Air Traffic Control Technology

up in the air on this one. Yeah, but fortunately a listener managed to uh to to get us on target targets. So let's go to a little listener mail. This listener mail comes from Paul, and Paul says, Hi, John and Chris, I enjoy your podcasts and those of your associates and How stuff Works very much. I thought this might make an intra sting topic, the technology behind

air traffic control. I was told that at one time, and perhaps this is still true, that the US is using very old computer technology for air traffic control and that plans to upgrade the system have been bogged down for decades. But appreciate your insight into this. Thank you. So much for keeping me entertained over long hours in my car. Paul. Alright, Paul, Well, we're gonna talk a little bit about air traffic control and what goes into keeping everybody safe up in the skies and uh, well,

to talk about the old technologies. It's true that a lot of the technology used in air traffic control has been around for for a while. Um, there are plans to eventually automate the system, but that still not here yet. Yeah. Yeah, I don't know why he'd be concerned about that. I mean, it's not like fifty thou planes are in the air every day over the United States. Wait, oh wait, yes they are on a good day. Um. Yeah. The the automated thing, well, I'll go ahead and get this all

the way first. One of the there's several reasons why it would take a while to move to a fully automated system. One is that while you're upgrading to the fully automated system, the existing system would have to continue to operate. Because it's not like we can just say, you know what, we're gonna take a i don't know six months and not fly all right, you guys look out for yourselves out there. Well yeah, we're gonna paint all the planes a bright day glow pink or green

and uh and yeah, good best of luck. Now that that's not the way it's gonna that's not the way it can work. So obviously, if you're going to to upgrade a system as huge as the air traffic control system is, and we'll get into how big it is in a minute, um, then it's gonna take a lot of time, and you're gonna have to you're gonna have to duplicate systems uh while you are ready getting ready

to switch over to the other side. And then if there's an element that requires airplanes to also get upgrade, it's that's an entirely different issue because now you're talking about two totally different multiple systems really, because you've got the government system, which would be the air traffic control because that's overseen by the f A A, right, so

that's a government agency. And then you have all the private companies that are the you know, the private airlines, not to mention private pilots and uh, and you know, to upgrade their equipment. That also is going to take a really long time. So it's it's one of those where the the the job is very complex, it's huge, and it's the government. I think if you talk about huge complex and government, you you realize that means lots

of time is going to go by before it ever happens. Yeah. Yeah, but that's not because you know, people just don't want to do it. It's it's complex, so right, and it's expensive, it's you know, and again this money comes from taxes. Turns out people aren't thrilled about paying taxes, so anything that requires tax money it ends up being a clitical battle. So I mean, the complex, like we said, goes well

beyond just the technology. But now that we've covered that, let's talk a little bit about what is involved in the air traffic control system. As a matter of fact, speaking of complex, the air air traffic control system itself is very complex and this probably will give you a better idea too, in the types of technology we're talking about.

Um As it turns out the h the air traffic control space is divided up really in three dimensions, which is appropriate, but it's kind of it's kind of weird to think about when you're not I guess, when you're not thinking about how air traffic control works on a data right basis, because um the United States is divided up geographically into twenty one different zones also known as centers,

and each of those zones is divided into sectors. While those are two dimensions, uh you know, the with the United States and the length, and then you have the altitudes in those zones, and they're are different groups of people who are managing aircraft as they move from one zone to the next. Um So, which is kind of weird to think, like I said, and it's kind of weird to think about it because you're thinking, Okay, well I got it. You know, you're flying from say, Dallas

to Chicago. You know, you say in Dallas, hey I'm going to Chicago, and Chicago says, okay, well come on, we're ready for you. That's not really that simple, right, it's you know, from from a passenger experience, what it seems like to us is that you have when I don't know about you, Chris, but when I think air traffic control, I'm thinking of the towers at the airport, right, So you're the only part of it, yeah, exactly. But you're at the airport, you see the air traffic control tower.

You know that the pilot is talking to air traffic control and saying, hey, I got a bunch of people here. They want to get off the ground, and air traffic control is like, well, we're gonna make them wait around a while because we're jerks. And then the pilot says, but we're the ones who get all the blame, and the air traffic control says ha ha ha, And then

actually that's probably not how it works. But at any rate, the pilot contacts air traffic control, they get the clearance to take off, and then you're in flight, and then you you pretty much don't really think about air traffic control as a passenger until you get close to landing. So you're thinking of the starting point in the endpoint, uh as like the air traffic air traffic control tower

in both airports. Turns out there actually several stations along the way that UM monitor your flight for the entire duration of the flight. UM. Now, the the tower that you're talking about, Jonathan, is the air traffic control tower a t c T. And that's you can find one of those that basically any airport that has regularly scheduled flights and they you know, managed to take off and landing in the ground traffic to make sure that they know what's going on. But once the plane well, okay,

