Three color schemes (monochrome, dichrome, and polychrome) based on basic principles for color perception and cognition were optimized and applied to an electronic map in a horizontal-situation display. Principles for color discrimination, symbol coding, and color naming were applied for the super-imposed symbols (targets, waypoints etc) and for the map symbology (land, water, roads). The color codes were tested in a visual search and detection experiment in a real-time simulation in an air-to-air mission with test pilots as subjects. The simulation task was as close as possible to a real-life situation. The pilots had to track a maneuvering target within specific limits. Reaction times for target detection were recorded. After the simulation, the test pilots gave a subjective estimation of the different color schemes. They also estimated them according to situation awareness using a rating technique on cognitive compatibility (CC-SART). All the results, both the objective and the subjective show that color schemes are advantageous in comparison to the monochrome code. The reaction times were significantly lower for the chromatic color codes. The estimated situation awareness was higher for the chromatic schemes and the subjects gave higher preferences to the chromatic codes.