Curious Conversations, a Research Podcast

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Travis

Earlier this year, there was quite a bit of speculation when lights began to dance across the night sky along the east coast. Some were worried a nefarious actor might have been operating in our airspace, while others were concerned that Hector might have in fact been Alf looking to confiscate neighborhood cats.

While the vast majority of those did turn out to be people just flying drones, it did leave me curious as to what regulations there are when it comes to flying a drone in our airspace, and what kind of countermeasures do we currently have in place to detect and maybe even mitigate possible threats. And thankfully Virginia Tech's Tombo Jones was kind enough to answer all those questions and more.

Tombo is the director of Virginia Tech's Mid-Atlantic Aviation Partnership, where he leads their work as a federal aviation-administrated, designated UAS test site. Tombo and I talked a little about what's required to fly a drone in the United States, as well as what some of the technology is that we have when it comes to detecting and maybe even mitigating against drone threats. He also shared some of the plans that Virginia Tech has to create a new center to help mitigate this threat in terms of national security.

And he shared his insights as to what you and I can be looking for when we start to see lights dance across the sky at night. And of course, don't forget to rate, follow, and or subscribe to the podcast. I'm Travis Williams, and this is Virginia Tech's Curious Conversations.

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Travis

You know, the past few months, I guess, or maybe even longer than that, there's been a lot of buzz about stuff that people have seen in the air. And there's been a lot of speculation, I think, just from the general public about that. So I'm really curious, when you, doing what you do, you see something like that, what is your first thought as to what that is?

Tombo

Yeah, I think it's a great question, Travis. And it's a worthy question for our industry. Well, first of all, my first thought when I see a drone, answer your question directly. When I see a drone flying, it really depends on what the drone's doing. Just because it's flying, I don't necessarily think that it's doing anything wrong. know, the FAA has worked really hard and our industry and the test sites and the organizations, many of which we're a part of, have worked hard to legitimize operations and to bring about the benefits that drones do for good. But...it's true that like any other technology, technology can sometimes be used for bad, right? And so when I see a drone flying though, I don't necessarily think that it's doing something wrong. Oftentimes I think perhaps that's a commercial operator that has the right FAA training to do the flights or maybe it's a recreational operator who also, for a recreational operator nowadays, they also have to have a certification from the FAA where they get trained on the rules and regulations about where to fly and what to do.

The times that I will get concerned is when I see a drone doing something that I know is not allowed under the regulations. And there are some very specific regulations about what drones are allowed to do and what they're not. And so that's when I'll get concerned. But for the most part, when I first see a drone, I think, hey, here's a technology that's out doing a job that oftentimes can be done safer than it can be done in the traditional methods, such as inspecting roofs for health damage.

It can be safer than sending somebody up on roof, such as inspecting a power line for damage. can be safer than flying a helicopter along the power line. And I'm a helicopter pilot by trade. you know, I'm sure all my fellow helicopter pilots think I'm a trader there by saying the drone can do it safer. But the truth is we know that the drone can do it safer. So my first thought is not that it's bad. It's that it's probably up to good unless I see something that's doing it. Like flying over people. So many people don't know that a drone, so when you get your recreational certificate or your commercial certificate, you learn the rules and regulations. And one of the primary rules is you're not allowed to fly a drone over people. And there's a few exceptions, but the safety reason for that is if the drone quits, it could injure someone, right, if it were to fail. And there is a rule that came out a few years ago that outlined how you could fly over people if you could pass certain test methods to show that if the drone were to strike someone, it would not calls a fatality or a significant injury. We actually happen to have one of the only test methods, there are two in the nation, but we have right here at Virginia Tech, something to be proud of, we have one of the only two test methods to test drones for safe operations over people. And that's in a partnership we have with the Center for Injury Biomechanics, which of course, I'm sure you know is famous for their helmet testing. So they have a lot of experience in injury testing and our team that has experience with drones teamed up with their team that has experience in injuries and we...work with the FAA to get that approval. that's just one of the examples of a rule that many folks don't understand or know that the FAA has implemented for safety reasons.

