An Information-Center ed Analysis of the Tunnel-in-the-Sky Display, Part 3: The Interception of Curved Trajectories

Abstract

Companion papers (Mulder , 2003a) and (Mulder , 2003b) studied pilot control behavior with the tunnel-in-the-sky display in the regulation task of following trajectories that were straight or curved, respectively. This article investigates pilot decision making in the anticipatory task of intercepting a curved section of the trajectory. A fixed-base simulator experiment was run to study the pilot's timing of the curve interception maneuver . Different tunnel display geometries, aircraft types, and flight speeds were simulated. Presenting the tunnel frames allows pilots to use a tau (time-to-contact) strategy afforded by the expansion of the tunnel frames to determine the time-to-go to the curve. Presenting only the tunnel outline induces the use of the tangent point, the innermost point of the curve, to time the maneuver, a strategy reported in automobile driving research. It is shown that the display formats presenting the tunnel frames yield consistent timing behavior and were preferred by pilots. Presenting only the tunnel outline resulted in large variations in conducting the maneuver accompanied by a poor path-following performance and a high pilot workload. Hence, tunnel displays are recommended to include a sufficient number of frames near the transitions between curved and straight sections.