Regional Jet 700 ER/LR (CRJ700)
Flight Crew Air Transport Pilot (ATP)
Confusion; Distraction; Troubleshooting; Training / Qualification
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance
Aircraft Equipment Problem Dissipated; Flight Crew FLC complied w / Automation / Advisory; General Release Refused / Aircraft Not Accepted; General Maintenance Action
Aircraft
At FL350; straight and level cruise with autopilot engaged. Aircraft began a roll to the right. Crew noticed rudder brick off center. Scanned instruments and noted rudder trim full nose left. Pilot flying (First Officer) disconnected autopilot and overrode runaway. Pilot not flying (Captain) re-centered rudder trim per QRH and re-engaged autopilot. After landing; Contract Maintenance did a check of the AFCS fault codes (none noted) and an operational test of the rudder trim system. After checks complete; aircraft signed off OK for service. I exercised Captain's authority and refused to fly the aircraft since there was no indication of why it happened and no guarantees that it would not happen again.
[Narrative 2 contained no additional information.]
A CRJ-700 rudder trim deflected full left with the autopilot engaged; so the QRH was completed; the rudder re-centered and the flight continued but the Captain refused the aircraft for further service after Maintenance found no faults.