instructed them to ops check the trim switch and subsequently defer the autopilot based solely on our write up. Our write up was 'climbing from 210-220 the rudder trim traveled full right. Both yaw dampers disconnected. Disconnected autopilot and regained airplane control; reengaged yaw dampers; complied with QRH and landed uneventfully.' local maintenance operations checked the switch; deferred the autopilot; cat ii; and rvsm and said we're now good to go. We then refused the aircraft based on their 'fix' as the autopilot has no correlation to the rudder trim. The auto trim function is strictly related to pitch servos; not rudder trim and the only way; according to the aircraft flight manual (afm) for the trim to move is the switch. There was significant communication and some misunderstandings between the captain and maintenance pertaining to whether or not mechanics were being sent on a road trip. End result was indeed a road trip and changing the rudder trim panel as a wire had become frayed. In speaking with another safety rep last week about another issue on another aircraft; it seems that we have a serious problem with maintenance 'knee-jerking' a deferral solution to a problem without fully researching what the actually issue is. The aircraft rolled to approximately 25-30 degrees of bank to the right with the brick fully deflected the other way. Maintenance control deferred the autopilot which has no correlation to the rudder trim. This was absolutely unacceptable. Maintenance control led the crew down a path that we; the crew threw the bs flag on. We took a minute to sit back; evaluate systems; reconsult the afm and ensure what we thought was correct. The company must preach to maintenance what the training guys preach to the pilots. When you have a situation in the airplane; wind your watch; sit back; survey the situation; and then work in the appropriate solution. The company has this culture and insensitivities all parties with financial rewards. I'm quite certain the maintenance controller knows the autopilot has nothing to do with rudder trim. Furthermore; the maintenance controller said 'based on how we wrote it up; that's what we're going to do' that's clearly unacceptable. What if the landing lights were on at the time? Are we going to defer these too?

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Original NASA ASRS Text

Title: CRJ200 First Officer reports a runaway rudder trim climbing to FL220. The aircraft rolls 25 degrees to the right before control is regained and the trim is centered. The flight continues to destination landing uneventfully. Maintenance attempts to blame the autopilot and defers it. The crew realizes that the autopilot has no inputs to the rudder trim and refuses the aircraft. Later Maintenance discovers frayed rudder trim wiring which caused the anomaly.

Narrative: We encountered a runaway rudder trim to a full right deflection in approximately 5-6 seconds at altitude. After regaining airplane control and landing without further events; Maintenance Control had called Local Maintenance and instructed them to ops check the trim switch and subsequently defer the autopilot based solely on our write up. Our write up was 'Climbing from 210-220 the rudder trim traveled full right. Both yaw dampers disconnected. Disconnected autopilot and regained airplane control; reengaged yaw dampers; complied with QRH and landed uneventfully.' Local Maintenance Operations checked the switch; deferred the autopilot; Cat II; and RVSM and said we're now good to go. We then refused the aircraft based on their 'fix' as the autopilot has no correlation to the rudder trim. The auto trim function is strictly related to pitch servos; not rudder trim and the only way; according to the Aircraft Flight Manual (AFM) for the trim to move is the switch. There was significant communication and some misunderstandings between the Captain and Maintenance pertaining to whether or not mechanics were being sent on a road trip. End result was indeed a road trip and changing the rudder trim panel as a wire had become frayed. In speaking with another safety rep last week about another issue on another aircraft; it seems that we have a serious problem with Maintenance 'knee-jerking' a deferral solution to a problem without fully researching what the actually issue is. The aircraft rolled to approximately 25-30 degrees of bank to the right with the brick fully deflected the other way. Maintenance Control deferred the autopilot which has NO CORRELATION to the rudder trim. This was absolutely unacceptable. Maintenance Control led the crew down a path that we; the crew threw the BS flag on. We took a minute to sit back; evaluate systems; reconsult the AFM and ensure what we thought was correct. The company must preach to Maintenance what the training guys preach to the pilots. When you have a situation in the airplane; wind your watch; sit back; survey the situation; and then work in the appropriate solution. The company has this culture and insensitivities all parties with financial rewards. I'm quite certain the Maintenance Controller knows the autopilot has nothing to do with rudder trim. Furthermore; the Maintenance Controller said 'based on how we wrote it up; that's what we're going to do' That's clearly unacceptable. What if the landing lights were on at the time? Are we going to defer these too?

Data retrieved from NASA's ASRS site as of July 2013 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.