Color Usability on Air Traffic Control Displays

Abstract

Modernization of Air Traffic Control (ATC) display systems includes increased use of color to code information. While colors can enhance display designs, human factors issues like legibility and salience manipulation are still problematic. Here, we address some of the potential usability issues with integrating traffic and advanced weather information on controller displays. We argue that color palettes that are not specifically designed for layered data and a large number of objects can create legibility and salience problems. We discuss the use of luminance contrast to manipulate salience and present some empirical data showing that air traffic controllers display large individual differences in their preferred brightness settings. We argue that user adjustments of luminance contrast for salience manipulation must be severely constrained in future ATC displays. We present a prototype color palette that uses color-coding to prioritize display information while maintaining good legibility.

Weather display symbology affects pilot behavior and decision-making

“…It also complicates the creation of color palettes where all symbols provide sufficient luminance contrast and legibility regardless of background. As long as users must interpret weather symbology, there will always be the classical human factors issues of legibility, salience, color recognition, and display clutter (Ahlstrom, 2005;Ahlstrom and Arend, 2005) in addition to pilot education and training (Lanicci et al, 2012;Wilson and Sloan, 2003). Furthermore, because in-flight weather information is not real-time data, users must be aware of the age of displayed information.…”

“…Modern multifunctional displays can present a wide variety of weather symbols and they also allow pilots to choose different background maps (e.g., VFR, IFR, and terrain maps). This complicates the creation of a salience hierarchy that reflects the urgency of various weather elements with flight hazards getting highest priority followed by other context information like map details (Ahlstrom and Arend, 2005). It also complicates the creation of color palettes where all symbols provide sufficient luminance contrast and legibility regardless of background.…”

“…One such factor is the perceived urgency by which the D1-D3 displays convey weather hazards. We know from previous research on integrated displays (Ahlstrom and Arend, 2005;Arend, 2003) that simultaneous presentations of terrain maps and weather information affect salienced especially in the area of color-coding. In addition, we know that different color combinations can affect the perceived urgency of displayed weather data (Ahlstrom and Arend, 2005).…”

“…Different display symbologies vary in the way they produce symbol clutter and symbol legibility (Ahlstrom and Arend, 2005). Because of this, there can be a differential usage of the display zoom.…”

“…However, as long as users must interpret weather symbols there will always be a potential problem with salience, perceived urgency, display clutter, and so forth (Ahlstrom and Arend, 2005). These are important display issues to resolve because weather symbols need to be readily perceived by users.…”