Virtual Reality (VR) and Augmented Reality (AR) Head Worn Display (HWD) technology is being considered as a novel alternative for low cost, wide Field of Regard (FOR), deployable simulators. There are inherent differences in display characteristics among different HWDs and between HWDs in general with conventional displays. For example, the effective Field of View (FOV) in most HWDs is no more than 60° horizontal and 45° vertical, which is far narrower than the human eye's 200° horizontal and 135° vertical FOV. Developing a HWD with a wide 200° horizontal FOV is expensive. Current HWD flight simulator implementations provide limited effective FOV that reduces the pilot's visual stimulus, perception, sense of presence and overall training effectiveness. To successfully utilize a VR or AR HWD in a simulator, we hypothesize the user must have the same or even a higher mental immersion experience as compared with the conventional simulator experience with unrestricted FOV. Attempts to measure mental immersion or presence from VR simulations were normally conducted with questionnaires. Although more convenient, the validity of measuring the continuous experience of presence with post experience questionnaires has been challenged (e.g., Slater, 2004). Here, a quantitative approach to measure presence in relation to mental image processing and performance is proposed. This paper presents experimental methods involving measurement and analysis of normal head and eye movement patterns of experienced pilots while accomplishing specific tasks in a conventional flight simulator with a 170° horizontal x 75° vertical FOR. The paper outlines metrics taken using head and eye tracking equipment, and results of pilot head and eye movement patterns between different Areas of Interest (AOIs) inside and outside the cockpit. The experimental results are analyzed with regard to task performance and five different pilot effective FOV conditions. A summary of findings, experiment limitations, lessons learned and potential areas for future research are also presented.