Dual-Task Performance Consequences of Imperfect Alerting Associated With a Cockpit Display of Traffic Information

Abstract

Performance consequences related to integrating an imperfect alert within a complex task domain were examined in two experiments. Cockpit displays of traffic information (CDTIs) are being designed for use in airplane cockpits as responsibility for safe separation becomes shared between pilots and controllers. Of interest in this work is how characteristics of the alarm system such as threshold, modality, and number of alert levels impact concurrent task (flight control) performance and response to potential conflicts. Student pilots performed a tracking task analogous to flight control while simultaneously monitoring for air traffic conflicts with the aid of a CDTI alert as the threshold, modality, and level of alert was varied. As the alerting system became more prone to false alerts, pilot compliance decreased and concurrent performance improved. There was some evidence of auditory preemption with auditory alerts as the false alarm rate increased. Finally, there was no benefit to a three-level system over a two-level system. There is justification for increased false alarm rates, as miss-prone systems appear to be costly. The 4:1 false alarm to miss ratio employed here improved accuracy and concurrent task performance. More research needs to address the potential benefits of likelihood alerting. The issues addressed in this research can be applied to any imperfect alerting system such as in aviation, driving, or air traffic control. It is crucial to understand the performance consequences of new technology and the efficacy of potential mitigating design features within the specific context desired.