The popularity of drones continues to grow. The FAA estimates nearly two million drones will take to the sky this year. There are many powerful applications for drones in use or in testing, including goods delivery, surveillance and inspection, search and rescue, agricultural monitoring – even forms of medical support to remote areas or hard-to-reach disaster zones. While drones have the potential to improve our lives, they also create problems.
Off-the-shelf drones can already deliver contraband to prisons, disrupt airports, and be used as makeshift bombs. A January article in Popular Mechanics detailed the closure of Heathrow Airport (London) “following a drone sighting near the airport, less than a month after another drone incident shut down neighboring Gatwick International for 36 hours.” The risk here is an unexpected drone sighting causes a dangerously erratic pilot response or an actual aircraft-drone collision which, despite the relatively small size of drones, would be catastrophic according to researchers at the University of Dayton.
Perhaps not as alarming, the capabilities of today’s drones, including package transport and high-resolution video and photos, make them a threat to privacy and security for many facilities and organizations, including jails and prisons. In South Carolina, an inmate escaped from prison using drone-delivered wire cutters.
Terrorists have successfully employed drone technology to a devastating effect in the Middle East for years. Their growing competency hints at the escalating terrorist threat domestically and sheds light on why Rotor & Wing International reported on an urgent need among security officials in the U.S. – including Homeland Security – for systems and technologies to counter potential threats from drones.
Methods for defending against drones can be simplified into two buckets: detection and mitigation.
Detection involves the discovery and localization of an unwanted drone, pinpointing its position and creating situational awareness. The four sensors used for detection include radar, radio frequency, acoustic, and visual (EO/IR). Each sensor has merits and drawbacks. It’s best to match sensor selection to your organization’s needs, your facility’s layout and design, and your team’s competencies and security goals.
The legality of radio frequency detection’s capture and decryption of signals and signatures is nuanced, but precedent does exist for the legal detection of signals emitted over open communication links. This basic form of radio frequency detection is defensible based on documented litigation. However, “overt” steps to extract and decrypt information delivered over a drone’s radio communication hasn’t been ruled on. A test case is required, thus it’s safe to steer clear for now.
While any one sensor can be used on a standalone basis, a combination can work effectively together and should be considered as part of a layered detection system where higher security requirements exist. The U.S. Military, for example, typically utilizes multi-sensor detection systems.
Mitigation refers to reducing the threat presented by an unwanted drone and essentially breaks down into two approaches: active and passive.
Active mitigation refers to proactive measures taken to eliminate or attempt to eliminate the threat. The most common active mitigation techniques include signal jamming, signal hacking, physically intercepting, and GPS spoofing. Physical interception often includes shooting projectiles or missiles, directing energy such as lasers or microwaves, or capturing the unwarranted drone with a net.
Passive mitigation refers to steps taken to reduce the effectiveness of the threat, without engaging with it directly. Such responses differ, depending on the responder and the perceived intent of the drone. At a jail, a response could entail locking down inmates, tracking a drone to intercept its contraband, and then tracking it back to its origin to apprehend the pilot. At an airport, it could involve air traffic control shutting down runways or diverting air traffic away from the threat.
Understanding the Law
Today, anyone can legally detect and passively mitigate drones (see prior commentary on radio frequency detection). Not just anyone, however, can actively mitigate drones. The Department of Defense, for instance, can take more aggressive action than a local county jail commander. Why? Because legacy legislation known as the “Aircraft Sabotage Act” (Title 18 U.S.C. § 32) classifies unmanned aircraft (i.e., drones, etc.) similar to manned aircraft and prohibits “damaging, destroying, disabling, or wrecking” of any aircraft. In other words, anything you can’t do to a commercial jetliner in the continental United States, you can’t do to a drone.
Agencies including the Department of Defense, National Nuclear Security Administration, Department of Justice, and Department of Homeland Security have all received relief from Title 18 restrictions, authorizing these federal entities to “track,” “disrupt,” “control,” “seize or otherwise confiscate,” or even “destroy” unmanned aircraft that pose a “threat” to certain facilities or areas in the U.S.
Where does that leave the majority?
Unless you are one of the federal agencies identified or actively partnering with them (e.g., during a National Security Special Event such as the Super Bowl), you can’t actively take down drones – even if they fly in your airspace without authorization. Simply put, you would assume all responsibility for your actions if you employ active mitigation technology.
That makes detection a first and necessary step for understanding and responding to this emerging threat. The situational awareness created by detection provides the ability to passively mitigate the threat. Once aware, you can build a threat response plan tailored to your facility. Further, detection often unearths the operator’s location – critical information required to apprehend the perpetrator and eliminate the potential for repeat offenses.
Our legislative process is imperfect. It’s probable that sensible updates to the Aircraft Sabotage Act will take years. Given that drones are becoming more powerful and more easily accessible, every security agency around the world knows the drone threat isn’t going away. Thus, it’s prudent to act now.