Navigation in Terrain-Following Flight

This study investigated the problem of navigation in low-altitude, high-speed, terrain-following flight. Tests were made in a four-degree-of-freedom flight simulator that had an out-of-cockpit television presentation synchronized with it in such a way that a subject seemed to be flying over a landscape with freedom to climb, descend, and change course at will. Twelve experienced jet pilots flew 48 one-and-one-half-hour missions using several combinations of navigational and terrain-following displays in two different types of simulated aircraft. The results showed that the pilots navigated with much greater efficiency when they had information from a simulated inertial guidance system than when they did not have this information. They navigated better in mountainous terrain when they used a head-up display for terrain-following than when they used conventional in-cockpit instruments for terrain-following, and they navigated better in the aircraft that had the more desirable handling qualities.