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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?

Preliminary Phase 1 field demonstration results from the first 4 months of departure metering 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.
  • The IADS System, on average, saves up to 1,000 pounds of fuel during each metered departure bank (CLT typically has nine banks per day) and reduces carbon dioxide emissions by up to 3,000 pounds, which is equivalent to planting 36 urban trees.
  • Initial analysis indicates that the IADS System, at a minimum, does no harm to the ability of flights to depart the airport on time even with the additional gate holding and may actually improve on-time performance. Analysis showed that using the IADS System resulted in a 15% improvement in the number of flights departing within their airline-scheduled departure block times.
Over and above the departure metering benefits, analysis of two-months of overhead stream insertion data showed:
  • Controllers reduced departure delays for 172 flights by a total of 22.5 hours by electronically renegotiating takeoff times using the IADS System.
  • In addition, up to 43,000 pounds of fuel was saved when ramp controllers used the IADS System to advise gate pushback times for flights in order to meet their scheduled takeoff times more efficiently.
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 Completes Assessment of Ramp Times 3 Shakedown Simulation
April 3, 2019
The Airspace Technology Demonstration 2 (ATD-2) experiment team completed the Assessment of Ramp Times (ART) 3 human-in-the-loop (HITL) shakedown simulation, March 26-28, 2019, at NASA Ames Research Center’s FutureFlight Central (FFC).
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Technical Exchange with FAA Systems Analysis and Modeling Division Manager
April 3, 2019
On March 29, 2019, the NASA Airspace Technology Demonstration 2 (ATD-2) team held a technical interchange meeting with Mr. David Knorr, the Manager of the Federal Aviation Administration (FAA) Systems Analysis and Modeling Division, which is responsible for developing a Post Operational Assessment of key NextGen capabilities.
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ATD-2 Presents Phase 3 Concept of Use to the Collaborative Decision Making (CDM) - Flow Evaluation Team
December 20, 2018
NASA briefed the Airspace Technology Demonstration 2 (ATD-2) Phase 3 Concept of Use to the CDM Flow Evaluation Team (FET) on December 6, 2018 in Washington, DC.
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ATD-2 Briefing at Collaborative Site Implementation Team (CSIT) Meeting
December 12, 2018
American Airlines (AAL) and Southwest Airlines (SWA) hosted the Federal Aviation Administration (FAA) Collaborative Site Implementation Team (CSIT) meeting, December 4-5, 2018.
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NASA ATD-2 Team Briefs the System Wide Information Management (SWIM) Industry-FAA Team (SWIFT)
November 21, 2018
On November 15, 2018, the NASA Airspace Technology Demonstration 2 (ATD-2) subproject participated in the Federal Aviation Administration (FAA)-hosted SWIFT team event in Washington D.C.
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ATD-2 Briefing at Collaborative Site Implementation Team (CSIT) meeting
November 8, 2018
On October 16-17, 2018, members from the NASA Airspace Technology Demonstration 2 (ATD-2) team participated in a Federal Aviation Administration (FAA) Collaborative Site Implementation Team (CSIT) meeting hosted by Delta Airlines (DAL) at their headquarters in Atlanta, Georgia.
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Two-Way Information Exchange with General Aviation Pilots Through Mobile Application Technology with NASA ATD-2
November 8, 2018
On November 5, 2018, two-way information exchange with the NASA Airspace Technology Demonstration 2 (ATD-2) system was enabled with General Aviation (GA) operations at Charlotte-Douglas International Airport (CLT) by leveraging The MITRE Corporation’s mobile application.
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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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Last Updated: April 8, 2019

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