we'll talk about the other parts. Um. The other parts are the Air Traffic Control System Command Center a t C s c C, and that's uh basically that's in charge of all air traffic can roll UM you know we're talking about. They manage things, you know, routing traffic and bad weather and and trying to figure out what's going on with the UH UM traffic patterns and how the runways are dealing with on the ground. But um, locally you have Air Route Traffic Control Centers a r

t c C s UM. Each center has its own r t c C and they manage traffic within the sectors UH in that area except for the next group the tray con terminal Radar Approach Control and they handle the departing and approaching aircraft within that space that they are assigned. And that space is around fifteen miles and radius. So UM. Yeah, So what we're doing is we're going from very large and getting progressively smaller here, right. Yeah. So we've got the center, which is the big one.

You've got the you know, the air Route Traffic Control Centers which that controls a zone or that's what we you know, the center slash zone, however you want to call it. So there are multiple sectors within that. Then you've got the tray con, which can actually overlap sectors depending on where it is geographically. But um, it's got the fifty mile radius. And then what's next after that? Um? Wait,

after the traycon? Yeah, I guess the tracon is technically the air traffic control tower because at that point you're dealing with the airspace around the airport itself. And then there's you know, the flight service station. So if you need information about whether or the route or flight plan for private pilots, um, then you would consult with the flight service station. But those are in smaller, smaller areas, and there are people like rural rural airports I'm sorry, yes, um.

And you know, in the case of emergencies and uh, you know, if there are search and rescue operations that need to be managed for a missing or overdo aircraft, the flight service station us involved with that. But um, yeah, I mean small small aircraft that are lying by vision only visual flight rules. Um. You know, they don't really they're not required by the f A to file a flight plan. Um. So the mainstream traffic control centers don't

deal with these smaller aircraft, right. They they have specific rules they have to follow which prevent them from getting within the same sort of flight space as the massive larger aircraft. But as long as they are following the rules, than they don't have to to do a flight plan. They don't have to check in as often as the commercial flights do. Um. The ones that are the big boys,

like the commercial flights, Uh, they do. They follow the instrument flight rules, right, which means they can fly in all kinds of weather because they're they're using instruments to guide them. Uh. Not just it's not just you know, oh I can I I have good uh visibility. Yeah, it's like I could see where I'm going going right, that's part of it, right. Um And uh all I f R flight rule pilots, Um, that was redundant. Thanks um My file a flight plan within thirty minutes of

pushing back from the gate. Basically, what you don't see the pilot doing is checking the weather, making sure that

the route is okay, and filing a flight plan. And that's got all the information in it that the air traffic control folks are gonna need to know like the name, flight number of the air the airline, the type of aircraft they're flying in, the equipment on board, the intended air speed and cruising altitude, and the route of the flight right and this is of course, all this information is necessary for air traffic control to make sure that there are aren't any uh there's not gonna be any

real congestion in the flight space about the United States, not that kind of congestion, but to make sure that you're not gonna have any potentially dangerous situations due to too many aircraft occupying the same space at approximately the same time. So that's why all these flight plans have to be filed. It's uh, it's really to give air traffic control the the big picture look at what is going on at any given time above the United States airspace.

Should I go on? Please do? In the tower, We've got a flight data person who's checking the weather and flight plane information, um and then put it into the f a a host computer and UM the computer comes up with a flight progress strip that goes from the controllers to you know, to the flight from different station

to station. Uh. So that it's possible to track a particular plane, right, So as a plane travels from one zone into another, the controllers for those zones have to be able to pass the information along to the next controller so that everything remains up to date and everyone knows where everybody is. Uh. So it turns out that's important, right.

So for for a flight from one coast to the other, you will cross through several zones, so many different controllers will have their hands on that on your flight's information as you go from one side to the other. So let's say like Atlanta to l A. I'll be taking

that flight in June. So as I'm taking that flight, you're I'm going to you know that that flight's information is going to pass through not just the local air traffic control uh team that's that's there at the Atlanta Airport, but through many different centers as we fly across the country.

