###### Abstract
Studies show that system safety risks mostly arise from human-computer interaction obstacles, which means errors should not solely be attributed to humans but also to display design [10; 30]. Inappropriate display designs have been shown the potential to weaken an operator's SA and as a result increase the risk of human errors, especially in emergency situations [31]. Therefore, evaluating the utility of an interaction display for supporting an operator's SA in complex and abnormal situations is of particular importance [2; 28; 32]. An operator searches for information based on a specific task goal during execution, which requires that the exact information for decision-making should be visualized directly and accurately in a way that can be captured at first sight [29; 33; 34; 35]. [PERSON] et al. [36] pointed out that one of the critical goals for display design should be to improve the operator's SA, which can effectively promote task performance and reduce human errors. Presently, a series of display design methods, including theoretical models and simulation methods, have been applied to support an operator's SA through optimizing the display content and display layout [37]. Considering the elements of display design, these models and theories point out that the merit of the display design features can be improved by optimizing the interface layout (e.g., rearranging the indicators' location, integration and clutter), enhancing indicators salience (e.g., size, color coding and highlighting border), as well as developing an interactive dashboard and decision-making support display [38; 39; 40; 41]. Thus, there is a necessity to investigate the role of display design elements in influencing an operator's SA and performance in abnormal situations due to unexpected events. Previous studies have pointed out that an operator's SA is vulnerable in abnormal or emergency situations, and as a general principle, display design is expected to provide support for maintaining SA [42; 43; 44]. However, facing abnormal situations, the SA construction process (e.g., attention resource transfer and reallocation) as well as construction result (e.g., behavioral performance and mental workload) have not been fully studied. Meanwhile, the inherent motivations, or the specific causes of capacity decline in cognition and operation, have not been clearly revealed, especially in flight scenarios. What is more, it is also especially necessary to examine whether the interaction displays usually designed based on routine environment can provide effective support in abnormal situations, and we are also interested in what kind of design features of the interaction display is more conducive to maintaining good flight performance, which may provide us with appropriate and feasible technical solutions in interface design [45; 46]. Considering this, this study was aimed to examine the influence of air route alternation and display design on operators' SA, task performance and mental workload during simulated flight tasks, thus providing a basis for improving the measures or principles in optimizing both the standard operating procedures and display designs in response to abnormal situations. Furthermore, participants' eye movement measures were tracked as physiological indicators to reflect the attention allocation processes, as eye movement measures are believed to be related to SA and mental workload [45; 47].