Compared to aircraft, flight simulators are severely limited in their motion envelopes. Presenting the true aircraft motion one-to-one on flight simulators is generally impossible and it is therefore common practice that these motion stimuli are only presented in reduced and attenuated form. Because of a limited understanding of human motion perception processes and how these affect the perceived realism of the multimodal stimuli pilots are subjected to during aircraft control (most notably, visual and physical motion stimuli), the definition of requirements for flight simulator motion cueing fidelity is a problem that researchers and legislators have struggled with for years. This thesis therefore describes and evaluates an objective method for the assessment of simulator cueing motion fidelity. The proposed method is centered around an analysis of the control dynamics adopted by pilots during manual control tasks, and how they use visual and motion stimuli in their selected control strategy, using multimodal pilot models. This approach thereby allows for the objective and quantitative evaluation of flight simulator motion fidelity, by explicitly considering how degraded motion cueing fidelity affects a simulator's ability to induce real-flight manual control behavior. This thesis describes a number of experiments in which pilot manual control behavior was measured using this approach in the Cessna Citation II laboratory aircraft and the SIMONA Research Simulator at Delft University of Technology. A comparison of the collected measurements clearly shows that variations in simulator motion cueing fidelity result in changes in pilot manual control behavior. With increased motion cueing fidelity, pilots are seen to rely significantly more on the presented motion stimuli, a control strategy that also typically results in increased manual control performance. Furthermore, these experiments also show that important behavioral parameters that characterize the weighing of visual and motion information by pilots also correspond best with those measured for in-flight pilot behavior when simulator motion cues are close to those of real flight.