In the skies over Ukraine, a new epoch in air warfare is emerging: drone-on-drone combat.
These aerial duels don’t involve bullets, missiles or bombs. In some, hobby-type camera quadcopters that are used to spy on enemy positions simply ram each other in a crude aerial demolition derby. In other encounters, highly sophisticated craft use advanced radar—backed by artificial intelligence and the latest aerospace engineering technology—to precision fire nets that snag other drones.
“This is something we haven’t seen before,” says Caitlin Lee, who leads the Center for Unmanned Aerial Vehicles and Autonomy Studies at the Mitchell Institute for Aerospace Studies in Arlington, Va. “This is the first time we’re seeing drone-on-drone conflict.”
And the action in Ukraine suggests that even more novel kinds of aerial conflict—including combat drones armed to fight in tandem with piloted aircraft—are coming to the broader world of warfare. The U.S. Air Force, for example, now envisions a fleet of 1,000 high-performance uncrewed aircraft paired with its most advanced combat jets. This plan is in response to China’s growing challenge to the U.S. military’s 75-year air dominance. Beyond the battlefield, weaponized drones could, from the skies above any city, easily threaten things such as crowd safety at major sporting events, prison security and critical infrastructure. (Of course, much of the underlying technology is also expected to usher in changes for the good in the realm of peaceful applications. Drones have already been successfully used to rush extremely perishable donor organs to transplant patients.)
In Ukraine, the initial drone dogfights sprung from the proliferation of commercially available, low-cost, low-altitude aircraft, such as Chinese drone maker DJI’s quadcopter. People can creatively modify these hobbyist machines for combat to allow the drones to conduct overhead surveillance and drop grenades. Defending against such small drones, some weighing just a few ounces or pounds, is difficult. For starters, they are hard to detect.
“We can retrain air defenses to look for smaller radar cross sections, but then they’ll pick up every bird that flies by,” says Sarah Kreps, director of the Cornell Brooks School Tech Policy Institute. “So it’s a real sensor problem that countries like the U.S. have spent billions trying to solve—not unlike when the U.S. spent [heavily on] countering improvised explosive devices that were far less expensive or sophisticated than systems our militaries had been trained to destroy. These are essentially flying IEDs that have foiled militaries in similar ways, creating asymmetric advantages that have been difficult to counter.”
Another challenge these small drones present is that they are now widely available and cheap enough to be purchased in large numbers. Even though an individual machine modified for combat is not capable of causing massive destruction, the number of potentially vulnerable targets is nearly infinite, Kreps notes. This enables a group with fewer resources to attack a more powerful foe.
In 2016 French special operations forces deployed in Syria were among the first to see small commercial drones imaginatively converted into instruments of war when the forces were attacked by Islamic State fighters. “Less-funded countries now have access to airpower where they wouldn’t have in the past, so that’s changing who’s entering the fray,” says Nicole Thomas, division chief for strategy at the Pentagon’s Joint Counter-Small Unmanned Aircraft Systems Office, an organization created in 2020 to synchronize the U.S. military’s response to such threats.
The U.S. government divides small drones into three categories: Group 1 describes craft that have a gross takeoff weight of up to 20 pounds. Group 2 covers the next tier, between 21 and 55 pounds. And Group 3 encompasses uncrewed drones that can weigh as much as 1,320 pounds.
While the drone war era has clearly begun, it is not yet clear that these small aircraft are playing a decisive role in the larger Ukraine fight by creating an offensive breakthrough or an opportunity to seize the initiative for one side, Lee says. “I think the open question is: Do the drones have to get more sophisticated … in order to hold the ground, let alone contribute to a combined arms campaign that actually takes back territory?” she adds.
Defense experts are not waiting for small drones to become more advanced before taking steps to defend against them. In the 2021 National Defense Authorization Act, the U.S. Congress directed the Pentagon to create a plan for developing and fielding defense systems to counter small drones. And this year the Pentagon plans to spend nearly $700 million for counterdrone research and development, plus $78 million for procurement. A private research firm estimatesthe market for systems to counter small drones will grow from about $2.3 billion in 2023 to $12.6 billion by 2030. This market includes not only the Pentagon but also state and municipal governments, as well as private entities.
That potential is inspiring more than a dozen companies around the world—including Blighter Surveillance Systems in England, and Dedrone and DeTect in the U.S.—to develop antidrone technology. Such systems may be ground-based, handheld or drone-based and can bring down other small aircraft using electromagnetic interference, lasers and other technology.
Fortem Technologies, a start-up based in Pleasant Grove, Utah, has vaulted into the drone wars by adapting its earlier work on miniature radars. The company says it has developed a complete system for detecting small drones—and capturing them midair with a net.
Fortem’s DroneHunter F700 has six rotors, a radar backed by autonomous technology and two “net heads” that can precisely fire webs at adversary drones. Once ensnared, smaller drones can be dragged away by the DroneHunter. Larger drones are also netted but then released; the net prevents them from flying, so they drop to the ground under their own weight. Then a parachute attached to the net deploys to soften the landing.
“We’re really the only one in the world at this point that can do that,” says the company’s chief executive officer Jon Gruen.
The U.S. government is using this technology to protect unnamed “strategic” sites. And Ukraine is flying Fortem’s new drone to patrol the skies and nab small Russian aircraft intact and on the fly.
Ukraine first deployed DroneHunter last May to chase down the Group 1 and 2 drones that Russia was using to spy on frontline Ukrainian troops. DroneHunter has dented Moscow’s ability to use drones for collecting artillery-targeting data on Ukrainian troop positions and has stymied larger kamikaze drones aimed at critical infrastructure.
When Russia began launching the Iranian-built uncrewed aerial vehicle Shahed, a Group 3 drone, as a kamikaze weapon, Fortem began modifying DroneHunter to intercept these armed drones. The system has ensnared more than 5,000 target drones during developmental flight tests, Gruen says. This has helped capture the attention of capital venture divisions at Lockheed Martin, Boeing and other giant corporations, which have invested $75 million in scaling up Fortem’s operations.
Significantly, DroneHunter operates autonomously: once deployed, it races to the action, makes independent decisions about all its moves, nets its prey and returns to be equipped with a fresh net.
“There have been debates about using autonomous drones in combat, and thus far, countries seem to have shied away from using them in a lethal capacity,” Kreps says. “At the same time, though, we’ve seen an increasingly porous line between the semiautonomous drones—which is how the U.S. used drones for counterterrorism—and fully autonomous drones.”
In a situation such as the one in Ukraine, where the West broadly supports giving the country the tools it needs to defend itself, “there could be a real first-mover advantage in using counterdrone systems in this type of autonomous capacity,” Kreps says, “which takes us further down the slippery slope of autonomy.”
Scientific American
