An emerging threat: Small drones as flying IEDs

The military is taking seriously the idea of drones, even small ones, not just delivering weapons but being used as weapons themselves.

Army engineers working at Yuma Proving Ground, Ariz., have demonstrated their ability to shoot down incoming unmanned aerial systems, adapting a system being developed to counter rockets, artillery and mortars to include UAS among its targets. Meanwhile, researchers at the Army's just-completed Network Integration Evaluation 16.1 tested small quad- and octocopter drones both to see what they’re capable of and devise ways of defending against them.

One reason for this type of research is the ubiquity of all kinds of UAS. "Every country has them now, whether they are armed or not or what level of performance,” Manfredi Luciano, project officer for the Enhanced Area Protection and Survivability, or EAPS, Army Technology Objective, said after the Yuma demonstration. “This is a huge threat has been coming up on everybody. It has kind of almost sneaked up on people, and it's almost more important than the counter-RAM threat."

Another reason is that small UAS also can avoid the detection by radar systems designed to spot airplanes, missiles and larger military drones, as a post by the Homeland Defense Information Analysis Center (HDIAC) notes. A case in point is the 2-foot-diameter quadcopter that flew onto the White House lawn in January, unnoticed by the White House’s radar. It turned out that drone was not a threat, but it could have been.

“I personally believe that the unmanned platform is going to be one of the most important weapons of our age,” Navy Capt. Vincent Martinez, commander of the Navy Surface Warfare Center (NSWC) EOD Technology Division, said in the HDIAC post. “I’m going to have to start thinking about not only how to diffuse the payload but how I defuse the platform. When I walk up on that platform, is it watching me, is it sensing me, is it waiting for me?”

HDIAC referred to the possibility of weaponized small drones as “flying IEDs,” a reference to the roadside improvised explosives that tormented U.S. troops for the duration of the wars in Iraq and Afghanistan.

Martinez said that even some small hobbyist drones could be armed with up to 6 pounds of C4 plastic explosives or several fragmentation grenades, which could do a lot of damage. And an armed drone might not come alone—the Army researchers at NIE were working on operating their drones in swarms, at one point having 10 in the air, simultaneously executing a flight plan. Swarms, researchers pointed out, not only could cause more damage but they also would increase the chances that one or more would get through, say, a base’s defenses, even if base personnel saw them coming.

While concerned about quadcopters and other small drones, the military also is working to defend against mid-size UAS. The tests in Yuma, carried out by researchers from the Army Research, Development and Engineering Center at Picatinny Arsenal, N.J., dealt with what the Army called an outlaw-class UAS made by Griffon Aerospace. In August, engineers shot down two of the UAS at kilometer range using command guidance and command warhead detonation, the Army said.

The military services are developing other ways of countering UAS. The Navy last year deployed its first anti-UAS laser weapon in the Persian Gulf. And the Marines and the Army are in different stages of development of vehicle-mounted lasers.

As the availability of UAS—large and small—continues to grow, the potential threat from them can’t be ignored. “Right now, we are in a period of tremendous uncertainty and trying to determine what the singular threat is going to be is a significant challenge,” said Jerry Leverich, a senior analyst with the U.S. Army’s Training and Doctrine Command futures directorate, adding that “a $100 device [such as a quadcopter or even model airplane] currently being used for surveillance can be quickly adapted for lightweight explosives.”