The present thesis is on the subject of electro-hydraulic servo-valve (EHV), and motion and control loading of a flight simulator with EHV. The fundamentals of EHV and hydraulic control systems are discussed in Part A. An electro-hydraulic servo-valve (MOOG 760 series) and a position servo control were constructed using an EHV and a linear hydraulic double-ended cylinder, which was modeled mathematically and implemented symbolically by Simulink.Part B examines the motion and control loading systems of a full flight simulator. Motion simulation algorithms and implementation are discussed in moderate depth. As a generic example, a typical elevator control loading channel is represented in state space; whose stability, linkage compliance and control scheme implementation analysis are conducted in detail by means of MATLAB. The same elevator control loading channel was symbolically modelled through Simulink, based on the EHV/actuator model that was developed in Part A. The results of different control schemes are discussed and compared.