What Happens When Air Traffic Control Systems Go Dark?

Recent outages at Newark airport highlighted the challenges facing air traffic controllers. What's the science underpinning air safety?

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

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• 0:31Ira Flatow?

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• 0:49Flora Lichtman?

  Hey, this is Flora Lixman, and you're listening to Science Friday.

• 0:54Flora Lichtman?

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

• 0:59Speaker 03

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

• 1:14Flora Lichtman?

  You've probably read about the recent outages at the air traffic control center that directs takeoff 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

• 2:00Flora Lichtman?

  Beach, Florida. Michael, welcome to Science Friday.

• 2:02Speaker 03

  Thank you, Flora. It's an absolute pleasure to be here.

• 2:05Flora Lichtman?

  Okay, 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?

• 2:16Speaker 03

  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 to cause that to happen.

• 2:36Flora Lichtman?

  Tell me more.

• 2:37Speaker 03

  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. 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.

• 3:18Flora Lichtman?

  Which were?

• 3:19Speaker 03

  Number one, a way of getting your situation 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.

• 3:38Flora Lichtman?

  And they lost both?

• 3:39Speaker 03

  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?

• 3:56Flora Lichtman?

  How unusual is this?

• 3:59Speaker 03

  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.

• 4:23Flora Lichtman?

  And why were there not backups in this case?

• 4:26Speaker 03

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

• 4:48Flora Lichtman?

  There is now a backup line?

• 4:50Speaker 03

  That is correct for it.

• 4:51Flora Lichtman?

  How dangerous is it for radio and radar to go out, you know, for over a minute?

• 4:58Speaker 03

  Fortunately, not only are 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 at their traffic control. Onboard 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 a pilot so they can see other aircraft. That, of course, is not the most optimal way of providing safe and efficient air traffic.

• 5:41Speaker 03

  But it is that final backup that will avoid a collision.

• 5:48Flora Lichtman?

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

• 6:04Speaker 03

  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.

• 6:22Flora Lichtman?

  Transitioning currently, like where are we in that transition?

• 6:26Speaker 03

  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.

• 6:53Flora 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?

• 7:05Speaker 03

  For the air traffic control profession is an extraordinary profession. I can think of nothing that is more rewarding than that.

• 7:15Flora Lichtman?

  It sounds like you liked your job.

• 7:16Speaker 03

  Yes, I did. And part of it is because 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.

• 8:00Speaker 03

  You're one second away from disaster.

• 8:04Flora Lichtman?

  Whew, that sounds stressful. Is that how it felt, though?

• 8:06Speaker 03

  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.

• 8:28Flora Lichtman?

  We asked our listeners what questions they had for you, Michael, and they had some good ones. Let's bring on Reed from La Vida, Colorado. Reed's a pilot. Go ahead.

• 8:36Speaker 04

  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 there, a three-dimensional picture in their mind. Like their brains might be different than the average person on the street.

• 8:55Flora Lichtman?

  Any response for Reed?

• 8:58Speaker 03

  Reed, 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.

• 9:29Flora Lichtman?

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

• 9:37Speaker 03

  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 chip, 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.

• 10:24Flora Lichtman?

  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?

• 10:34Speaker 03

  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.

• 10:54Flora Lichtman?

  When might we see it go down, that shortage go down?

• 10:57Speaker 03

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

• 11:03Flora Lichtman?

  That's a long time, Michael. Three to five years. I fly out of Newark.

• 11:09Speaker 03

  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 staffing is.

• 11:36Flora Lichtman?

  Is AI changing air traffic control?

• 11:39Speaker 03

  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.

• 12:19Flora 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?

• 12:25Speaker 03

  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

• 13:10Speaker 03

  to move from facilities that are fully staffed or overstaffed to other air traffic control facilities that are understaffed or hard to staff.

• 13:22Flora Lichtman?

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

• 13:29Speaker 03

  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.

• 13:45Speaker 00

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• 15:32Flora Lichtman?

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

• 15:37Speaker 03

  That's correct, Laura.

• 15:39Flora Lichtman?

  I can't imagine what that day was like for you. Can you tell us about it?

• 15:45Speaker 03

  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 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 know 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,

• 16:30Speaker 03

  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 to 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.

• 17:07Flora Lichtman?

  That must have been...

• 17:11Flora Lichtman?

  So frightening.

• 17:13Speaker 03

  If there was 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.

• 17:29Flora Lichtman?

  Hmm. How did you get into this line of work?

• 17:33Speaker 03

  When I was in the Marine Corps, I got to know some air traffic controllers.

• 17:39Speaker 03

  And I felt, that sounds like a really cool job.

• 17:45Speaker 03

  So when I got out of the Marine Corps, I attempted to apply. And that time, the FAA was done taking applications.

• 17:53Speaker 03

  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 it's been a great time ever since.

• 18:10Flora Lichtman?

  Do you miss it?

• 18:11Speaker 03

  Flora, I'm still a 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 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.

• 18:45Flora Lichtman?

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

• 18:48Speaker 03

  Thank you, Flora. It's been my pleasure.

• 18:50Flora Lichtman?

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

• 19:05Flora Lichtman?

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

• 19:11Speaker 06

  Shishana Buckstum. Beth Ramey. Danielle Johnson. Jackie Hirschfeld.

• 19:16Flora Lichtman?

  I'm Flora Lichtman. Thanks for listening.