Situation awareness as a function of frame of reference, computer-graphics eyepoint elevation, and geometric field of view

The purpose of this study was to determine how 3 variables for the design of a "heads-down" spatial display--the frame of reference (pilot's eye vs. God's eye), geometric field of view, and elevation of the computer graphics eyepoint--influenced situation awareness. Thirteen flight-naive subjects each flew a simulated F-16 over a computer-generated flight environment to lock onto and intercept a series of sequentially appearing targets. The flight scene consisted of both an "out-the-window" view and a computer-generated heads-down spatial display showing an airplane symbol superimposed on a perspective view of the flight environment. During the interactive phase of the experiment, root mean square flight-path error, target lock-on time, and target acquisition time were measured. After the interactive phase of the study was completed, subjects were required to mark the location of the targets from memory on a computer-generated top-down view of the flight scene in an attempt to reconstruct the spatial mental model which subjects formed of the flight environment. The results for the interactive phase of the study indicated that performance was superior using the pilot's-eye display. However, for the spatial reconstruction task, performance was better using the God's-eye display. It was also shown that the ability to maintain the optimal flight-path using the more top-down view of the scene (600 eyepoint) was superior to the 300 eyepoint elevation. Implications of the results for the design of spatial instruments are discussed.