What was found
(CAN) ON 28 DEC, THE FLIGHT CREW FOR THE SUBJECT AC REPORTED THE ELEVATOR APPEARED TO BE STUCK DURING BASE LEG TO FINAL APPROACH. IT IS UNDERSTOOD THAT WHEN ELEVATOR INPUT WAS MADE, IT TOOK ABOUT 2 SECONDS FOR ANY CORRESPONDING REACTION TO BE OBSERVED RELATIVE TO SURFACE TRAVEL. THIS CONDITION WAS ALSO CONFIRMED ON GROUND BY ON CALL MAINT. AT THE GATE. CUSTOMER WAS UNABLE TO REPORT WHICH CONTROL CIRCUIT WAS AFFECTED BEFORE THE ANOMALY WAS NO LONGER REPEATABLE ON GROUND. THE ELEVATOR SERVO & MOUNT WERE REPLACED. THE SERVO MOUNT IS BELIEVED TO BE THE ROOT CAUSE. THE SERVO WAS REPLACED AS A PRECAUTIONARY MEASURE.