Expanding the Envelope of Performance: Training Pilots to Use Helmet Mounted Displays

Abstract

Helmet Mounted flight Displays (HMDs) of a through-the-window field-of-view (FOV) are widely used in modern aircraft for night vision. Unfortunately, pilots using such displays are susceptible to spatial disorientation due to the limited field-of-view and its consequent lack of orientation cues. This problem is especially pronounced when pilots move their heads, though this is precisely the behavior that enables them to counteract the limited FOV. The current experiment attempted to train pilots to move their heads without becoming disoriented. Twenty-five subjects participated in five treatment groups in a between-subjects design. Subjects piloted a simulated helicopter through a computer-generated winding canyon with either a single-eye HMD, or a binocular through-the-window “screen” display. Three control groups were trained using either (1) a binocular screen-display without a secondary task, (2) an HMD view without a secondary task, or (3) an HMD view with a secondary task presented in the center of the HMD FOV. The two remaining treatment conditions involved flying while carrying out a secondary task which required either (1) systematic head movement (displacement), or (2) systematic head-movement plus head re-orientation. Results indicate that after training, treatment groups completed significantly more flights without crashing using the HMD than did the control groups. They also had a significantly higher probability of surviving a given flight at any time. Treatment groups learned to increase their head movement, while control groups spontaneously reduced theirs. These findings indicate that spontaneous experience with an HMD does not lead to optimal performance. Development of attention control strategies focusing on the difficulties of HMDs increased considerably the ability of operators to cope with the problems.