Design and Development of the En Route Descent Advisor (EDA) for Conflict-Free Arrival Metering

This paper describes the fundamental design and development of a new decision-support tool for time-based arrival metering, referred to as the En Route Descent Advisor (EDA). This automation is being developed at NASA Ames Research Center as a component of the Center-TRACON Automation System (CTAS). EDA computes advisories for the air-traffic controller to help deliver aircraft to an arrival-metering fix in conformance with a scheduled time-of-arrival constraint, while preventing separation conflicts with other aircraft along the arrival trajectory. The CTAS Traffic Management Advisor (TMA), fielded at numerous facilities in the United States under the FAA Free Flight Phase 1 initiative, computes the scheduled arrival times at the metering fix that EDA targets for optimal throughput into the terminal airspace. By computing strategic maneuver advisories based on speed, altitude, and heading to meet arrival time with a high degree of precision, EDA has the potential to significantly extend the capacity, efficiency, and workload benefits already attributed to TMA operations. The paper first describes the underlying trajectory process, followed by a description of the core meet-time and conflict resolution algorithms employed by EDA. The key aspects of the user interface are then described, which allow controllers to receive, evaluate, and accept EDA advisories at their discretion. Finally, a closed-loop simulation system for evaluating EDA in the laboratory is described, along with key findings obtained during a series of preliminary controller-in-the-loop simulation experiments.