What was found
DURING APPROACH, CREW NOTICED RUDDER OPERATION WAS EXTREMELY STIFF IN BOTH DIRECTIONS. MAINT INVESTIGATION VERIFIED RUDDER TRAVEL WAS FULL, BUT VERY STIFF WITH OR WITHOUT ELECTRIC POWER. OCCASIONALLY, STIFFNESS WOULD BREAK FREE, THEN RE-ENGAGE. THE RUDDER SERVO WAS DISCONNECTED AND FREE MOVEMENT RESTORED. THE RUDDER SERVO DRIVE OUTPUT CLUTCH WAS FULLY ENGAGED. THE RUDDER SERVO DRIVE WAS REPLACED. SUBMITTER STATED THIS CONDITION COULD HAVE BEEN A DANGEROUS SITUATION HAD THERE BEEN A CROSSWIND OR WHERE RUDDER INPUT WAS REQUIRED.