What Happens When Air Traffic Control Systems Go Dark?

FLORA LICHTMAN: Hey, this is Flora Lichtman, and you’re listening to Science Friday.

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Today on the show, inside the air traffic control tower when things go wrong.

MICHAEL MCCORMICK: Anthony Bourdain wrote that being a chef is a lot like being an air traffic controller. You’re one second away from disaster.

FLORA LICHTMAN: You’ve probably read about the recent outages at the air traffic control center that directs take-off and landing for Newark Airport. At the end of April, radar went black for over a minute. And then a week and a half later, it went down again briefly. And Newark has cut back on flights in and out. Maybe your flights have been canceled or delayed as a result.

So it made us wonder, how does our air traffic control system work? How do air traffic controllers keep track of the planes in the skies, and what is happening when those systems fail? Here to field those questions and dive into the science of air traffic control is Dr. Michael McCormick, who worked as an air traffic controller for 10 years and was a vice president within the Federal Aviation Administration. He’s an associate professor at Embry-Riddle Aeronautical University based in Daytona Beach, Florida. Michael, welcome to Science Friday.

MICHAEL MCCORMICK: Thank you, Flora. It’s an absolute pleasure to be here.

FLORA LICHTMAN: OK, as a former air traffic controller who used to work in the New York airspace, when this news broke about the outages at Newark, what was your response?

MICHAEL MCCORMICK: Initially, as I heard about the outages, I knew about the fact that the approach control services moved from Long Island to Philadelphia. So I immediately thought something happened in that link that caused that to happen.

FLORA LICHTMAN: Tell me more.

MICHAEL MCCORMICK: The approach control services for all the New York metropolitan airports are handled by a facility on Long Island called the New York TRACON. Last summer, due to staffing issues at the New York TRACON, they moved a portion of that approach control from Long Island to Philadelphia, and then they had to link up the equipment to provide the radar and radio at Philadelphia for the Newark airspace.

It immediately struck me that the air traffic controllers at Philadelphia providing the approach control service lost two of their most important tools in order to be able to provide safe and efficient air traffic control.

FLORA LICHTMAN: Which were?

MICHAEL MCCORMICK: Number one, a way of getting your situational awareness. And in this case, that would be radar. The second piece is communication. An air traffic controller cannot carry out their operational plan without the ability to communicate back and forth with the aircraft.

FLORA LICHTMAN: And they lost both.

MICHAEL MCCORMICK: And they lost both simultaneously. So that put the controllers at Philadelphia in the unenviable position of having to come up with, how do I restore this service, what backups do I have, and who do I need to connect with to make this happen?

FLORA LICHTMAN: How unusual is this?

MICHAEL MCCORMICK: This is very unusual to lose both radar and radio. There are equipment outages that occur throughout the air traffic control system. Even though it’s built to be 99.9% reliable, it relies upon a system of redundancy so that when outages do occur, there are backups that can be switched over to in order to provide that service.

FLORA LICHTMAN: And why were there not backups in this case?

MICHAEL MCCORMICK: In this case, it was what’s known as being single-threaded. And that is a single telecommunication line from Long Island to Philadelphia failed. And it didn’t have a redundant telecommunication line to provide a backup to it. That since has been resolved.

FLORA LICHTMAN: There is now a backup line?

MICHAEL MCCORMICK: That is correct, Flora.

FLORA LICHTMAN: How dangerous is it for radio and radar to go out for over a minute?

MICHAEL MCCORMICK: Fortunately, not only air traffic controllers are trained to be able to work around and come up with backups. Pilots are also trained in how to operate when there’s loss of communication or a loss of radar and air traffic control. On board each aircraft, there is a system known as traffic alert and collision avoidance system.

And this essentially, in the cockpit, looks out into the airspace to all the other aircraft and will provide alerts to the pilot so they can see other aircraft. That, of course, is not the most optimal way of providing safe and efficient air traffic. But it is that final backup that will avoid a collision.

FLORA LICHTMAN: So I want to understand this technology better. I feel surprised that radar is still how air traffic controllers know where planes are, given that my phone knows where I am down to 15 feet, obviously, using GPS. So why radar?

MICHAEL MCCORMICK: Radar has been the backbone of air traffic control surveillance since World War II. However, the Federal Aviation Administration is transitioning from that ground-based radar system to a space-based air traffic control system, similar to what you would have on your phone.

