Crj-200 flight crew reported landing successfully after experiencing a flight control malfunction.

Attributes
ACN	1533764
Time
Date	201804
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Regional Jet 200 ER/LR (CRJ200)
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Aeroplane Flight Control
Person 1
Function	Pilot Not Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Events
Anomaly	Aircraft Equipment Problem Critical Inflight Event / Encounter Loss Of Aircraft Control

Narrative:

While in cruise at FL330 we experienced uncommanded yaw inputs cycling back and forth. We contacted maintenance and started down to FL270 to see if that would resolve the issue. Level at FL270 the issue was still present and we disconnected the autopilot. The motion was still present so I took the controls and we complied with [the] QRH. This guided us to disconnect the yaw damper and; if controllability was a concern; to execute a flaps 20 landing. Because we were empty and had a low reference speed we opted to execute a flaps 20 landing just to play it safe. Because we were experiencing a flight control malfunction we also made the decision to [advise ATC]. We were cleared direct to the airport and landed safely.

Original NASA ASRS Text

Title: CRJ-200 flight crew reported landing successfully after experiencing a flight control malfunction.

Narrative: While in cruise at FL330 we experienced uncommanded yaw inputs cycling back and forth. We contacted Maintenance and started down to FL270 to see if that would resolve the issue. Level at FL270 the issue was still present and we disconnected the autopilot. The motion was still present so I took the controls and we complied with [the] QRH. This guided us to disconnect the yaw damper and; if controllability was a concern; to execute a flaps 20 landing. Because we were empty and had a low reference speed we opted to execute a flaps 20 landing just to play it safe. Because we were experiencing a flight control malfunction we also made the decision to [advise ATC]. We were cleared direct to the airport and landed safely.

Data retrieved from NASA's ASRS site 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.