That's right. Um, I mean the ground controller is managing the ground traffic, the traffic you know what's going on on the literally on the ground where all the different planes are with regard to the runways and taxi ways. Um and um. You know the local controller is in the tower as well, watching the sky around met the immediate area around the airport. Yeah. And as for what kind of technology, these guys are using binoculars also radar

and so, you know, pretty dated stuff, but it works, right. Yeah, it's it's one of those things now. Great, if visibility is limited, they're going to be relying more in the radar than the binoculars. Uh. And if it gets too limited, that's when air traffic control says, you know what, the conditions are too dangerous for flights to take off and land out of this airspace, and so we are going to delay any flights, uh for the you know, for as long as the weather remains this bad as or

as of the day that we're actually recording this. This guys are full of volcanic ash, right, So if you are in the UK and you want to fly someplace and you realize that, you know, or the eight air Traffic Control realizes that the air is completely filled with ash and it's really impacting visibility, you might be grounded. Yeah, it's funny. Just as an aside that I was listening to a report on that this morning and they said, yes, you know, there are bits of glass in the air

thrown up there by the volcano. So yes, as it turns out, flying through that is not very healthy, all right, Uh, aside from a volcano story, yes, we've got um, we've got the local controllers basically keeping an eye on things. UM. And they're basically the ones giving clearance to the aircraft for it to take off. UM. And as the as the plane leaves the ground, the local controller is going to hand off the plane, if you will, to the

departure controller at the tray con facility. UM. It's still going to keep an eye on it within five miles from the airport, but the pilot is now in communication with the departure controller rather than the tower on the ground with whom he or she was just speaking. And uh. Actually, also as the plane is taking off, here's another piece

of technology for you, the transponder aboard the aircraft. The pilots are are you know, engaging that and um, it is identifying radar signals coming in and broadcasting radio a signal of its own in the direction of the radar waves that are coming to it. So it's locked on to the radar and is saying, hey, here, I am here, this is who I am, right, I am so transponder. When you when you beam the radar signal at the plane, the plane says, hey, there's a I've detected the radar signal.

It's from this direction. I am going to identify who I am where I am and uh. It actually has an amplifier as well, so it can amplify that signal send it back to the radar facility. And then that's how the ground can keep track of where planes are as they're in the air. And as it turns out, aircraft are equipped with radar detectors, although they very infrequently get pulled over. Okay, then so the departure controller just getting stared at the departure controller is is working at

the track on facility. Um and uh. You know, the track on facility may actually be in charge of several airports. We're not just talking a single airport because you know, like we said, fifty mile radius, that's a big radius. And if you know, if you're in a there, I can think of like two airports in the Atlanta area right off the top of my head that would fall into that depending on where the traycon U was stationed.

That's right, um and uh. And here again we're talking in three dimensions, So not only as the departure controller looking for you geographically, he also wants to know what the distance is uh vertically, to identify how the distance between any ascending and descending aircraft um, because that is again important to know. And they have specific ascent corridors in various geographic regions. If you've ever taken off from there's certain airports where you have a very steep ascent corridor,

that's true. I've where it's usually because of noise ordinances. And then there's the geographical well there's also yes, there's some that are geographic as well. But the mountain here you need to pull up right, yeah exactly, But there there are several where the the local area has a noise ordinance where the in order to to obey that ordinance, aircraft have to take off at a much steeper incline than normal. And if you've ever experienced this, it's kind

of fun. None if I mean, I enjoy flying, so for me, it's for those who are afraid of flying the enjoy so much so. Um. Then the plane leaves a trayon air space and enters a sector of the A R T C C airspace where at least two air traffic controllers are keeping an eye on the plane.

The radar associate controller is looking UM basically correlating the flight plane information UM to what's going on, and the associate controller is working with the radar controller in charge of that sector UM basically that that person is in charge of all the air to ground communication and trying to make sure that planes are located in a reasonable

enough distance apart that they are operating safely. Right. And you know, these controllers could be monitoring dozens and dozens of planes at any given time because it's they're the ones in charge of monitoring it over their particular center. And as we said, you know there's just twenty one of these across the United States. That means that these are really big areas. So these guys are are men

and women. I shouldn't just say guys. Uh, they're keeping eyes on on lots of different data all going on at the same time. And again we've got like some computers that are uh collating all this so that you can look at a computer screen and see a data

representation of what's going on. But a lot of this is still going with with humans monitoring tools directly like the radar and UM basically the radar handoff controller is helping out too with the radar and associate radar controllers in situations where there's lots of traffic just to make sure that that everything is is going okay, they got

another set of eyes on the situation. And as you go from zone to zone, they hand you off, you know, as you leave one space basically the next as as part of the air traffic control system as a whole, you pass over into the next space and then another

set of controllers helps you out right. And the data from your flight is actually passed on ahead of your flight, so it's not like you suddenly appear in someone's center and then your data shows up and then they say, oh crap, how do we fit them into what's going on?