Travis

What if you just see lights flying in the sky? you automatically think it's a drone or are you maybe like maybe maybe this is ET? I don't know.

Tombo

Yeah, I don't think it's ET. I don't think it's a UFO. Although I suppose that's possible. You know, traditionally our skies have been filled with traditional aviation. So what we call now crude aviation, right? What you and I traditionally would have thought just call airplanes and helicopters. Usually that's my first thought. I tend to think it's a drone only when certain I see or hear certain things, right? And they have different lighting schemes usually. So And that's a great way for people who see an aircraft in the sky to try to determine whether it's a traditional aircraft or a drone. First of all, they're both legally allowed to fly at night. Drones are allowed to fly at night. Crewed aircraft are allowed to fly at night, obviously. Crewed aircraft have, there's FAA regulations that are very specific about how they have to be lit. They have to have position lights similar to the way that boats do, sorry, they're called navigation lights. Essentially where you have, green on one side and red on the other so that people can tell the orientation of the aircraft the same way that as I suggested that boats do. You know, they're required to have a white tail light on those aircraft. They're required to have a landing light that is on during certain times. Those other lights have to be on at all times. The landing light has to be on when it's in particular, you know, 10 miles from an airport on the way to an approach as an example. And it'll have strobes on the end of the wings too as a requirement and or what we call anti-bang lights is the slang term, but essentially it's anti-collision lights. So when you see those lights on an aircraft, and they can be positioned slightly different on a helicopter than an airplane, but if you kind of understand the requirements of where those lights have to be and the ones that have to be on all the time, you can sometimes realize that's an airplane instead of a drone or that's helicopter instead of a drone. A drone, what's different is a drone to fly at night is required to have lighting.

But there's not a specification on what the lighting array looks like or where it needs to be positioned. It simply has to have a light on that can be seen from three miles. so drones oftentimes don't have nearly as many of those lights. And frankly, unless we're talking about really large Department of Defense sized drones, the drones that we're talking about just don't have the tight wingspan to put position lights on, for example, that are spread apart by a 12 meters like you might see on a Cessna. They may have green and red lights which make it a little confusing because you can't tell how far away it is. But generally speaking, you might be able to tell the difference in the two between, because the lighting schemes are very different. Another huge cue is noise, right? So drones, they're not all electrically driven. You know, there are certainly drones that are gasoline, that have gasoline engines or other propulsion engines that are more traditional in nature in terms of noise. But a lot of the drones that we see today that are flown and that you hear about in the news that are bought off the shelf, like DJI drones, which are probably the most common in the United States, or Skydio drones, which is another company that sells a lot of drones in the United States. Those type traditional commercial shelf drones are electrically driven, so they sound very different than an aircraft, than a helicopter or an airplane. And so if you can hear the aircraft, you can also oftentimes tell whether whether it's an electrically driven motor or a traditional engine that has that type of deeper roar to it. So I think those are a couple of cues that are pretty helpful. One thing that's kind of a, I'll share this with you, Travis, the New York Times, actually, thanks to your team's help in connecting me up with them, they did a really good article on some of the drone sightings. And we talked about in the interview that I did with them about how if you see an aircraft in the sky and you don't know whether it's a drone or an airplane, a great way to reference that and determine, and it's not foolproof because not all airplanes and drones have this, but something like 75 % of the aircraft flying in the sky, that number changes every year, but have a transponder that's an ADS-B transponder. And you and I can just get on apps like for flight, which is a paid subscription, but there are plenty of free ones like Flightradar24 and plenty of others. And you can, if you, you know, it'll show, for example, you can look and see, okay, I see an aircraft over here to the west. And you bring the app up and it will literally say, there's a helicopter operating 2000 feet above you and two miles to the west. Like you'll see it on there. It's kind of like utilizing your phone for Google maps. And you can see, That's probably that helicopter I'm looking at or, by the way, that's probably that Delta Airlines. And I just don't realize how hot it is. Like, so you can, that's a great method to maybe calm some concerns. If you're trying to figure out if it's a drone you're looking at or an aircraft, and you may be able to quickly determine that indeed it's an aircraft. And that New York Times team, they, they did their due diligence. They took a lot of those drone sightings and the cell phone camera, um, location data and orientation data. And we're able to determine. Indeed, this was a passenger carrying aircraft. Indeed, this was a helicopter. You know, indeed, in most all the cases, at least the ones that they shared with me, that they were able to rule out that they actually were not drones.

