Effects of Modern Primary Flight Display Clutter

Abstract

Many complex domains, including aviation, experience a continued increase in the amount of information that is needed and available to operators. One example of this trend is modern primary flight displays (PFD), some of which now include weather, terrain, and navigation data. The addition of information to already busy displays has raised concerns about clutter. In this experiment, our goal was to investigate the performance and attentional costs associated with PFD clutter during a simulated flight and to determine to what extent pilots are aware of clutter and its effects. Low-, medium-, and high-clutter PFDs were created, and pilots flew a simulated flight scenario containing periods of high and low workload using one of the three PFDs. Pilots were asked to detect various visual alerts and notifications that appeared on the PFD throughout the flight. Performance, eye tracking, and subjective measures were recorded. Clutter significantly increased the response time to alerts, and high workload resulted in more alerts being missed. The eye tracking data provided insight into pilots’ monitoring strategies and efficiency in the different clutter conditions. Spatial density and the number of transitions were found to be larger in the case of higher clutter, whereas the number of fixations on flight mode annunciators was higher in the low-clutter condition. Importantly, pilots rated clutter as being relatively low even in the high-clutter condition. In combination, these results suggest that pilots may benefit from real-time clutter detection and reduction techniques that are based on eye tracking metrics.