What was found
(CAN) FLIGHT CREW HAD EXPERIENCED LOSS OF ELEVATOR TRIM TAB CONTROL. UPON INVESTIGATION BY MAINTENANCE, IT WAS FOUND THAT THE PRIMARY TAB CONTROL CABLE HAD WORN AND SEPARATED WHERE IT IS ROUTED THROUGH THE ELEVATOR TRIM TAB SERVO, A PART OF THE INSTALLED AUTOPILOT SYS. DOES NOT APPEAR THAT ANYTHING INTERFERED WITH CABLE ROUTING. NO ABNORMALITIES FOUND WITH THE SERVO CAPSTAN AND THE SERVO IS FUNCTIONING SERVICEABLE. BY DESIGN THE SYS USES THE PRIMARY TRIM TAB CABLE ROUTED THROUGH THE CAPSTAN AND THE ADDITIONAL CABLE LENGTH IS ACHIEVED BY INSTALLING A CABLE EXTENSION, PN 129-500018-13. THIS INSTALLATION DOES NOT USE A BRIDLE CABLE SYS.