Travis

Wow, that is phenomenal. I'm so glad that you got to talk with them and you got to share that with them. And I'm excited to try some of those apps out for myself when I start to see things in the sky. think they will help calm some possible nerves around my house.

Tombo

Yeah, one last thing while we're talking about being able to look at an aircraft and determine signatures through electronic means. I talked about transponder, right, on the traditional aircraft. There's a rule for drones that's called remote ID. And if folks are interested, they can look at it. I will share that the FAA has taken great strides in working to ensure that, you know, when a drone is being operated by somebody, that there is some ownership that or should I say some responsibility that can be captured and for law enforcement to be able to determine who is flying that drone, right? And so the way remote ID works is it requires that all drones that operate and all drones that have manufactured after September of, I think it was 23 and drones that were manufactured before that date have to put their own transponders on. And essentially they're broadcasting a packet of information, know, best way to describe it. It's kind of like license plate information that a law enforcement officer can, has the ability to interrogate that drone with their phone. Because it uses, the transponder uses either Bluetooth or wifi to transmit. And so if they're within close proximity of that drone, that operator, it gives information about the drone in terms of its 3D position in space, but important information it gives is what the registration number of that drone is, and all drones have to be registered.

And so they'll be able to tell who's operating the drone. And it also tells them from what location the operator's flying the drone, which is also super valuable, should law enforcement want to go ask. Because they may have the same questions that I have. It could be a legitimate drone flight, and they may just want to go ask. Or maybe it's a drone that's being flown in a place it shouldn't be, such as over a stadium during a football game. That actually happened at Virginia Tech.

And some of the law enforcement folks who were able to determine and find the person who was flying the drone and who just didn't know any better. Basically, he was flying in video and did not realize he was flying in a TFR, which is a restricted flight, temporary flight restriction, which occurs over games. so, you know, our industry is getting better and smarter and the FAA is leaning hard and trying to educate people, but there's still some folks out there that are operating out of ignorance.

You know, the same way that happens when you and I drive to work every morning. There's some people that aren't very good drivers, right? That don't know the rules and don't follow them.

Travis

I think that I've seen some people maybe operating out of ignorance. may have, I may be guilty of that. We're trying to do better, so yeah.

Tombo

Yeah, I'm sure we all are. That might be a perfect transition to talk a little bit about counter US because that drone that was, told you, was flying over Virginia Tech during one of the football games, that it was a drone detection system that found that drone. And there's been a lot of news recently about drones, obviously flying in the New Jersey area, the New York area, concerns there, even some in Virginia. To be more specific, and this is public knowledge,

There have been drones that have been flown, that have been detected by humans, so like people hearing it, on some of our Eastern Shore NASA bases that were not detected by drone detection systems that were on site there. And there have been drones, obviously, the Tower 22 incident overseas where some soldiers were killed, where a drone was flown in to that base and sadly killed some of our service members. It flew in undetected there have been different instances of drones being used for nefarious reasons. that brings up, you know, I've talked a little bit, a lot about drones for good, but we're also doing work here to try to assist in the counter US space. And the reason we're trying to do that is because Virginia Tech has a mission to work and assist in national security, to work in that realm. And so we partnered with the National Security Institute and we're working on a Department of Defense project to stand up. You know, right now we're an FAA test site. This is to stand us up as a counter UAS test site as well. And so we're going to establish the infrastructure to test and evaluate systems that are designed to detect drones and evaluate the system's ability to determine whether or not the drone is operating legitimately and then what to do about it in terms of mitigations and how it will be mitigated. And so we're pretty excited about being able to work in that realm too, to help with national defense at the Department of Defense level and then also looking to do some work at the federal, other federal agency level and state level. For example, we did some of this work already for the Department of Justice and working on helping them keep contraband out of prisons. And certainly there are a number of critical infrastructure sites that many different entities across our state, I'll just say Virginia, is looking to protect that we're eager to help assist there. So this new counter US site that we're in partnership with National Security Institute. pretty excited to be standing up this coming year.

