Pathway HUDs: Are they viable?

We describe two experiments that examine 3D pathway displays in a head-up l ocation for aircraft landing and taxi. We address both guidance performance and pilot strategies in dividing, focusing, and allocating attention betwe en flight path information and event monitoring. In Experiment I the 3D pat hway head-up display (HUD) was compared with a conventional 2D HUD. The for mer was found to produce better guidance, with few costs to event detection . Some evidence was provided that attentional tunneling of the pathway HUD inhibits the detection of unexpected traffic events. In Experiment 2, the p athway display was compared in a head-up versus a head-down location. Excel lent guidance was achieved in both locations. A slight HUD cost for vertica l tracking in the air was offset by a HUD benefit for event detection and f or lateral tracking during taxi (i.e., on the ground). The results of both experiments are interpreted within the framework of object- and space-based theories of visual attention and point to the conclusion that pathway HUDs combine the independent advantages of pathways and HUDs, particularly duri ng ground operations. Actual or potential applications include understandin g the costs and benefits of positioning a 3D pathway display in a head-up l ocation.