Visual search performance during simulated radar observation with and without sweepline.

PDFTech ReportFAA-AM-79-12DOT/FAA/AM-79/12Air traffic controlAutomated radar terminal systemAttentionEye movementsPerformanceVigilanceAutomationMonitoringFatigue (Physiological condition)ExperimentsHuman subject testingUnited StatesCivil Aerospace Medical InstituteThackray, Richard I.Touchstone, R. MarkCivil Aeromedical InstituteUnited States. Office of Aviation MedicineNTL-AVIATION-Air Traffic ControlNTL-AVIATION-Aviation Human FactorsUS Transportation CollectionA study was conducted to determine whether or not the presence or absence of a radar sweepline influences attentional processes and, hence, the speed with which critical stimuli can be detected. The visual display was designed to approximate an advanced, highly automated air traffic control radar display containing computer-generated alphanumeric symbols.Twenty-eight men and women, paid volunteers with no previous air traffic controller experience, were tested over a 2-hour session with half of the subjects assigned to the sweep condition and half to the no-sweep condition. Sixteen targets appeared on the screen at all times, with 10 signals (a designed change in the alphanumerics) randomly presented during each 1/2-hour of the test session. Mean detection latencies, long detection times, and missed signals all increased significantly over the task session.Although the no-sweep appeared to be generally superior to the sweep condition in all measures of detection efficiency, none of the differences was significant. Concomitantly recorded measures of saccadic eye movements revealed a pattern of change in mean fixation duration which paralleled the patterns of change in performance during the task session. However, as with performance, mean fixation durations for the sweep and no-sweep conditions did not differ, nor were individual differences in scanning activity related to performance. Possible reasons for the lack of relationship between scanning activity and performance are discussed