The U.S. Marine Corps is getting a new type of air defense weapon, a high-powered microwave that zaps drones out of the sky. Known as Expeditionary Directed Energy Counter-Swarm, or ExDECS, it is the latest version of the Leonidas weapon system made by Epirus. Previous versions have proven highly effective in tests, and the new ExDECS is tailored to meet the Marines’ requirements against the rapidly growing drone threat. Epirus have a press release on the new $5.5 million contract award here.
“At Epirus, we’ve been sounding the alarm bell on the dangerous evolution of drone warfare since 2018 and recognized early on the defining characteristic of UAS on the future of warfare since,” Andy Lowery, CEO of Epirus told me. “Just look at the numbers and there’s your lessons learned from Ukraine. That future that we talked so much about is here today—and we have the technology to defend against it.”
Countering Swarms: The Drone Numbers War
Both sides in Ukraine are deploying vast fleets of drones with numbers now stretching to millions. President Zelensky announced that Ukraine would produce a million drones this year, and Putin recently declared that Russia may produce as many as 1.4 million.
Reports from the front describe six, twelve or even thirty FPV kamikaze drones attacking every armored vehicle in an operation, leaving the battlefield covered in smoldering wrecks. The drones are so plentiful that when the vehicles are destroyed, two or three will pursue every surviving soldier fleeing foot. It is all a matter of cost: missiles are expensive and rare, but $500 FPVs are expended freely.
Electronic jamming, previously seen as the best solution to drones, has proven partially effective at best in Ukraine. Many soldiers in Ukraine carry shotguns to defend themselves against FPVs. These sometimes work, but the odds are getting progressively worse as the drones multiply.
“Even the best sharpshooters would be hard pressed to defend against fifty plus drones attacking simultaneously,” says Lowery
Existing U.S. defenses might be pushed to deal with this sort of onslaught, as even one drone getting through can knock out the defending weapon. But tackling masses of drones at once is exactly what ExDECS is designed for – that’s why ‘Counter Swarm’ is part of its name.
“A core differentiator of Epirus high-power microwave is our ability to defeat both individual drones and large swarms,” says Lowery.
Directed Energy: Effective And Safe
ExDECS has something in common with high-energy laser weapons which the U.S. is also fielding for counter-drone operations. Both strike at the speed of light, but while the laser focuses its energy on a small spot, the microwave weapon can emit a broad fan with an area effect. And while a laser may take seconds, ExDECS is virtually instantaneous.
“ExDECS emits a wide field of energy that disables all electronics within it,” says Lowery.
Microwaves affect different electronic components to varying degrees, causing anything from minor glitches to locking up to permanent burnout. Drones simply drop out of the sky. It may not be as dramatic as an explosion, but videos of tests with flocks of drones plummeting to earth (see YouTube link above) prove its effectiveness.
“Perhaps most importantly, it is cost efficient with drone defeats for five cents per shot,” says Lowery.
That cost matters against large numbers of drones. The Stinger shoulder-launched anti-aircraft missile is extremely effective, but at an eye-watering $480,000 per shot it is never going to be issued in large numbers. Even cannon fire can be expensive. A burst from the twin 35mm cannon of the Gepard vehicle used by Ukraine looses 48 rounds costing $600 each, so one burst costs about $29k. It typically takes several such bursts to down a Shahed drone, so the ammunition costs more than the target. 5 cents a shot is better value
The other advantage of ExDECS is that when drones are coming in at shoulder height from all directions, it can engage them freely without the risk of friendly fire casualties from cannon and missiles.
“We need to put less metal in the air,” says Lowery. “Epirus HPM emits a powerful, precise—and invisible—pulse of directed energy, with no risk of collateral damage nor blue force fratricide.”
Defending The Corps
Epirus’ previous model was tiny beside the shipping-container-sized unit produced by a competitor, and ExDECS is smaller still, thanks to compact, solid-state electronics. It has to be small because the Marines need a lightweight unit which can be towed behind standard vehicles for maximum mobility. Some counter-drone systems are designed to defend fixed bases, this one is all about movement
“ExDECS is designed for USMC’s EABO,” says Lowery
EABO or Expeditionary Advanced Base Operations involves the deployment of small, fast-moving groups from austere, temporary locations in potentially contested regions. A key feature of EABO is that they will take place within the range of tactical weapons. Given that small drones are affordable and effective and can be acquired by any state or non-state group, any future Marine deployment can expect to face hostile drone attacks from the outset. Hence the urgent need for mobile counter-drone capability.
In principle, the same technology could protect Marines against other threats too.
“Solid-state, software-defined, long-pulse high-power microwave—what we are doing at Epirus—has demonstrated effectiveness against a spectrum of electronic threats, including targets beyond drones,” says Lowery. “In theory, anything with an electronic pulse would be vulnerable to Epirus HPM.”
Epirus will deliver the first ExDECS to the Marine Corps Warfighting Lab by the end of this year. This will be integrated with the U.S. Marine Corps’ Common Aviation Command and Control System for field experimentation and “multi-platform testing in expeditionary scenarios,” as part of the Marine Corps Ground Based Air Defense capabilities.
Drones can be easily assembled from commercial components using nothing more than a screwdriver and a soldering iron, and they are universally available. Any opponent, whether a state or non-state actor, can field them by the thousand and strike from any miles away. Marine expeditionary forces are likely to be attacked by large numbers of such drones, and the protection that ExDECS provides will be a lifesaver.
