A CANADAIR CL65 IN CRUISE AT FL260 DECLARED AN EMER DUE TO LOSS OF AILERON CTL. QRH PROC FREED L YOKE.

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WE WERE OPERATING AS ACR Y FLT XXX; A PART 121 SCHEDULED FLT FROM GSP TO ZZZ. THE ACFT WAS A CL65. THIS PARTICULAR ACFT WAS APPROX 8 YRS OLD WITH OVER 18000 FLT HRS. WE HAD FLOWN 3 CYCLES ON THIS ACFT THE DAY BEFORE AND IT OVERNIGHTED WITH US AT GSP. THE ACFT SAT ON THE RAMP IN A CONTINUOUS SOAKING RAIN THAT NIGHT (APPROX 12 HRS). FLT XXX WAS ORIGINALLY SCHEDULED TO DEPART AT XA30Z; BUT DUE TO A MECHANICAL DISCREPANCY; WE DIDN'T DEPART UNTIL XD10Z. THE DISCREPANCY INVOLVED A PLASTIC GUARD COVER THAT PROTECTED THE R ENG FIRE PUSH SWITCH LIGHT FROM BEING PUSHED INADVERTENTLY. THIS GUARD FELL OFF ITS MOUNTING AND WOULD NOT REATTACH. AFTER A COUPLE OF HRS; CONTRACT MAINT WAS ABLE TO SECURE THE GUARD IN ITS PROPER POS AND SIGNED THE DISCREPANCY OFF IN THE ACFT'S MAINT LOG. ONCE WE WERE UNDERWAY; THE SUBSEQUENT TAXI; TKOF; CLBOUT; AND INITIAL CRUISE WERE UNEVENTFUL. THE FO WAS AT THE CTLS OF THE ACFT. AT APPROX XD30Z; AT FL260; WE RECEIVED THE FIRST OF A SERIES OF REPETITIVE CAUTION MESSAGES ON EICAS. THE R WINDOW HEAT CAUTION MESSAGE APPEARED. WE FOLLOWED THE QRH PROC FOR THE PROB; WHICH IN SHORT; HAD US RECYCLE THE SWITCH TO OFF THEM ON. THIS CLRED THE MESSAGE INITIALLY; BUT MINS LATER IT WOULD REAPPEAR. THIS HAPPENED CONTINUOUSLY UNTIL THE FLT LANDED. AT ABOUT XD37Z WE RECEIVED AN 'AUTOPLT TRIM IS ND' CAUTION MESSAGE. SECONDS LATER IT DISAPPEARED; BUT WAS REPLACED BY AN 'AUTOPLT TRIM IS NU' CAUTION MESSAGE. A FEW MOMENTS PASSED; AND THIS MESSAGE ALSO DISAPPEARED. SINCE THE QRH WAS ALREADY OUT; I INTENDED TO TURN TO THE CTL SYS ABNORMAL SECTION TO SEE WHAT IT SAID ABOUT THE TRIM PROBS WE WERE HAVING. BEFORE I DID THAT; I LOOKED AT THE MFD AND NOTICED THAT WE WERE XING FIX1 INTXN ON THE XYZ ARR AND WE WOULD NEED TO MAKE A 20 DEG L TURN TO INTERCEPT (WE HAD BEEN GIVEN DIRECT FIX1 BY ATC PREVIOUSLY). I LOOKED AND NOTICED THE FLT DIRECTOR COMMANDING THE L TURN TO INTERCEPT. HOWEVER; THE AUTOPLT WAS ONLY INITIATING A 2-3 DEG L BANK. IT WAS NOT KEEPING UP WITH THE FLT DIRECTOR. I POINTED THIS OUT TO THE FO AND REQUESTED THAT HE DESELECT 1/2 BANK AND GO INTO HDG MODE IN ORDER TO GET THE PLANE TO TURN. THERE WAS NO CHANGE. THE FO SUGGESTED TURNING THE AUTOPLT OFF TO TRY TO INITIATE THE TURN MANUALLY. I AGREED; AND WHEN THE AUTOPLT WAS TURNED OFF; THE FO SAID THAT HE WAS UNABLE TO MOVE HIS YOKE. I INITIATED A CHANGE OF CTL AND ATTEMPTED TO TURN USING MY YOKE. IT WAS JAMMED AS WELL; BUT I WAS ABLE TO MOVE IT SLIGHTLY TO THE L AND R -- ENOUGH TO BANK THE PLANE BTWN 5-10 DEGS. PITCH CTL SEEMED NORMAL ON MY SIDE; HOWEVER. I HAD THE FO DECLARE AN EMER AND REQUEST DIRECT TO ZZZ. WE THEN OPENED THE QRH TO THE AILERON SYS JAMMED EMER PROC AND FOLLOWED IT. WE DETERMINED THAT OF BOTH SIDES; MY SIDE HAD MORE AILERON CTL. WE RAN THE CHKLIST ASSUMING THAT MY SIDE WAS THE OPERATIVE SIDE. AFTER COMPLETING IT; MY YOKE WAS ABLE TO MOVE FREELY AGAIN AND THE ACFT RESPONDED ACCORDINGLY ALTHOUGH SOMEWHAT MORE SLUGGISH THAN NORMAL. DURING THE INCIDENT; THE FLT CTL PAGE AND HYD PAGE WERE REFED ON EICAS. NO ABNORMALITIES WERE NOTICED. ONCE ALL CHKLISTS WERE COMPLETE; THE LNDG AT ZZZ WAS UNEVENTFUL. I NOTICED WATER DRIPPING FROM BOTH PANELS POSSIBLY INDICATING THAT ICE HAD ACCUMULATED IN THAT AREA DURING FLT. A MECH ALSO TOLD ME THAT SKYDROL WAS PRESENT ON THE L AILERON INDICATING A POSSIBLE LEAK. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAID THE USE OF THE QRH DIRECTED TO SEPARATE THE CTLS AND THIS ALLOWED THE L YOKE TO FUNCTION. THE RPTR STATED THE PROB WAS LOCATED IN THE R REAR QUADRANT WHERE THE AUTOPLT AND TRIM ACTUATOR SERVOS ARE LOCATED. THE RPTR STATED THE L AND R REAR QUADRANTS ARE LOCATED IN THE MAIN WHEEL WELL FORWARD BULKHEAD AND ARE SUBJECT TO WATER AND DIRECT. THE RPTR SAID THE BEARING IN THE R REAR QUADRANT HAD ABSORBED WATER AND FROZE LIMITING THE MOVEMENT OF THE QUADRANT. THE RPTR STATED A SVC BULLETIN ADVISED THE INSTALLATION OF A SPLASH GUARD COVERING THIS QUADRANT AND WAS ADAPTED AND INSTALLED ABOUT 8 YRS AGO. THE RPTR STATED A CHK OF ALL SPLASH GUARDS IS NOW ONGOING TO DETERMINE CONDITION.