Merge Support for Fixed Trajectories and Vectored Traffic in Approach Air Traffic Control

Abstract

Current approach control at Schiphol is mainly based on radar vectors, which offer high flexibility to the air traffic controller. New technologies such as Required Navigation Performance - Authorization Required enable fixed approach routes with curved segments to be flown with high precision. While fixed approach routes are desirable to reduce track miles, to enable continuous descents, and to avoid noise-sensitive areas, decision support is currently only available on the final approach leg whereas earlier support is needed. The shift to fixed routes requires a decision support tool to merge different approach types without increasing the workload. In this paper, the design of the Final Merge Tool (FMT) is presented, which combines projections of downwind traffic with separation markers on the final approach leg. It uses a time-based prediction algorithm and integrates the projections in the existing support tool. The FMT interface is evaluated in a first exploratory real-time simulation with four professional air traffic controllers from the Netherlands Air Traffic Control, comparing different mixes of traffic on fixed routes versus vectored traffic. Results from this evaluation show that the number of commands issued decreased with the tool and that the subjective workload was lower. Controllers were able to use their own strategies with the tool and generally found the support helpful for determining the sequence on final approach. There were no indications that the tool decreased safety, but further research is needed to confirm this with more certainty.