As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ENROUTE, CREW NOTICED HYD SYS (A) QUANTITY DECREASING RAPIDLY. SYS (A) HYDR WERE SHUTOFF AND EMERGENCY DECLARED. UPON ARRIVAL AT DESTINATION, A/C REQUIRED TOWING TO RAMP WHERE MAINT DISCOVERED THE AILERON PCU HAD FAILED. THE AILERON PCU WAS REPLACED AND A/C RETURNED TO SERVICE.