Narrative:

Climbing through FL300, we got an 'autoplt trim rwd' caution message. After resetting the autoplt, the message recurred. When I tried to turn the aircraft back to the course, I realized the aileron control was jammed. The captain's side was also jammed. We ran the QRH procedure for jammed ailerons. After disconnecting the 'roll,' both sides were still unable to move. We declared an emergency and diverted. Upon descent through about 16000 ft, the flight controls broke free. Since we still did not know the nature of the problem, we retained emergency status and requested emergency equipment at ZZZ. The approach and landing were uneventful. Contributing factors may have been very heavy rain at our departure airport. One more note, on landing at ZZZ, the emergency equipment was not rolled, though it had been requested. Callback conversation with reporter revealed the following information: the reporter stated the airplane was taxied for takeoff in a heavy rain shower. Passing through FL300, the autoplt trim rwd caution message illuminated and reset was no help. In trying to move the ailerons, it was discovered no aileron control was possible. The controls were split, but the ailerons were still locked. After declaring an emergency and descending to 16000 ft, the ailerons broke free. The reporter said various methods have been tried to avoid water soaking the aileron components in the main wheel, all unsuccessful.

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Original NASA ASRS Text

Title: A CANADAIR CL65 IN CLB AT FL300 DECLARED AN EMER AND DIVERTED DUE TO LOCKED AILERONS CAUSED BY AILERON UNITS IN MAIN GEAR WELL FROZEN.

Narrative: CLBING THROUGH FL300, WE GOT AN 'AUTOPLT TRIM RWD' CAUTION MSG. AFTER RESETTING THE AUTOPLT, THE MSG RECURRED. WHEN I TRIED TO TURN THE ACFT BACK TO THE COURSE, I REALIZED THE AILERON CTL WAS JAMMED. THE CAPT'S SIDE WAS ALSO JAMMED. WE RAN THE QRH PROCEDURE FOR JAMMED AILERONS. AFTER DISCONNECTING THE 'ROLL,' BOTH SIDES WERE STILL UNABLE TO MOVE. WE DECLARED AN EMER AND DIVERTED. UPON DSCNT THROUGH ABOUT 16000 FT, THE FLT CTLS BROKE FREE. SINCE WE STILL DID NOT KNOW THE NATURE OF THE PROB, WE RETAINED EMER STATUS AND REQUESTED EMER EQUIP AT ZZZ. THE APCH AND LNDG WERE UNEVENTFUL. CONTRIBUTING FACTORS MAY HAVE BEEN VERY HEAVY RAIN AT OUR DEP ARPT. ONE MORE NOTE, ON LNDG AT ZZZ, THE EMER EQUIP WAS NOT ROLLED, THOUGH IT HAD BEEN REQUESTED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE AIRPLANE WAS TAXIED FOR TKOF IN A HEAVY RAIN SHOWER. PASSING THROUGH FL300, THE AUTOPLT TRIM RWD CAUTION MSG ILLUMINATED AND RESET WAS NO HELP. IN TRYING TO MOVE THE AILERONS, IT WAS DISCOVERED NO AILERON CTL WAS POSSIBLE. THE CTLS WERE SPLIT, BUT THE AILERONS WERE STILL LOCKED. AFTER DECLARING AN EMER AND DSNDING TO 16000 FT, THE AILERONS BROKE FREE. THE RPTR SAID VARIOUS METHODS HAVE BEEN TRIED TO AVOID WATER SOAKING THE AILERON COMPONENTS IN THE MAIN WHEEL, ALL UNSUCCESSFUL.

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.