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Capacity at our airports and within en route airspace is limited by the average spacing or distances between aircraft that can be safely accommodated with human-centered control. The average distance between aircraft is influenced by the separation standards and the ability of the Air Navigation Service Provider to precisely control to those standards. Both of these factors are influenced by the technologies and procedures for tactical air traffic management (tactical refers to a 20 minute time horizon) available to the pilot and controller. The Aviation Systems Division conducts leading edge research in the use of tactical air traffic management for reducing separation standards and for precisely controlling to those standards. The research is applied to super-density terminal area and high density en route operations. The Division also conducts research to support environmentally friendly arrivals and user preferred routing.

The research is performed by an interdisciplinary team consisting of experts in automation technologies, optimization and control theory, human factors, systems analysis, and computer science.

Super-Density Operations

Image of Hi-Flow Airports, which shows a Virtual Tower; Automated Surface Movement; Simultaneous Non-interfering Operations; Surface Robotics; Automated, Closely Spaced Formation Flight; and Virtual, Reconfigurable Runways/Taxiways.
Hi-Flow Airports

The Aviation Systems Division identifies innovative applications of tactical air traffic management for: 1) increasing capacity at airports with closely spaced parallel approaches; 2) maximizing the arrival rate at individual runways by assuring the spacing between aircraft spacing on final approach are safely minimized; and 3) integrating arrivals and departures within a metroplex environment to fully utilize all available runways. The research is addressing both the separation standards and the controller's ability to adhere to those standards. This work is being closely coordinated with related work in wake vortex detection and simultaneous use of the same runway.

High Density En Route Operations and Automated Separation Assurance

Image of the concept Advanced Airspace, which shows Collision Avoidance, Free Flight, Flexible Super Sectors, Air/Ground Integration, Voice communications, datalink communications, Tactical Separation Assistance and Unified Traffic Flow Management being provided to aircraft by the Controller, Traffic Management Coordinator and Collaborative Decision Making by Aircraft Operations Centers and Other Transportation Modes.
Advanced Airspace

En route airspace differs significantly from terminal or super-density airspace in that capacity can be increased by a factor of three while adhering to the current separation standards. The primary limitation to en route capacity has been shown to be controller workload associated with maintaining separation assurance. There is sufficient airspace to handle as many as a three times increase in traffic without changing the separation standards. The process of reducing controller workload by reducing sector size has already reached its limit in some parts of the country. A second approach would be to introduce tactical air traffic management automation in the aircraft and ground-based Air Navigation Service Provider system. The Aviation Systems Division is conducting research in the areas of 4D trajectory prediction, conflict detection in the presence of uncertainty, and robust automated resolution logic, and is identifying innovative methods for using automation to enable maintaining separation assurance in the presence of a three times growth in traffic.

In a similar manner, research is being conducted to identify technologies and procedures that would allow user preferred routing under certain traffic conditions. As an example, even under moderately complex traffic scenarios, if a flight wishes to adjust its path or altitude dynamically because of turbulence or other non-planned event and the automated separation assurance logic does not detect a conflict with other traffic, the controller or automation should be able to approve the request.

Environmentally Efficient Operations and User Preferred Routing

Research is also being conducted to identify new technologies and procedures that will enable aircraft to "coast" from cruise to touchdown thereby reducing fuel, emissions and noise. The primary limitation of these techniques is not an aircraft's ability to fly the trajectory but rather how to fly it in the presence of other traffic. The technologies for reduced spacing and maintaining separation assurance introduced under the previous two research areas provide a basis for new technologies that will allow greater choice in the levels of traffic under which the conduction of specialized descents may be accommodated.

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Information on ATM Technology Demonstration - 1.
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Information on Airspace Technology Demonstration - 2.
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Information on the Efficient Descent Advisor.
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Information on the Precision Departure Release Capability.
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Information on Terminal Area Parallel Procedures Research.
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Terminal TSAFE
Information on the Terminal Tactical Separation Assured Flight Environment.
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Tactical ATM Publications
Link to a list of papers available for download.
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Automation for Accommodating Fuel Efficient Descents in Constrained Airspace
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Tailored Arrivals
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NASA - National Aeronautics and Space Administration
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Last Updated: September 18, 2017

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