Travis

And I want to ask you about that. But first, I'm a little curious because we started this conversation talking about all these regulations and all these different things that drones have to do, drone operators have to do, and it made it sound like, well, yeah, it doesn't sound too complicated to detect where they're at and that they are drones, but I know it just can't be that simple. So what are some of the biggest challenges when it comes to detecting these drones?

Tombo

Yeah, absolutely. That's a great question. you know, drones are actually much harder to detect typically because they're smaller and quieter, right? In crude aircraft. As a matter of fact, a lot of our research in trying to keep crude aircraft and drones from hitting each other has been in kind of how easy is it to see a drone to miss it? Drones have to give way to all other aircraft, including balloons, by the way. Well, actually all aircraft have to give way to balloons, but including every other type of aircraft. The drones are the bottom of the totem pole right now.

Travis

So balloons are at the top of the totem pole? Like, hot air balloons?

Tombo

Yeah, so if I fly in a Cessna and I'm part of the Hokie Flying Club and I see a balloon, I have to get away to that balloon. And it's really, if you think about it, at first it seems kind of like, wait, why would the rule be like that? Because is a balloon more important? It's really about maneuverability, right? So a balloon can only move on one axis and that happens to be with the wind, right? I mean, they can go up and down, but they're always moving on one azimuth. And so that's why they're top of the hierarchy in terms of right away.

Travis

Well, I thought that might be because they're the best-looking but that makes a lot of sense.

Tombo

They are beautiful aren't they?

Travis

Yes, I think so, absolutely.

Tombo

Yeah, no doubt. Anyway, we're talking about how difficult it is to detect a drone. So because drones typically tend to be much quieter, they're much smaller. Even if you're following the regulation and have one light on your drone that can be seen from three miles, you know, it's not nearly as lit up as a traditional aircraft would be. And so I think probably the biggest two factors are that they're small and they're quiet. And so that makes them much harder to detect. But there are a lot of ways to detect them. And this goes for all aircraft detection. If you're trying to detect crude aircraft to get out of the way, if you're trying to detect drones in order to determine that there's an aircraft there and then to be able to determine whether it's on a legitimate mission or not, is that you can detect them obviously with the naked eye, which is really hard to do. You can detect them with radars. That's no surprise to anybody. Like I'm sure that while they have a smaller radar cross-section, radars, and there are companies out there that are working really hard at this.

Radars can be tuned to detect the smaller aircraft. Most of the challenges with that sometimes comes with filtering out things like birds. But anyway, radars work well. You can do acoustic detection of drones. So they do produce an acoustic signature, right? And so there are companies that work specifically with acoustic detection, microphone arrays, acoustic software systems that use machine learning, for example, to determine and filter out and determine if there's a drone present. And actually the technology can even be taken further where you could catalog and determine what type of drone it is you're listening to, right? That's really challenging to do, but there's people working on it. Another one is EOIR. That stands for electro-optical infrared, which basically means a camera that can see at day and night. And so there are camera systems that also are working in this space to be able to detect drones. And so those are probably the three most popular. I will tell you that there's one that most people probably don't think of that actually works really well, and it's the spectrum. And what's meant by that is most drones, if they're being operated the way that the manufacturer designed them to be operated, are broadcasting a signal, a communications link back to the person who's flying the drone, right? If it's being manually flown for sure it'll tell the operator where the drone is, that's called telemetry. And then the drone operator is operating, you know, their controls, so like joysticks, and those signals are being sent to the drone, right? So there's a lot of communication going back and forth, right? As well as a camera feed communication signal. So there's a lot of RF spectrum that's being broadcast from a drone. And most commercial self-systems, that's either Wi-Fi or Bluetooth, which is not a secure broadcast signal, but essentially, they are producing typically a, they're broadcasting some type of radio signal. And so that's another way to detect that there's a drone there, right?

