| Alternative display locations and formats have been investigated to assist pilots perform their tasks. One line of research has shown that pilots perform tasks more effectively when instruments are presented on a head-up display (HUD), helping pilots consult instruments while monitoring the outside scene. However, clutter costs have been revealed when HUDs are used, as elements from the display can mask elements outside the cockpit. Another line of research demonstrated that such costs may be eliminated with conformal elements. These symbols share characteristics (such as contours and motion) with their outside counterparts, and conformality benefits are believed to be due to the pilot's ability to see the displayed element and its counterpart as a fused object.;In the two experiments conducted here, an alternative display format (the pathway display) is tested to determine whether benefits of head-up presentation extend to virtually conformal displays. These displays present information (such as altitude) that is not visible outside the aircraft. Pathway displays graphically present the region of airspace in which the pilot is cleared to fly, and have been shown to promote accurate guidance when used in the conventional head-down location.;Because the pathway display shares motion with outside elements, it was hypothesized that a pathway HUD may enhance tracking and detection when compared to its head-down counterpart. In two experiments, performance with a HUD was compared to performance head-down, and pilots performed a series of simulated tasks in low and high visibility. The results indicate that while detection of events is generally enhanced by the HUD, tracking is influenced by the level of available visual detail when the HUD is used. When little visual detail is visible, tracking performance is equivalent between the two display locations, while the presence of elements of interest (such as airport features) was found to degrade tracking with the HUD. However, when conformal elements are present, tracking is facilitated with the HUD over the head-down location. The results are discussed in terms of space- and object-based models of attention, and future work is defined to further examine how pilots allocate their attention when using virtually conformal displays. |
