Narrative:

At FL280, we got an autoplt trim left wing down caution message for a couple of seconds, then an autoplt trim right wing down caution message. Briefly then an autoplt trim left wing down message for a couple of seconds. Then another autoplt trim right wing down message persisted. We ran the abnormal checklist. One is to disconnect the autoplt. The first officer who was flying noted the ailerons were extremely stiff and difficult to move. It took excessive pressure on the control inputs to turn the aircraft. The elevator and rudder operated normally. We contacted maintenance. They were unable to determine a cause or a solution while airborne. We decided to divert to iad. We talked to dispatch about the winds at iad (which were calm). The flight attendant was notified of the situation and the passenger were briefed. We landed at iad without incident. The aircraft was flown by hand after the malfunction was discovered. Supplemental information from acn 522142: the first officer landed long as he had aileron flight control problems. I got the more experienced pilot to land in an emergency landing. He was doing fine until he tried to settle the aircraft on smoothly but it floated.

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Original NASA ASRS Text

Title: CL65 FO LANDED LONG DURING AN EMER DIVERSION TO ANOTHER ARPT DUE TO AILERON CTL PROB.

Narrative: AT FL280, WE GOT AN AUTOPLT TRIM L WING DOWN CAUTION MESSAGE FOR A COUPLE OF SECONDS, THEN AN AUTOPLT TRIM R WING DOWN CAUTION MESSAGE. BRIEFLY THEN AN AUTOPLT TRIM L WING DOWN MESSAGE FOR A COUPLE OF SECONDS. THEN ANOTHER AUTOPLT TRIM R WING DOWN MESSAGE PERSISTED. WE RAN THE ABNORMAL CHKLIST. ONE IS TO DISCONNECT THE AUTOPLT. THE FO WHO WAS FLYING NOTED THE AILERONS WERE EXTREMELY STIFF AND DIFFICULT TO MOVE. IT TOOK EXCESSIVE PRESSURE ON THE CTL INPUTS TO TURN THE ACFT. THE ELEVATOR AND RUDDER OPERATED NORMALLY. WE CONTACTED MAINT. THEY WERE UNABLE TO DETERMINE A CAUSE OR A SOLUTION WHILE AIRBORNE. WE DECIDED TO DIVERT TO IAD. WE TALKED TO DISPATCH ABOUT THE WINDS AT IAD (WHICH WERE CALM). THE FLT ATTENDANT WAS NOTIFIED OF THE SIT AND THE PAX WERE BRIEFED. WE LANDED AT IAD WITHOUT INCIDENT. THE ACFT WAS FLOWN BY HAND AFTER THE MALFUNCTION WAS DISCOVERED. SUPPLEMENTAL INFO FROM ACN 522142: THE FO LANDED LONG AS HE HAD AILERON FLT CTL PROBS. I GOT THE MORE EXPERIENCED PLT TO LAND IN AN EMER LNDG. HE WAS DOING FINE UNTIL HE TRIED TO SETTLE THE ACFT ON SMOOTHLY BUT IT FLOATED.

Data retrieved from NASA's ASRS site as of July 2007 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.