There is growing evidence that non-state actors are incorporating drone technology into their unconventional tactics, prompting concerns from militaries on how they can effectively counter this emerging threat. The Cipher Brief spoke with Michael Balazs and Jonathan Rotner, who conducted MITRE’s counter-UAS challenge with the goal of finding non-kinetic interdiction solutions that could be used in urban environments of future insurgencies.
The Cipher Brief: What are some challenges coming from the proliferation of small, commercially available, remotely controlled aircraft?
Michael Balazs: With any technology, there are ten thousand good ways for every inappropriate way to use it. But, there are a number of things to be concerned about in terms of nefarious actors, because all of those positive uses can be easily turned into negative uses—like the recent incident involving a small drone rigged with explosives that killed Kurdish soldiers. We are trying to look at the whole spectrum—how to stop the misinformed, criminals, and those who intend harm.
Jonathan Rotner: That said, this technology is not at the point where it is easy to just buy and use it for harm by tomorrow. It takes a certain amount of training, familiarity, and investment to turn down that nefarious path. By understanding the patterns of technology development, you can anticipate which kind of capabilities could come down the pipe next.
TCB: Could you explain MITRE’s Counter-Unmanned Aerial Systems (UAS) Challenge?
JR: The challenge was a reaction to seeing a couple of events in the news that were troubling, for example, the drones that landed on the White House lawn or in front of German Chancellor Angela Merkel. MITRE wanted to use a challenge model, because it brings industry toward a targeted outcome, and we could independently verify the technology as an objective analyst, as Federally Funded Research Development Centers (FFRDCs) are chartered to do, without a commercial stake in the game.
The goal was to find appropriate solutions for small UAS in populated areas, meaning you cannot just jam GPS signals as a lot of critical systems rely on GPS—for example, ATMs for timing signals, cell phone towers for geolocation services, and every major bank financial transaction is time-stamped with a GPS signal as well.
We had 42 groups submit from six different countries and invited eight finalists to Quantico for two weeks to test in a real world environment. We had a really good range of technologies that showed up—different sensor modalities and interdiction methods from nets, cyber, and jamming to cameras, radio frequency detection, and acoustics.
TCB: What are some of the promising counter-UAS technologies being considered?
JR: Each has its pros and cons. There is no one modality that is going to be able to stop all the different kinds of threats. Instead you have to start layering different defenses. There is also no environment that you are defending that is perfectly representational of all other environments. For example, if you are trying to prevent stray drones from flying near an airport, each airport is just fundamentally different in its location—some are deep in the city, in which you have line-of-sight issues, or issues of radio frequencies bouncing off of metal walls. So the two lessons learned are that there is no technical silver bullet, and there is no single environmental representation. Each time you have to make trade offs.
MB: There are three broad categories in terms of the interdiction technologies—physical, radio frequency, and cyber. Let’s start on the cyber side because it opens up the most possibilities. If you can breach the command and control stream, you can send all kinds of commands, take control, tell it to ignore the primary controller, send new way-points, or tell it to land. You can even get root-level access to the flight controller.
But to breach a drone’s system, you have to be able to reverse the protocol stream and break its encryption. If a malicious actor simply does two things—update to the latest firmware and change the default password—it is enough to basically defeat most cyber capabilities. So while cyber offers incredible options if you can get in, it is the hardest to do—especially because you generally have a very short response time from an incoming drone.
You also have radio frequency jammers or even GPS jamming. Radio frequency interdiction is all about breaking the command and control communications. You can use blanket white noise spread-spectrum jamming or more selective methods like cogitative jamming, which is listening to the packets coming through the air and jamming critical portions of it.
If a pilot is controlling the drone remotely, the default behavior after breaking that command and control link is for the drone to fly home. But if the system is flying via automated way-point navigation, and you break that stream, it can simply continue the mission—placing an interesting challenge on jammers. In fact, a lot of people like to fly it in this manner until it gets to the target, and then they take over remotely—reducing the utility of a jamming.
There is also GPS jamming, which, as mentioned before, has issues in any kind of populated environment. But even with GPS jamming, most of the fail-safes tell it to go into a hover or loiter mode until they regain GPS. That means you have to keep the jammer on it continuously, until it runs out of battery and goes into auto-land or crashes. Such an approach is also a challenge against multiple drones at once, unless you use blanket GPS jamming, which creates other problems.
Now that brings us to physical solutions. The challenge did not allow kinetic takedowns or directed energy, because we are looking at solutions that could be used over an urban environment—you can’t shoot off a SAM or a high-energy laser in a city. So we only ended up getting physical takedown solutions that were essentially nets. SkyWall, a shoulder-launch net gun and one of our finalists, stopped everything it intended to. The problem is that even though physical was a near- guaranteed takedown method, it is generally used in short range. So depending on what the attack vector is, the drone might already be too close to stop it with a physical takedown.
TCB: Does it seem likely that counter-UAS measures will be able to adequately reel in the threat in the future?
MB: In the future, yes. Today is much more challenging. Small UAS’ have been commercial market-driven—rather than military driven—and because of that, they didn’t have that direct interplay with simultaneously thinking about the counter measures. So there is a disconnect now, but in the future, we will be able to safely counter them.
JR: When you are talking about what the military can do in overseas operations, you get rid of some of the restrictions—you can use shoot things down in unpopulated areas without worrying about collateral damage. Now, it is a matter of realizing it is a cat-and-mouse game between UAS innovation and counter-UAS innovation. The question should really be about evolving tactics, as well as evolving technology.
