Traffic complexity of intersecting flows of aircraft under variations of pilot preferences in maneuver choice

This paper studies the traffic complexity of two intersecting flows of aircraft when the pilot maneuver preferences vary. The traffic complexity is indicated by the amount of airspace required for the conflict-free crossing of the two flows. To simplify the analysis, we use the models of instantaneous lateral and longitudinal position changes to approximate the heading-change and speed-change maneuvers of the aircraft, respectively. The pilot preferences, expressed as preferred heading or speed changes, are reflected by different penalty functions of position displacements that the pilots attempt to minimize during conflict resolution. Under the same pilot preferences, the aircraft flow stability is preserved using a decentralized conflict-resolution scheme. However, when the pilot preferences are allowed to vary so that individual aircraft have more control freedom in conflict resolution, the traffic complex is shown to increase significantly in the sense that the intersecting flows require a much larger fraction of airspace to ensure conflict-free and stable flows of aircraft.