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Airspace Technology Demonstration 2 (ATD-2):
Integrated Arrival/Departure/Surface (IADS) Traffic Management

New NASA Field Demo Tests Software to Reduce Airport Delays

NASA-X TV: NASA Field Demo to Reduce Ground Delays Begins

ATD-2 Concept Animation

What is the problem?

Much of the inefficiency in today’s air transportation system can be attributed to a lack of information sharing amongst the operators responsible for managing air traffic in busy terminal environments. Concepts and technologies to improve the handling of arrival, departure, and airport surface traffic have been under development by NASA, the Federal Aviation Administration (FAA), and industry, but to date, these capabilities have largely been developed and implemented independently. NASA’s investigation into the needs of air transportation stakeholders, including airlines, air traffic service providers, airport authorities, and technology vendors, revealed that an integrated approach is needed to address this inefficiency. Without shared information across the operation, a lack of predictability of aircraft movement times persists and leads to overall system inefficiency and greater fuel burn and emissions.

The Airspace Technology Demonstration 2 (ATD-2) effort provides solutions to several problems in the complicated, multi-airport environment. At most airports today, departures are managed in the order they push back from the gate, which can overload runways and cause excessive taxi and hold times.

Additionally, significant uncertainty in the duration of the taxi-out, takeoff, and climb phases of flight leads to inaccurate demand predictions, decreased situational awareness, and overly conservative airspace restrictions that traffic managers are compelled to apply to compensate for this uncertainty.

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What is NASA's solution?

This image shows what a metroplex airspace environment would look like under the ATD-2 concept.
Operational Environment for the ATD-2 Concept (Click image to enlarge.)

Working with the FAA and industry, NASA has developed an integrated arrival, departure, and surface (IADS) concept and technology to demonstrate the benefits of an IADS traffic management system for complex terminal environments. ATD-2 leverages previous investments by NASA, the FAA, and industry, including the FAA’s three major operational decision support system technologies (Traffic Flow Management System (TFMS), Time Based Flow Management (TBFM), and Terminal Flight Data Management (TFDM)).

The ATD-2 Field Demonstration will preview several aspects of the under-development TFDM system such as Surface Collaborative Decision Making (Surface CDM) departure metering, the Electronic Flight Data user interface in the airport tower, and data sharing with industry via the TFDM Terminal Publication (TTP) service.

NASA’s ATD-2 IADS System improves the efficiency of surface operations at the nation’s busiest airports through time-based metering of departures and improved sharing of flight operations information amongst the various airport surface stakeholders. ATD-2 departure metering recommends holding some departing flights a little longer at the gate instead of having them wait in long departure queues at the end of the runway. Shifting some of the departure wait time from the taxiway to the gate saves fuel, reduces emissions, and gives airlines and passengers more flexibility in the period prior to pushback.

The ATD-2 IADS System also couples a trajectory-based surface decision support tool (similar to TFDM) with the overhead stream insertion capabilities of the TBFM en route metering decision support system. The result is more precise scheduling of surface departures into constrained overhead flows, better communication between the en route and tower controllers, and significant improvement in compliance with target takeoff times.

Photograph of a TMC in the ATCT at CLT viewing displays with ATD-2 tools. The user's back is to the camera as he looks out of the tower windows. He is holding a phone to his ear.
A Traffic Management Coordinator (TMC) in the air traffic control tower at CLT (shown here) uses ATD-2 tools to coordinate departure release times with a TMC in the en route Center.

Photo of a ramp manager at CLT looking at a display of the ATD-2 Ramp Manager Traffic Console.
A ramp manager at CLT uses the ATD-2 IADS System to implement departure metering in collaboration with TMCs in the air traffic control tower.

The NASA-FAA ATD-2 field demonstration is being conducted in three phases. The first baseline IADS phase commenced on September 29, 2017 and demonstrates tactical surface departure metering at the American Airlines ramp tower and FAA’s Air Traffic Control Tower at Charlotte-Douglas International Airport, as well as overhead stream insertion at Washington Air Route Traffic Control Center. The next phase extends the surface departure metering time horizon with strategic planning tools, interfaces with tower controller electronic flight strips, and expands overhead stream insertion to Atlanta Air Route Traffic Control Center. The final phase demonstrates a Terminal Departure Scheduling capability that considers multiple airports and terminal boundary constraints. This third phase will be conducted at Dallas/Fort Worth Terminal Radar Approach Control, Fort Worth Air Route Traffic Control Center, Dallas/Fort Worth (DFW) and Dallas Love Field (DAL) Air Traffic Control Towers, and American and Southwest Airlines facilities at DFW and DAL airports, respectively.