FLORA LICHTMAN: Transitioning currently? Where are we in that transition?

MICHAEL MCCORMICK: That transition has actually taken place. So now that surveillance capability is provided through satellites to the air traffic control automation system. At the same time, it’s also receiving the radar. And the reason why that is is because not every aircraft in the United States, especially the small, privately-owned general aviation aircraft, are equipped to transition to a space-based system.

FLORA LICHTMAN: I’m very curious about the job of an air traffic controller. How automated is the system, and how much is really up to the air traffic controller to make decisions about what planes do?

MICHAEL MCCORMICK: Flora, the air traffic control profession is an extraordinary profession. I can think of nothing that is more rewarding than that.

FLORA LICHTMAN: It sounds like you liked your job.

MICHAEL MCCORMICK: Yes, I did. And part of it is because of the constant challenges that you have to go through in terms of making instantaneous decisions. So technology plays a big role in that. It is an important aid to an air traffic controller that enables a controller to handle higher volumes of traffic.

However, it still relies heavily upon the air traffic controller as an individual to be able to maintain that situational awareness, develop that plan of action, implement it, and then constantly update it. That cannot and hasn’t been replaced by automation.

Anthony Bourdain wrote that being a chef is a lot like being an air traffic controller. You’re one second away from disaster.

FLORA LICHTMAN: Whew. That sounds stressful. Is that how it felt, though?

MICHAEL MCCORMICK: No, that is not how it felt. If you do the profession, you do the job because you like it. That is part of what you enjoy. If you do it strictly for the pay, then you’ll start to feel that stress of making those instantaneous decisions.

FLORA LICHTMAN: We asked our listeners what questions they had for you, Michael, and they had some good ones. Let’s bring on Reid from La Veta, Colorado. Reid’s a pilot. Go ahead.

REID: Yeah, Michael, I’m just wondering if air traffic controllers, if they have to have something special about their brain that they’re able to keep everything straight– 10 planes flying in the air, a three-dimensional picture in their mind, like their brains might be different than the average person on the street.

FLORA LICHTMAN: Any response for Reid?

MICHAEL MCCORMICK: Reid, that is a great question. And that is an aptitude that all air traffic controllers are tested on. And then, through training and experience, you’re able to expand that aptitude. Essentially, you build a mental model, and you project that mental model into the future. And you use that new three-dimensional picture that you projected to make a determination on what needs to happen in terms of your plan of action.

FLORA LICHTMAN: Michael, are you keeping it all in your head? Do you write things down? I mean, do you have tricks for staying focused?

MICHAEL MCCORMICK: Whenever you sit down at a radar display or stand up in air traffic control tower, you make sure everything is set up exactly the way you want it to be. So if you’re in a control tower, you’re going to make sure that the shades are drawn right to the perfect level for you. You’re going to know exactly where your pens are so if you need to write something down on a flight progress strip, you can do that.

If you’re sitting at a radar display, you make sure your chair is perfectly positioned. So that then frees up your cognitive resources so you can develop and maintain that picture. And that allows you to have the focus on what you’re doing and not have to worry about all the small things around you.

FLORA LICHTMAN: Hm. We know part of the challenge that we’re facing is a staffing shortage. Why is it so hard to find new air traffic controllers?

MICHAEL MCCORMICK: Flora, it’s not hard to find new air traffic controllers. The challenge is training them. It takes anywhere from one to five years in order to train and certify as an air traffic controller. So there are more applicants every year for the vacant air traffic control positions than the FAA can actually hire and train.

FLORA LICHTMAN: When might we see it go down, that shortage go down?

MICHAEL MCCORMICK: Flora, I expect to see that in three to five years, we will no longer have the air traffic control shortage.

FLORA LICHTMAN: That’s a long time, Michael. Three to five years? I fly out of Newark.

MICHAEL MCCORMICK: So, Flora, that is a long time. And I can understand why you would be a little concerned about that. The FAA has protocols in place that whenever there happens to be any type of short-staffing, either in an individual airport or an individual radar control facility, that they can move the flow of aircraft around so they can balance out that workload with whatever the staffing is.

FLORA LICHTMAN: Is AI changing air traffic control?

