Task Prioritization And Interruption

As an important part of Crew Resource Management (CRM), Cockpit Task Management (CTM) is the process by which pilots selectively attend to multiple concurrent tasks in an effort to safely and effectively complete the mission, reflecting a task of operating tendency pilots make monitoring, selective attention, the establishment of a priority and handling of special situations at some specific time points. Previous studies have shown that CTM has a major impact on the pilots'unsafe operation and job performance. Accident analysis further showed CTM has become a key influence factor of modern commercial aviation safety. Thus, research on the CTM has not only great significance for understanding the theories of CRM, but also an important value to improve and enhance the safety of the modern aviation.In this study, guided by Funk'CTM model as well as the traditional laboratory findings, we conducted4studies to explore the affecting factors of task prioritization and interruption management by using flight simulation cockpit task. The purpose of this study is to reveal the mechanism of the CTM errors, and to extend further the existing CTM theory, so as to provide an important basis for the work to explore the essential attribute, intervention strategies, and its skills training of human factors.In the first study (Chapter3), two experiments investigated the relationship between the level of automation and task prioritization errors. The experiment1found that the level of automation does not affect task prioritization errors, and cognitive load affects on task prioritization errors; under the high cognitive load condition, the level of automation affects on task prioritization errors. Experiment2found pilots' automation skills do not affect task prioritization errors, but automation resource requirement affected on task prioritization errors. Under the high resource requirement conditions, the level of automation skills has a positive effect on task prioritization errors.In the second study (Chapter4), two experiments investigated the effect of task characteristics on task prioritization errors. Experiment3found that12factors affect task prioritization errors, including:the task status, procedures, rate of change, needed information, urgency, verifying information, importance, time/effort required, salience of display, consequences, resist forgetting, and expectancy. Experiment4further test the effects and found that6factors affect task prioritization errors, followed in descending order by salience, importance, time/effort, urgency, and finally status.In third study (Chapter5), the relationship between the characteristics of task and pilot interruption management performance and its mechanism of reaction investigated by experiment5. It was found that the cue saliency of interrupting task affected the frequency of the switch to the secondary task. Furthermore, pilots flying with the immersive display (tunnel display) were more likely to detect the change in the weather and were easily interrupted by the secondary task when priority was high.Experiment6, in the fourth study (Chapter6), investigated the influence of environmental factors and individual characteristics on interruption management performance. It is found that time pressure affects on interruption management performance. Interruption management performance under no time pressure was significantly higher than it under time pressure. Cognitive style does not affect interruption performance, field independence-pilots more high interrupting task performance than field dependence-pilot. Also, field-independence pilots'interrupting task performance is affected by time pressure; field dependence-pilots'ongoing task performance is affected by time pressure. Type A/B personality affects interruption management performance. Type-A pilots have a higher interrupting task performance than Type-B pilots and are affected by time pressure. Typt-B pilots have a higher ongoing task performance than Typ-A pilots, and the pilots with field-independence have a higher ongoing task performance than the pilots with field dependence.Based on the above four studies, the research the following conclusions:(1) Cognitive load affects task prioritization errors, and also moderates the relationship between the level of automation and task prioritization errors. Resource requirement affects task prioritization errors, and also moderates the relationship between automation skills and task prioritization errors.(2) Six factors affect task prioritization errors, followed in descending order by salience, importance, time/effort, urgency, and finally status.(3) Cue saliency affected the frequency of the switch to the interrupting task. Pilots flying with the immersive display were more likely to detect the change in the weather and were easily interrupted by the interrupting task when priority was high.(4) Time pressure affects both the interrupting task performance and the ongoing task performance. Cognitive style affects the interrupting task performance, and field-independence pilots'interrupting task performance is affected by time pressure; field-dependence pilots'ongoing task performance is affected by time pressure. Type A/B personality affects both the interrupting task performance and the ongoing task performance. Type-A pilots'the interrupting task performance is not affected by time pressure; Type-B pilots'ongoing task performance is affected by his cognitive style.