Moving Toward An Air Traffic Control Display Standard: Creating A Standardized Target Symbology for Terminal Situation Displays

In this study, we applied human factors best practices to the design of an enhanced target symbol set for terminal displays. To design new symbols, we first identified types of information that would be most operationally useful. We selected four types of information that would provide the greatest operational benefits and tactical support for the controllers. These included aircraft category (Small, Large, Heavy, and Super Heavy), aircraft heading, aircraft altitude, and aircraft conformance to its assigned route or altitude. To evaluate the effectiveness of the symbols, we used search, sorting, and selection tasks that measured symbol preference, reaction time, and symbol identification. Our results indicated that the controllers used consistent heuristics for categorizing symbols into different size and conformance categories. For both the heading and category coding, we also found benefits in terms of both increased accuracy and decreased reaction times. We did not find any benefits for the altitude coding. By using meaningful symbols to convey relevant tactical information, such as aircraft category and heading, we can both increase visual search speed and increase target detection accuracy. On the basis of our findings, we propose a set of symbols and provide recommendations for creating standardized symbology for terminal situation displays and other safety critical systems