Citation Excel (C560XL)
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical
Flight Crew Overcame Equipment Problem; General Maintenance Action
Aircraft
We conducted a flight [that was] 3+ hours at FL400. With the autopilot and yaw dampener turned off on final approach; the flying pilot (RP) noted the rudder pedals were hard or frozen. He was able to make an uneventful landing.  Once safely on the runway; the flight controls were passed to the non flying pilot (LP) to confirm the rudder pedal situation. The non flying pilot confirmed the hard or frozen pedals. Once slowed to a safe speed; the rudder pedals broke free and we were able to taxi to the ramp without further issues or assistance.  The rudder still felt stiff and required more input than normal to operate; but did not endanger the taxi operations. Once the aircraft was powered down; the rudder pedals still had the same stiffness that was noted on the taxi.
The reporter states that a definitive cause for the frozen rudder control has not been reported to him. He is of the opinion though that this event is similar to others previously reported and was likely caused by ice on the control cables.
CE560 Captain reports stiff or frozen rudder pedals during approach with the autopilot and yaw dampers turned off. After landing the pedals become less stiff and the aircraft is taxied to the ramp.