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Drawing for the Expedite Departure Path (EDP) concept

Overview of EDP

Automated advisory tools designed to meet the departure problems are in an early phase of concept definition, and are currently referred to as Expedite Departure Path (EDP) tools. EDP will make use of the aircraft performance-model-based trajectory planning capabilities of CTAS to provide an advisory decision support capability to assist controllers in:
  • Load management for departing traffic
  • Sequencing, spacing, and merging of departing aircraft into the en route traffic stream
EDP will aid traffic management specialists in the Traffic Management Unit (TMU) as well as sector controllers in terminal, en route, tower, and/or airline operational control facilities. Local facility procedures will be incorporated into EDP. Initial functionality will provide departure management assistance to TRACON controllers with en route functionality to be provided in the future.

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Expected Benefits

Benefits are dependent on:
  • Traffic loading of airport(s)
  • The dependencies of arrivals and departures at an airport
  • Traffic flow between multiple airports within a TRACON and in the extended terminal area.
Airspace User Benefits:
  • Reduced aircraft fuel burn and block times due to improved departure trajectories and improved coordination of aircraft from satellite airports. (Note: This could have significant benefits for General Aviation aircraft.)
  • Reduced taxi delay
Airspace Traffic Service Benefits:
  • TRACON capacity improvements through more effective balancing and sequencing of arrival and departure traffic (for airports either having dependent arrival and departure runways or runways that simultaneously handle arrival and departure operations).
  • Improved runway systems utilization
  • Reduced tower-to-tower verbal communication, especially in dependent departure situations (e.g., OAK-SFO; Northeast Corridor)
Community Benefits:
  • Reduced community noise impact
  • Reduced emissions and fossil fuel expenditure
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System Function

The following near-term functionality has been proposed for EDP:
  • Provide aircraft sequencing and departure gate balancing information to TRACON traffic management coordinators.
  • Utilize conflict probe functionality to expedite departures that cross arrival routes by determining when unrestricted climbs can be given to specified aircraft (in en route airspace).
  • Meter and/or provide clearance advisories for departing aircraft that merge over a given fix.
  • Provide accurate flying time estimates to surface-based departure planning systems.
  • Provide conflict-free, fuel-efficient speed and turn advisories to improve utilization of terminal airspace.
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Previous Tool Functionality History

The EDP will use aircraft performance-model-based four-dimensional trajectory prediction previously developed for the CTAS TMA and EDA. Trajectory profile selection and clearance advisories developed for FAST will be employed in the TRACON tool component. The EDP will emply conflict prediction technology developed for the CTAS EDA and Direct-to, as well as a knowledge-based conflict resolution scheme shared by Active FAST.

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Current Status

The EDP is in the concept exploration phase, and initial human factors studies have been completed. Some initial concept development work and preliminary potential benefits studies are underway as well as preparations for controller-in-the-loop simulations. + Back to Top
EDP Publications
Link to a list of EDP papers available for download.
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Last Updated: October 13, 2016

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