MICHAEL MCCORMICK: AI is not changing air traffic control today, but is currently being developed to provide an assist tool to air traffic controllers, something known as a decision support tool, in that AI will be able to look at the entire trajectory of all the aircraft in the airspace at any one time– and there’s usually about 5,000 to 7,000 aircraft in the air traffic control system at any given time– and be able to predict when there could be or will be a possible conflict between two trajectories and provide that information to the controller. So the controller could then make the decision to change a flight path, change an altitude.

FLORA LICHTMAN: In your opinion, Michael, what do we need to do, what does the federal government need to do to shore up air traffic control?

MICHAEL MCCORMICK: Flora, I believe that the US government can do two things. One, ensure a reliable, consistent funding to the air traffic control system. Every time there is a government shutdown for one week, one day, or one month, that means during that time, everything stops. There’s no work on any new systems, and there’s no hiring and training of air traffic controllers.

So over time, whenever this happens, it causes a problem for the FAA. The second thing is, of course, air traffic control staffing. And that is providing the funding and the ability for the FAA to provide incentives for controllers to move from facilities that are fully staffed or overstaffed to other air traffic control facilities that are understaffed or hard to staff.

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FLORA LICHTMAN: Don’t go away. After the break, Mike tells us about his decision to shut down the NYC airspace during 9/11.

MICHAEL MCCORMICK: If there was any one emotion that I felt, it was more anger that somebody would use something that I just love, and that’s aviation, as a weapon against our country.

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FLORA LICHTMAN: You were in control of the New York City airspace on 9/11, I understand.

MICHAEL MCCORMICK: That’s correct, Flora.

FLORA LICHTMAN: I can’t imagine what that day was like for you. Can you tell us about it?

MICHAEL MCCORMICK: September 11, 2001, was both personally and professionally impactful to me. One, the previous weekend, we had spent the long weekend in Manhattan, and it was my younger son’s first visit to the World Trade Center. Then come Tuesday, September 11, being notified at 8:40 in the morning there’s a possible hijack over New York and heading southbound, that is a unique experience.

And then to go out and that it was, in fact, a real hijack from the flight crew and the cabin crew, and then to watch that target as it went southbound toward New York City– and I was actually on the phone with the Newark air traffic control tower, and I had informed them to look up the Hudson River. There might be a 767 attempting to land at your airport. And that’s when they said it just hit the World Trade Center.

At the exact moment they said that, a controller behind me said, I have another one. And that was United 175 turned 180 degrees and headed back toward New York City. Actually, I knew after the first aircraft at the World Trade Center, we were under attack. And I knew the only way that I could prevent any additional attacks was to remove the weapon of choice, which was aircraft. And that’s why I made the decision to shut down all the New York airspace.

FLORA LICHTMAN: That must have been so frightening.

MICHAEL MCCORMICK: If there is any one emotion that I felt, it certainly wasn’t fear. It was more anger, anger that somebody would use something that I just love, and that’s aviation, as a weapon against our country.

FLORA LICHTMAN: Mm. How did you get into this line of work?

MICHAEL MCCORMICK: When I was in the Marine Corps, I got to know some air traffic controllers. And I thought, that sounds like a really cool job.

So when I got out of the Marine Corps, I attempted to apply. At that time, the FAA was not taking applications. But then, the following year, the air traffic control strike happened. So the day of the air traffic control strike, I put in my application, and I was fortunate enough to get selected. And then it’s been a great time ever since.

FLORA LICHTMAN: Do you miss it?

MICHAEL MCCORMICK: Flora, I’m still part of it. So I teach air traffic management. I train the air traffic controllers of the future. So I get to see them every day. I get to work in a simulated air traffic control environments, both tower and in radar.

And I work very closely with the FAA in a program where my students can be directly placed in air traffic control facilities. So I still consider myself a part of it, even though I’m not actively controlling airplanes. But yes, I would love to do that.

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FLORA LICHTMAN: Thank you for doing what you do, and thank you for talking to us today.

MICHAEL MCCORMICK: Thank you, Flora. It’s been my pleasure.

FLORA LICHTMAN: Dr. Michael McCormick worked as an air traffic controller for 10 years and was a vice president within the FAA. He’s an associate professor at Embry-Riddle Aeronautical University based in Daytona Beach, Florida.

And that is about all we have time for. Lots of folks helped make this show happen, including–

SHOSHANNAH BUXBAUM: –Shoshannah Buxbaum–

BETH RAMME: –Beth Ramme–

DANIELLE JOHNSON: –Danielle Johnson–

JACI HIRSCHFELD: –Jaci Hirschfeld.

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