Travis

I assume that detecting the drone is one measure of counter-UAS. Once we detect a drone and maybe we decide that this is not a drone that we want to be here, what else can we then do to maybe prevent any other sort of nefarious act?

Tombo

Yeah, so in counter UAS, there's two pieces. There's first the detection piece, which we just talked about. And then there's the mitigation piece. And that mitigation piece is the piece where you have determined that a drone is operating where it shouldn't be, that it's nefarious, and that you mitigate against it. And I'll just share that there are a lot of regulations against this right now. There are lot of regulations that keep just anybody from being able to mitigate. And that's a good thing, right? We've seen a lot of people misdiagnose.

What they think is a drone and it's a commercial airliner. So we don't want people, the wrong people being able to mitigate drones, right? But the second piece is mitigation and that comes in a myriad of different ways. It could be kinetic. And kinetic drone mitigation is really kind of what it sounds like. You're basically interfering physically with the drone. It could be shooting it out of the sky with your traditional, like you might shoot ammunition out of a gun. It could be shooting a net towards the drone. That's also considered kinetic because it interferes with the drone's ability to fly. Or in some way, you are using physics to knock it out of the sky in terms of interfering with an object. You can also take over a drone also with RF spectrum. So there's two things. You can actually mitigate it by flooding it just with high energy spectrum, which causes it not to be able to communicate. And usually what happens there depends on the level of energy directed at it.

Usually what happens is it may lose its link. And so most drones are programmed to then go somewhere. It could lose its GPS signal if you use a GPS jamming device. And then it will also go to wherever it's programmed to go. Actually, it can't go to where it's programmed to go to. It may land in place. It may hold its position. It may even crash if it interferes, you know, runs into another drone in the example of a swarm. But there's interference there. You can also...

If you know which drone it is, which this is really graduate level stuff in counter US, but if you know what drone that you're observing and you want to defeat it, there's something called takeover. So RF takeover is where you actually flood it with the right communications telemetry data so that you're telling it now that you're the actual one that's controlling, right? You're essentially overpowering the person who's controlling it with your higher level energy, proper protocols for the drone to respond to and then you control it. And that's really the safest way to take it over. Cause if you think about it, if a drone is nefariously flying over a stadium and I just knock it out of the sky, I've taken one risk that possibly it was nefarious and was gonna hurt somebody, but I'm also possibly gonna hurt somebody by causing it to crash onto them, right? So.

Travis

That seems like it might cause more problems than it's worth.

