Abstract: SA is an important factor influencing the decision-making and operational performance of ATC. In order to explore the objective and effective indicators of the SA of the controllers, an eye-tracking experiment platform to simulate the tower control was built. Three group experiments of varying task difficulty based on the difference of flight number were designed and carried out. NNI algorithm was utilized to quantify subjects' eye-tracking fixation mode. The differences in SA and operational performance between controllers of different NNI fixation features were analyzed comparatively. Results reveal that there is a negative correlation between the SA of the subjects and task difficulty, that the subjects, whose NNI fixation indexes have a discrete distribution, have higher levels of SA and better operational performance, and that the NNI fixation index in the eye movement analysis is a potential indicator of SA in future real-time human factors engineering.

Key words: air traffic controller (ATC), situation awareness (SA), nearest neighbor index (NNI), fixation mode, performance analysis