If every commuter drove the same few roads at the same time every day, the traffic would be unbearable. That’s exactly what’s happening in the skies above the nation, called the national airspace (NAS). Multiple flights from different airlines try to use the most direct flight paths, converging on the same airports. With limited runway space, that causes jumbo-sized traffic congestion. So, NASA worked with the Federal Aviation Administration (FAA), commercial airlines, and airports to develop and test a new program to manage airport traffic on the ground — the Integrated Arrival, Departure, and Surface (IADS) system. In 2022, the FAA began incorporating IADS capabilities at 27 of the busiest airports in the country.
“The majority of uncertainty in the NAS can be attributed to surface operations, and in particular, uncertainty related to when a flight will be available to push back from the gate,” said Jeremy Coupe of NASA’s Ames Research Center in Silicon Valley, CA, who served as the Deputy Chief Engineer for the technology demonstration. Ames, therefore, focused on how to improve managing traffic on the ground and scheduling departures.
Ames, which houses the Aviation Systems Division of NASA’s Aeronautics Research Mission Directorate (ARMD), is at the forefront of enabling improvements in aeronautics. The technology demonstration that resulted in IADS, called Airspace Technology Demonstration 2 (ATD-2), was a six-year effort by NASA Aeronautics to build a completely new software that could help improve airports’ data-sharing and traffic movement on the ground, according to Coupe.
ATD-2 technology is already helping airline flight managers oversee plane movement with a commercial software that integrates arrivals, departures, and surface traffic. But managing all activity for all aircraft on the ground requires a sophisticated program.
Just as a traffic officer can prevent gridlock at a busy intersection, IADS is designed to prevent similar traffic tangles. The first test site for the program development was Charlotte Douglas International Airport in North Carolina, the second-busiest airport on the East Coast with only three runways. About 75 percent of those are connecting flights.
Before IADS, one struggle the airport faced was a technology mismatch – the airport’s control tower used one software program and ground management used a different one, with no way to integrate them. A phone call was the most common way to notify each other about changes or problems. With approximately 115 aircraft on the ground at any time, a delay in communication could create complications, according to Davis. A plane leaving the gate before an order to delay was received would mean several planes could end up waiting in line at the runway.
To help NASA create a baseline understanding of airport operations, the Charlotte airport provided blueprints of the runways and buildings, procedures, and any information needed to digitize the process of getting planes and their passengers where they need to go on schedule.
For ramp controllers, managing airplane movements involves hundreds of people and thousands of procedures. American Airlines Inc. operates 700 or more flights out of Charlotte a day, so the Fort Worth, Texas-based company was able to provide NASA a wealth of information about everything from passengers, wait times, and crew schedules to ground services and FAA tower communications.
The test demonstration participants provided input about priorities and then feedback on the new program’s performance, including the end-user display that shared the data.
Departure surface metering tracks and helps coordinate aircraft movement while they’re on the ground. Seeing the exact location of every plane, even when it was in motion, was revolutionary. The visuals made it easier to coordinate the interrelated activities. The resulting benefits were tremendous.
When flights were assigned an order for takeoff – first, second, or third – the airline could hold each plane at the gate longer, only starting engines when it was time to push back. Taxi time was also shorter because the place in line was set. Takeoffs occurred within minutes of leaving the gate.
During the first four years of ATD-2, it’s estimated the airlines at Charlotte Douglas realized a savings of over one million gallons of fuel, almost 11,500 tons of carbon dioxide emissions, and 5,948 hours of engine run time and the related maintenance costs. Savings for flight crew costs were approximately $1,330,000, and the value of passenger time saved was approximately $4,400,000, thanks in part to a 916.4-hour reduction in delays.
For more information visit https://spinoff.nasa.gov/Electronic-Traffic-Monitor-for-Airports .