Tombo

Yeah, yeah, quite possibly. So RF takeovers another way. Those are the two most common is using RF or kinetic to take over a drone. I mentioned that, you know, there's a lot of regulations around who can do this and I'm glad there is, right? I mentioned why that is. I'll share with you that it's really tightly held right now. And I think that's a good thing until we can get some counter US systems to do a really good job. Because different systems have weaknesses and strengths in different areas. And oftentimes you need a array of systems to be able to provide that umbrella. But to give you an idea, we're talking about the Department of Defense, the Department of Energy, the Department of Homeland Security, and the Department of Interior. Those are the agencies that are allowed to do mitigation work. Right now, your state police can't, your local law enforcement can't, unfortunately, and sometimes they legitimately need that. So I'm hoping we get to a place where we can safely do a better job of determining when a drone needs to be mitigated and when it doesn't and have those resources in the right hands. But I will share with you You know, in a future state, what would be optimal? There's something else the FAA is working on that we've done a lot of research on here at Virginia Tech and we're really proud of because we've been the only test site to work on this. Sorry, the only test site to work on every single FAA program with this. And that is called UAS Traffic Management. And that is basically a NASA construct that was born in NASA and is now in the FAA. That all drones, they share their They share the airspace by communicating through particular software programs where they request and reserve different airspace, both static and dynamic. And what I mean by that is maybe a column of airspace static or maybe dynamic, like I am specifically at this place moving at this speed and just a small bubble around me that's protected, right? So all these drones are sharing not only where they're going to be, but who they are, that they're legit. So between that, which is coming in the future, and remote ID, you know, that rules out it's a great thing. It still needs some improvement in terms of detection range and some of the information that's provided. But those type things will allow counter UAS operators in the future when they see a drone to be able to, you know, determine not necessarily automatically assume the worst. can determine is this drone legitimate? Is it on a legitimate mission? And then by process of elimination determine possibly this isn't a very strong one. We need to pay close attention to it. And it'll be good when we're at that state, we're not quite there yet.

Travis

Yeah, it sounds like in the perfect situation, or maybe a better situation, we would look at drones more like we do automobiles on the road. Where we're able to look at a license plate, this car's registered, they don't seem to be doing anything crazy, they're okay.

Tombo

Yeah, I think that's a really good analogy.

Travis

And I assume with all of what we've just talked about counterwise, we're going to solve all of that with this new center that we're working on.

Tombo

We're going to do our best, that's for sure. No, in all seriousness, I think we have a huge value to add back to the industry in terms of security, both at the local, state, and federal level would be the end state. taking the expertise that the National Security Institute has in Department of Defense work and our expertise that my team has in drone work and partnering those together and working with the Department of Defense offices that we're first working with on this, will really set us up for success to be able to have a center where these counter US systems that are under development can come here and we can really evaluate their strengths and their weaknesses and evaluate their efficacy, how well they work, and then work to pair up different systems strengths and weaknesses so that these critical infrastructure, the resources that we need to protect as a nation, as a state, as a locality can be done so in the most efficient manner and that does so in a way that makes sure that our interest is preserved.

Travis

This testing and research center will have both an indoor clean space and then also an outdoor space. Why is it important to have both of those?

Tombo

Yeah, absolutely. So the indoor space is going to allow us to do a lot of testing around RF spectrum in a protected environment, acoustic evaluation in a protected environment. So as you suggested, a sterile environment, also radar cross sectioning, but as you suggested in a sterile environment. And so we can learn a lot about the counter US systems and also we can catalog a lot of different things about drones that can be utilized by these counter US systems in the indoor lab. And then the outdoor lab will be a place where we're able to take these counter US systems and deploy them the same way that they would be deployed in Washington, DC, the same way they would be deployed overseas and bases that we want to protect our service members at. And that outdoor environment where we would expect them to be able to operate. And then we can fly a fleet of different types of drones and properly evaluate how well they work in that outdoor environment. So it's a validation of the things we learn in the indoor environment and the in-state would be coming out of the outdoor environment, we'd be able to make really strong recommendations on which systems work best, which systems need improvement, and the specific areas in which they can be improved, as well as to provide them information, those companies information for them to improve their product.

Travis

Yeah, that all sounds extremely exciting. I'm excited to just learn more about it and to see what you all do. You know, I learned so much about drones and just talking to you. I didn't realize I was going to also learn anything about hot air balloons.

Tombo

Well, there's a theory that it's just a really big sky out there and there's a ton of space, but the truth is we often realize that we're having to share that airspace. So understanding what everybody's trying to do is an important facet of being an aviator.

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Travis

And thanks to Tombo for talking to us about all things drones. If you or someone you know would make for a great curious conversation, email me at traviskw at vt.edu. I'm Travis Williams, and this has been Virginia Tech's Curious Conversations.

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