Like occasionally aircraft have trouble or there's a or someone makes a mistake and UM and the air traffic controllers have to react to that and tell pilots to to change their flight plan and uh, you know, especially like if they if the weather at the destination starts to get really bad and it was not expected and they

have to divert the flight. Uh, you know, you want to catch the stuff as early as you possibly can, and so um uh in order as part of that, as the air air craft is getting closer to the border of one center, uh, they'll go ahead and pass that data on to the next center ahead of time, sometimes up to a half hour ahead of time. And then the that way everyone knows where everybody is before

it becomes a problem. Uh. But yeah, then that the pilot will then be communicating with a new radio controller and uh a radar control or rather not radio And this continues until you get close to your destination. And then it basically happens in reverse. Right you you start communicating with the tower who can relay the conditions on the ground, let you know what's going on as far as traffic is concerned. Yeah, essentially it would be you go.

You would start talking to tracon first, Yes, you would. Tracon would would start to to guide the planes in so that they are coming in at the proper angle for the landing strip. Um. And actually, if you've ever seen there's certain movies that show this. I'm thinking of Pushing ten in particular. But the air traffic controllers at tray Con and the ones at your destination work together to uh to get these planes to line up so that they can land in an efficient and yet safe manner.

So you actually can see if you're looking at the radar that all these flights that are coming from various directions, I mean, like anywhere that you can imagine, you know, they're they're coming in, are all lining up like in a straight line. Um, this requires a lot of coordination. Yeah, yeah, it really does. And it's um A pardon my earlier oversimplification of the landing process. I just didn't want to

get that email. No, yeah, I understand, and you and you're right, Um, but yeah, I mean it's it's funny because the probably the biggest piece of technology in the air traffic controller world is the air traffic controllers. The human technology involved with it. Yeah, I mean we have the radar and and other computer information. But uh, that seems like what we were talking earlier about automating the process. I'm not sure that you know, the human can we

can completely automate that process. It seems like people are a little too necessary. But uh, in general it seems to work. Yeah, if we were to really break it down, the actual computer system has lots and lots and lots of different little components, each of which handles a very specific set of tasks. But it gets so granular at that point that it it's almost it's really difficult to talk about because uh, you know, you're you you have to break it down into such tiny, little little uh segments.

It's hard to get the big picture at that point. It's so to call it a computer system in a way is an oversimplification because there's so much stuff going on. I mean, you're talking about different alert systems and different uh you know, uh, organizational systems. But but we would go insane if we tried to break it down into every little tiny piece. So uh but yeah, and will we ever see it automated? I think we probably will eventually.

But again, this is one of those things where it's it's not just a technology thing, it's a political thing. And uh and you know it's not it's not super high up on our priorities list right now. Well, considering the system is in general working, Yeah, Now, granted, if we wanted to add a lot of capacity to that system, then we would have to really start looking into upgrading it because uh, you know, air traffic control, uh jobs are are fairly stressful, Yes, one of those. I mean,

you think about it. You're in charge of the safety of thousands of people every single day you go to work. So, um, you don't want to make a mistake. Yeah, you don't want to make their jobs more difficult. But um, but yeah, it's it's I'm glad we uh we've had a conversation about that was fun. Yeah all right, Well, if any of you guys have some fun conversation topics he wants to tackle, you should email us. Our email address is

tech Stuff at how stuff works dot com. You can emails kind of like this next example of listener mail. This listener mail comes from Johnny, and Johnny says, here's a funny pun. I found people who plug their computer keyboards into Hi Fi systems aren't idiots. That would be stereotyping. Also, on your microwave podcast, do all the waves get reflected or do some escape? My mom says I should stand five feet away from the microwave when it's on. Is

this necessary? Um? First of all, well, Johnny always obey your mother. Yeah, Johnny's mom, I I have I have expressly told him to obey you. Um, but I think it probably stems from an earlier incident you're not telling us about. Well, my name is also Onathan, and I'm i am Southern, so I'm a mama's boy. But no, the to get to your question about microwaves and whether or not any escape, Uh, well, first of all, microwaves aren't really There are microwaves that are out and about already, yes,

not just not just coming from the microwave oven. But the mesh that's on the door of the microwave is because the microwaves are so big they can't pass through that mesh. The mesh is gonna reflect them right back. Um. So really, the whole fear of radiation leaking out is a little overblown. Now, granted, if your microwave was somehow damaged, then yes, microwaves might be able to escape the the door,

but in which the microwave anymore. No, But even then, as as the founder the the guy who invented the microwave oven could tell you, um, it's not necessarily gonna cause you irreparable harm immediately. It might mal your chocolate bar. That's true. As we discussed in an earlier podcast, the person who discovered the microwave was figured it out because he was standing next to a device that was admitting

microwaves and his candy bar moult. It was a radar te radar antenna and that was where you know he was doing start radar. I feel like I've heard that exactly. Um, you must have been watching mash So thanks a lot, Johnny. I hope you guys enjoyed this show. Also, we have some cool announcements to make. Indeed, one is that if you are on Facebook and you like tex stuff, now you can like tex stuff while you are on Facebook

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