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By
Dan Gouré
September 20, 2019
U.S. Marine Corps photo by LCpl Dalton S. Swanbeck
There is a new urgency to the search for cost-effective counters to the growing threat posed by unmanned aerial systems (UAS) or drones. Large, high-flying UASs can be countered by anti-aircraft systems, although this is an expensive solution. But new answers are needed for medium and small drones, those that fly slowly and close to the ground. There has been a rush to field counters to the growing UAS threat which has produced dozens of potential solutions. As more candidate systems are tested and fielded it is becoming increasingly clear that one of the most cost effective and safest ways of countering the growing threat posed, in particular, by small and medium-sized drones is through electronic warfare.
U.S. great power competitors and rogue regional powers are rushing to acquire drones and integrate them into their military and unconventional forces. China is not only producing an array of sophisticated military drones but
flooding the commercial marketplace with small, cheap and reliable UASs. Russia is fielding a series of increasingly sophisticated military drones. The Russian military
employed some of these in eastern Ukraine to perform over-the-horizon targeting for its long-range fire systems. Iran is
reported to have employed armed UASs along with cruise missiles in the recent attack on Saudi Arabian oil facilities.
The use of UASs by terrorist groups in the Middle East and Africa has now become commonplace.
ISIS was one of the first such organizations to employ drones as a low-cost air force, for both intelligence, surveillance and reconnaissance, and to drop small explosives. While it is increasingly clear that the Houthi rebels in Yemen did not conduct the latest attacks on Saudi oil installations, there have been numerous documented cases of this group employing Iranian-made drones against Saudi targets, including
oil facilities,
infrastructure and even
military personnel. Hezbollah and Hamas are routinely
sending drones into Israeli airspace. Syrian rebel groups have executed
multiple strikes on Russian airbases employing Chinese-made drones carrying explosive payloads.
The use of drones by bad actors is spreading around the world. The Nigerian Islamist terrorist group Boko Haram is
operating better drones than government forces. Mexican cartels are employing cheap, short-range UASs to
move drugs across the southern U.S. border. There was even an
attempt by parties unknown to use explosive-laden small drones to assassinate Venezuela’s President Nicolas Maduro.
Closer to home, protest groups and individuals have flown drones into restricted areas. Frankfurt airport has been closed twice because of
reports of the presence of drones in the flight paths of commercial airliners. London’s Heathrow and Gatwick airports have had similar experiences. In the United States, individuals have used drones to spy on neighbors, friends and spouses. One Pennsylvania man was recently arrested for
attempting to use a commercially-available toy drone to drop explosives on his ex-girlfriend.
Confronted by a threat for which they were ill-prepared, Western militaries have struggled to come up with solutions to this new challenge. Traditional air defenses such as anti-aircraft missiles have been employed to down some types of UASs. Newer capabilities such as the U.S. Army’s Mobile Short-Range Air Defense system employ multiple kill mechanisms to
counter an array of low-flying threats such as helicopters, ground attack aircraft and drones. In the future, directed energy weapons also may be employed against drones. These have the advantages of near-instantaneous engagement and low cost per shot.
Defeating smaller UASs presents particular problems. Their size and quiet motors make them difficult to detect by sight or sound. Because they operate close to the ground and move slowly or even hover, they also are hard to track. But even if their location is known, defeating smaller drones presents its own problems. There is the risk of collateral damage caused by kinetic weapons that miss their target or from debris striking the ground. Then there is the cost, particularly if an adversary is using swarms of relatively cheap drones.
Electronic warfare (EW) looks particularly promising as a way of combating drones of all sizes and mission profiles. Using EW, the defender can trick or “spoof” the drone’s navigation system, jam its communications, defeat fuzes and weapons’ triggers, and even take control of the UAS. One of the earliest EW solutions to be fielded was
Battelle DroneDefender, a short-range rifle-like device that sends out an electronic signal that disrupts GPS and radio control signals. The drone either returns to its controller, maneuvers randomly or lands.
An even more effective and now proven EW solution is The Marine Corps’ Marine Air Defense Integrated System (MADIS). Based on Sierra Nevada Corporation’s battle-tested counter-IED technologies, MADIS uses a combination of radar and electro-optical sensors to detect, track and target drones and then fires a powerful electronic jammer to defeat the drone’s flight controls. There are
several variants of MADIS either fielded or in development, including a fixed version for bases, a standard system mounted on the Joint Light Tactical Vehicle and even a light MADIS that can be carried on an all-terrain vehicle. It is believed that this was the system, lashed to the deck of the U.S.S. Boxer amphibious warfare vessel, that
took down an Iranian drone in July in the Persian Gulf. The Marine Corps plans to enhance MADIS by adding either a killer drone or a laser weapon in the future.
Jammers and other EW systems can be mounted on virtually any platform, including attack drones. Large systems can reach out to engage UASs at higher altitudes and greater distances. One of the most significant advantages of using electronic warfare against hostile drones is the reduced risk of collateral damage. This is particularly important when protecting urban infrastructure such as airports and government buildings. The use of EW against accessible targets also allows the defender to save long-range, but more expensive, kinetic weapons for use against more critical targets such as manned aircraft or ballistic and cruise missiles.
