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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 August 31, 2021) 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 August 31, 2021.) Saved 1,088,888 gallons of fuel. Saved 22,939,831 pounds of carbon dioxide, which is equivalent to 170,579 urban trees. Saved 5,948 hours of engine run time. Reduced delay by 916.4 hours. Saving passengers an estimated $4,399,066 in value of time and operators an estimated $1,349,907 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 - August 31, 2021)

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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ATD-2 Reaches Over One Million Gallons of Jet Fuel and 150,000 Urban Trees Savings at Charlotte Douglas International Airport
May 19, 2021
On May 16, 2021, NASA’s Airspace Technology Demonstration 2 (ATD-2) Phase 1 and 2 field demonstration at Charlotte Douglas International Airport (CLT), achieved a cumulative savings of one million gallons of jet fuel, since September 2017.
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NASA ATD-2 Phase 3 Stormy 21 Commences Formal Data Collection
April 28, 2021
NASA’s Airspace Technology Demonstration 2 (ATD-2) project entered the 4-month, Phase 3 formal data collection period, entitled Stormy 21, on April 1, 2021.
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NASA Deploys New Capabilities for ATD-2 Phase 3 Field Demonstration
February 10, 2021
On February 3, 2021, NASA’s Airspace Technology Demonstration 2 (ATD-2) team deployed a new version of the Phase 3 Integrated Arrival, Departure, and Surface (IADS) system.
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ATD-2 and ATM-X DIP brief the FAA Flow Evaluation Team and Surface Collaborative Decision Making Team
January 20, 2021
On January 15, NASA's Airspace Technology Demonstration 2 (ATD-2) project briefed the Federal Aviation Administration’s (FAA's) Flow Evaluation Team (FET) and Surface Collaborative Decision Making Team (SCT). Topics covered in this update included the ATD-2 Phase 3 Field Evaluation in the North Texas Metroplex and the introduction to the Air Traffic Management Exploration (ATM-X) Digital Information Platform (DIP) subproject.
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ATD-2 Begins Dissemination of Daily TOS Activity Reports to Field Partners in the D10 Metroplex
January 20, 2021
On January 14, the NASA Airspace Technology Demonstration 2 (ATD-2) team launched the daily dissemination of Trajectory Option Set (TOS) activity reports for the Federal Aviation Administration (FAA), field demo partner airlines such as American Airlines and Envoy Air at Dallas-Fort Worth International Airport (DFW), and Southwest Airlines at Dallas Love Field Airport (DAL) in the D10 Dallas-Fort Worth Metroplex.
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NASA ATD-2 Phase 3 Stormy 2021 Training for DFW Tower and Envoy Airlines
January 20, 2021
The NASA Airspace Technology Demonstration 2 (ATD-2) team provided seven sessions of virtual training to Air Traffic Coordinators at Envoy airlines and Traffic Management Coordinators (TMC) at Dallas-Fort Worth International Airport (DFW) Tower during the first three weeks of December 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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