Abstract: Lineofsight stabilization is a key specification for stabilized sighting system. With manual tracking as research subject, the model of stabilization servo control system was established based on the concept of two gimbals, four axes design. Based on the helicopter scenario, the mathematical models were also built for disturbances such as linear disturbance, angle disturbance, friction and elastic torque. Matlab software was used to simulate the manual tracking mode of the airborne stabilized sighting system under various disturbance torques. A suitable controller was designed. The model is verified in real system and could be used in servo control design.