Responses of Pilots and Nonpilots to Color-coded Altitude Information in a Cockpit Display of Traffic Information

Abstract

The effective use of cockpit displays of traffic information is largely dependent upon the degree to which vertical status and trend information can be presented simply and unambiguously to the pilot. The traditional use of plan-view displays has been challenged by other representations, each having its own unique advantages and disadvantages. Although perspective-view displays, for example, may be very useful, they suffer from potential overlaid symbology causing obscuration or clutter along specific viewing vectors. An alternate approach is to use color encoding techniques to represent vertical trend information in a plan-view horizontal situation display. Static and dynamic color coding techniques were used in such a display where stratified vertical sectors were represented by stereotypic colors (green/safe; yellow/caution; red/danger) with an additional color cue for intruder above/below. The static representation depicted the symbol in the appropriate color or a 50/50 combination of colors to represent transitions between zones. The dynamic presentation used a continuously changing ratio of colors within the symbol to show this same transition between altitude zones as an attempt to provide rate and depth-of-penetration cues. Performances of nonpilots and pilots using these displays were obtained in a simulation setting and compared with performances obtained using numeric/symbolic encoding of the same information. The color-encoded conditions generally produced faster and more accurate classification responses than did the numeric/symbolic condition. Pilot course tracking behavior, however, was not affected differentially across display formats.