Application of a three-dimensional auditory display in a flight task.

The effectiveness of a three-dimensional (3D) auditory display in conveying directional information was investigated in a flight simulation experiment. While flying a simulated fighter aircraft, participants followed a target aircraft that suddenly disappeared and reemerged at an unknown position. The task was to locate and trail the target as quickly as possible. In all conditions the participants viewed a computer-generated outside image, on which they could spot the target only when it was at short range, and a three-dimensional (3D) tactical display indicating the target position at all distances within a limited field of view. Additional displays were a bird's-eye-view radar display, which also indicated whether the target was above or below the own plane, and a 3D auditory display, which generated a warning sound from the relative direction of the target. The auditory display used individualized head-related transfer functions to create a virtual sound source and a head-tracking device to decouple the position of the source from head movements. Results show that the radar and auditory displays caused about the same significant reduction in search time in comparison with the tactical display only. A further reduction was found when the two additional displays were presented simultaneously.