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EDA - En Route Descent Advisor

Overview

The En Route Descent Advisor (EDA) is a CTAS tool that assists controllers with metering arrival aircraft in transition from Center to TRACON airspace. Specifically, EDA generates maneuver advisories to deliver aircraft very accurately to an arrival-metering fix located at the TRACON boundary. EDA works in conjunction with the CTAS Traffic Management Advisor (TMA), which generates the precise schedules and sequences that EDA targets for optimal throughput into the TRACON. EDA is capable of generating explicit "meet-time" maneuver advisories based on combinations of speed, altitude, and heading degrees of freedom. EDA constructs advisories that satisfy ATC constraints while remaining as fuel-efficient as possible for airspace users. In addition to its meet-time capabilities, EDA provides automated conflict resolution by presenting advisories that are predicted to put aircraft on conflict-free trajectories to the metering fix. By making use of accurate CTAS trajectory predictions involving aircraft type, atmosphere, and procedures, EDA supports both strategic and tactical decision-making with time horizons up to 25 minutes.

Benefits

Studies suggest that EDA can lead to substantial benefits in capacity, fuel-efficiency, and controller productivity. Capacity benefits are achieved through accurate TRACON delivery in accordance with a TMA plan that is optimized for maximum throughput to the runway. Fuel efficiency is achieved through EDA's minimum-fuel trajectory planning algorithms, similar to those found in aircraft Flight Management Systems (FMS). Controller and airspace-user benefits are derived from the predictive capabilities of EDA, which allow for metering problems to be resolved upstream in a more strategic manner than is possible today without automation. Early detection and resolution of metering-related problems can help achieve a more equitable distribution of controller workload between upstream and downstream sectors. With assistance from EDA under high-workload metering conditions, controllers will be able to focus additional attention on non-metering tasks, such as responding to changing weather and airspace conditions, and accommodating user route preferences.

Research & Development

EDA research is supported by NASA's Airspace Systems Program. EDA is being implemented within CTAS through a series of prototype builds. An initial prototype has been implemented within the CTAS research baseline. Through 2005, the EDA prototype will be refined through a series of controller-in-the-loop simulations at NASA Ames Research Center. Beyond 2005, a pre-production prototype will be completed through ARTCC field-test evaluation and integration with the FAA Display System Replacement (DSR). Following initial deployment, EDA will be augmented with air/ground data-link capabilities in order to achieve additional benefits to controllers and airspace users.

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