Assisting Air Traffic Controllers in Planning and Monitoring Continuous-Descent Approaches

Abstract

An interface was developed to assist controllers in metering, sequencing and merging aircraft flying a Continuous Descent Approach. This Time-Space Diagram displays predicted aircraft approach trajectories in a way that allows controllers a better insight into the separation between aircraft flying continuous descents. The paper discusses how a baseline Time-Space Diagram display can be enhanced with ‘whatif’ predictions, providing support for routine controller spacing techniques such as speed instructions and the use of direct-to commands. An experiment with eight professional air traffic controllers compared the Time-Space Diagram to a conventional plan view display in low and high traffic rate scenarios. Use of the Time-Space Diagram display yielded a significant reduction in controller workload. It also reduced the number of instructions to the pilots, suggesting a reduced workload for the flight deck as well. Controllers’ opinions on the usefulness of the ‘what-if’ predictions were mixed, and these additions did not lead to any significant performance improvements.