It was only a matter of time until U.S. troops had to face the new sky threat: armed drones.

Islamic State fighters in Mosul already have used quadcopters to drop grenade-sized bombs on Iraqi security forces, a U.S. commander in Iraq said recently. And drones are now so inexpensive and accessible that they can be bought at toy stores or online.

The military is wasting no time looking for ways to jam and destroy enemy drones, said Lt. Col. Dave Sousa, of Marine Corps Combat Development Command.

"This is not just the Marine Corps," Sousa told Marine Corps Times. "This is all services: Army, Navy Air Force and Coast Guard – other government agencies. Everybody is looking at this: Academia, DARPA [Defense Advanced Research Projects Agency], you name it."

The goal is to find ways to disrupt the link between the operator and drone, rendering it useless, or blasting drones out of the sky, Sousa said in a Jan. 25 interview.

"We're looking at everything from shotguns to water cannons to other kinetic means," Sousa said. "We are looking at lasers. We are looking at anything and everything that can help counter these threats." 

The Marine Corps is working with the Office of Naval Research to develop the Ground-Based Air Defense Directed Energy On-the-Move system, which would use a laser to target enemy drones, he said.


However, lasers may not be the right weapon to use against drones in densely populated urban environments, where the Marines expect to fight future wars, said Marine Capt. Matt Sladek, whose job title is counter unmanned aerial systems capability integration officer.

Lasers are direct-fire weapons, and if Marines are fighting amid a cluster of buildings that are several stories high, the lasers may not be able to hit drones that suddenly pop up above rooftops, Sladek said.

Drones are hard to detect because their radar signature is "minuscule" compared to those of manned aircraft, Sousa said.

"Being able to discriminate between what is a drone and what is a bird, just in your own neighborhood, would prove challenging," Sousa said. "In a hostile environment … you're trying to defeat these things as far off as possible."

At a Jan. 13 news conference, Army Col. Brett Sylvia said that U.S. troops have helped Iraqi security forces down nearly a dozen ISIS drones over Mosul.

Without getting into specifics, Sylvia said U.S. troops have been "able to bring to bear some of our technical capabilities" which the Iraqis were able to use with "much of their direct fire weapon systems."

Sousa declined to say what specific technologies Marines currently have to detect, track, jam and destroy enemy drones. The service has conducted operational assessments of the Battelle DroneDefender, which uses electromagnetic waves to jam drones within 400 meters.

"We're doing user evals on the DroneDefender, but I can't get into specificity of what we have or where we use it," Sousa said.

The proliferation of drones extends beyond terrorist groups like ISIS. On Jan. 12, 2016, an Iranian drone flew over  the carrier Harrier S. Truman while the ship was in international waters.

Sousa said the Marines hope to field new technology to counter enemy drones as soon as possible.

"If I could something out there today that detects, tracks IDs and defeats [drones] and it meets the expeditionary nature of the Marine Corps … then I'd get it today," he said.

This is where Marine Maj. Ho Lee comes in. Lee, of Program Executive Office Land Systems, is constantly working with the other services and experts both within and outside the Defense Department to determine what technology is needed to beat the drones.

"This is urgent," Lee said. "It's a threat now. It crosses all of the services. We're looking at how do we rapidly field something to [meet] an evolving technology. It's changing every day."