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What are the benefits?

Field demonstration results of departure metering from Phase 1 and Phase 2 thus far (September 29, 2017 through January 31, 2020) suggest that the ATD-2 IADS System saves fuel and emissions, reduces congestion on taxiways, and improves compliance with scheduled takeoff times for managing overhead stream insertion.

Benefits totals from Phases 1 and 2 of the ATD-2 field demonstration at Charlotte Douglas International Airport (September 29, 2017 through January 31, 2020.) Saved 652,613 gallons of fuel. Saved 13,487,415 pounds of carbon dioxide, which is equivalent to 100,292 urban trees. Saved 3,317 hours of engine run time. Reduced delay by 557 hours. Saving passengers an estimated $2,673,697 in value of time and operators an estimated $757,627 in flight crew costs.
Benefits totals of the ATD-2 field demonstration at Charlotte Douglas International Airport from Phases 1 and 2 thus far (September 29, 2017 - January 31, 2020)

At the end of each demonstration phase, NASA will provide an ATD-2 technology transfer to the FAA and industry partners.

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ATD-2 Remote Demos

The ATD-2 team conducts periodic demonstrations of system capabilities. These demos are held live online and will be recorded for watching later.
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NASA X TV: Airspace Technology Demonstrations (ATD) Project

The Airspace Technology Demonstrations (ATD) Project is comprised of technology development and demonstration activities geared toward delivery of near-term benefits to air transportation systems. Arrival, departure and surface activity including terminal sequencing and spacing and air traffic flow management are several of the projects NASA is working on to make air travel safer and more reliable. Watch the NASA X video to learn more.
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Airspace Technology Demonstration 2 (ATD-2) Machine Learning Services Featured at NASA Data Science Month
September 23, 2020
NASA Data Science Month is structured as a multi-day, virtual mini-conference hosted by the NASA Headquarters Information Technology and Communications Division (ITCD) and Johnson Space Center Information Resources Directorate (IRD).
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ATD-2 Experience Shared on Air Traffic Control Association (ATCA) Technical Symposium S.M.A.R.T Airport Panel
September 23, 2020
The Air Traffic Controllers Association (ATCA) Technical Symposium hosted a panel session entitled “Self-Monitoring and Reporting Technology (SMART): Intelligent Airports and the Technology That Enables Them,” on September 15, 2020.
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ATD-2 Stormy 2021 Briefing to the Surface CDM Team (SCT) & Flow Evaluation Team (FET)
September 23, 2020
Representatives from the NASA Airspace Technology Demonstration 2 (ATD-2) team briefed plans for Trajectory Options Set (TOS) Stormy 2021 testing during a joint meeting of the SCT and FET teams on September 14, 2020.
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ATD-2 Phase 3 Stormy 21 Kick Off Meeting
September 3, 2020
The NASA Airspace Technology Demonstration 2 (ATD-2) team conducted a “Stormy 21” virtual planning meeting with field demo partners in the North Texas area, on August 26, 2020.
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NASA ATD-2 Phase 3 Stormy 2021 Training for Envoy Airlines
August 5, 2020
The NASA Airspace Technology Demonstration 2 (ATD-2) team provided two sessions of virtual training to Air Traffic Coordinators at Envoy Airlines in July 2020.
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NASA ATD-2 Phase 3 Stormy 2020 Training Videos and Presentations
July 8, 2020
The NASA Airspace Technology Demonstration 2 (ATD-2) team has adjusted its training practices in response to the COVID-19 working conditions and visitor restrictions, in place since March 2020.
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NASA ATD-2 Phase 3 Stormy 2020 Kick Off Meeting
April 2, 2020
The NASA Airspace Technology Demonstration 2 (ATD-2) team conducted a Stormy 2020 kick off meeting with field operators in the North Texas area on March 19, 2020.
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Integrated Arrivals, Departures, and Surface (IADS) Operations Publications
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NASA Fact Sheet
Download the NASA Fact Sheet on ATD-2.
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