Terrain-Following with a Head-up Display

Abstract

A head-up display (HUD) was evaluated in simulated low-altitude high-speed terrain-following flight using a four degree of freedom moving-base simulator. An aircraft representative of the RF-4C was programmed as the test vehicle through analog computers associated with the simulator. Six Air Force pilots made a total of 108 one-half hour flights in various terrain, airspeed, and visibility conditions. The pilots' tasks during the flights were to maintain a given clearance altitude and heading at all times. The results showed that terrain-following with the HUD was better than it was with typical in-cockpit instruments. The pilots also preferred the HUD to the in-cockpit instruments, although they felt that numerous improvements could be made to the particular HUD that was used. General findings were that terrain-following efficiency varied with type of terrain, airspeed, and visibility.