The threat of drone attacks by state and non-state actors is ever present and growing. Drones, or unmanned aerial systems (UAS), are cheap, expendable, and networkable, and are able to execute a myriad of kinetic and non-kinetic attacks on military and civilian targets. The United States and other nations face challenges in protecting their personnel and infrastructure from drone threats due to the ease with which drones can penetrate even the most robustly integrated air defenses.

In such a challenging threat environment, the United States and its allies must put forth great effort into countering UAS threats and helping to educate and assist small-state partners with limited technological capabilities and capacity. A key approach to developing counter-UAS (C-UAS) solutions involves categorizing the threat, leveraging experience and available technology, assessing current events, and developing new doctrine through training and imagination. The technology to counter drones already exists, as does some resident tactical experience for those service members who have encountered them. Service members and civilians around the world who have firsthand experience with drones, either in combat or through personal interest, could provide critical insights for employment and deterrence options.

This article examines the threats that drones pose, the current US regulatory environment, and the existing and potential responses to drones in both military and US civilian contexts. There is some overlap, particularly in C-UAS technology and response, but the threats and countermeasures differ considerably between these two environments. Although the article focuses on the United States’ use of and response to UAS, much of the discussion related to doctrine, regulation, and countermeasures can be generalized and adapted to the unique circumstances of allies and partners. Ultimately, mitigating the danger that drones pose in enemy and terrorist hands requires education and collaboration at every level of society.

Drones in the Military

Drones are not a new phenomenon on the battlefield. Great Britain and the United States began experimenting with drones in 1918, and although those drones were not tested in combat, the concept of remotely controlling an unmanned machine in flight did work.[1] Drone testing and remote flight continued during the interwar period, and by 1946, the US Air Force flew a remotely controlled B-17 from Hawaii to California.[2] Recently, an F-16 made a remote flight, suggesting that air-to-air combat can now be accomplished without a human in the cockpit.[3]

Being on the receiving end of indirect fire—artillery or mortar, in training or in combat—can be a stressful experience. Effective indirect fire usually means that a skilled observer was able to call in those fires. Across today’s battlespace domains, drones have become observation platforms equipped with various cameras and sensors to find enemy targets and send targeting data back to artillery units to deliver effective indirect fires, while the human operator remains in the safety of a protected location. For more than two decades, the United States and its allies and partners have employed drones to conduct surveillance, reconnaissance, and target engagement with great success. However, numerous adversaries now use drones for the same purposes.

What Is a Drone and What Can It Do?

For the purposes of this article, a drone is an unmanned remotely controlled machine. In general, actors design drones for use on land and water—as demonstrated by recent operations in the Black Sea—and, of course, in the air.[4] The US Army categorizes potential adversary drones in five groups based on size, from smallest to largest, and considers drones in Groups 1 and 2 to represent the most unique threat category. Drones in Group 1 are classified as “micro/mini UAS” and weigh under 20 pounds, while drones in Group 2 are classified as “small tactical” and weigh up to 55 pounds. The devices in Groups 1 and 2 are the hardest to defend against because they are difficult to detect even with sensors, much less the naked eye.[5] Though small, these drones have been known to drop grenade-sized munitions and can be rigged with small-payload explosives.[6] The term “drone” also includes the common quadcopter. These drones are available for public purchase in brick-and-mortar hobby and electronics stores and on the internet and are used for purposes such as photography, surveying, racing, hunting, and fishing.

US service members and allies and partners can vouch for the effectiveness of drones in combat, where an opponent can quickly learn to operate drones and leverage their capabilities to achieve a battlefield advantage. I have personally witnessed attacks from drones in operational and combat theaters. In each case, the implementation of easily accessible drones with weaponized modifications allowed both friendly and enemy forces to change the threat environment. During the US-led war in Afghanistan, the Taliban were quick to embrace this technology, learning to modify drones commonly used by hobbyists and private businesses to conduct reconnaissance and target coalition forces. These kinds of developments fundamentally change security considerations for offensive and defensive operations by affording some parity in conflict, and require a new type of analysis for offensive and defensive operations.

Fortunately, service members are taking note of the challenges drones impose and are analyzing the gaps in tactics and doctrine. Marine Corps 1st Lt. Walker Mills documented drones as an effective “suppression” technique, arguing that the presence of a drone is enough to immobilize an infantry unit without firing a shot.[7] Subordinate units face a serious indirect fire and counterattack threat when their position is fixed by an opponent’s drone. The enemy can then direct armed drones on the objective, leading to friendly mission failure, possible casualties, and the need for a higher-level response to recover the wounded and assets.[8]

Today, actors with limited resources may be able to level the playing field against asymmetrically superior opponents with even a small number of drones.

Today, actors with limited resources may be able to level the playing field against asymmetrically superior opponents with even a small number of drones. A single drone with the capacity to attack a maneuver unit that has no organic anti-drone weaponry or training may be an attractive asset for an adversary with limited resources. Furthermore, if a drone manages to detect and compromise a unit maneuvering on the ground, the compromised unit might be forced to request headquarters to divert unforecasted resources, such as exfiltration aircraft with an unknown response time. Essentially, drones can force a unit without drone countermeasures to hide until the drone leaves the area or conditions change in ways that are unfavorable for drone operations.

During the early days of the Russo-Ukrainian War, news reports informed the world about innovative Ukrainian drone operations and their effectiveness against unprepared Russian forces.[9] Defense experts praised the wartime ingenuity of Ukrainian soldiers, who fastened explosives to personally procured drones and flew them against the Russian aggressors with significant success.[10] This conflict-driven innovation was not an entirely new tactic, however, and while supporters applauded the Ukrainian efforts, it has become clear that the Russians learned from these experiences and have developed offensive drone and counter-drone tactics of their own.[11] Pro-Ukrainian groups have crowdfunded money and resources from around the world, including materials for the 3D printing of customized drone payload canisters.[12] These canisters, laden with explosive payloads and affixed to the aerial devices, offer a cheap, effective and relatively safe offensive warfighting option for Ukrainians.[13] Larger companies have also donated parts and labor to support Ukrainian efforts, while symbiotically expanding their place in the drone industry in the name of innovation and investment.[14] As the conflict in Ukraine continues, each side is constantly developing new drone tactics, with support from its allies, that the other side then has to counter. For Russia, this means partnering with Iran and China to stay ahead.[15]

What Does Current US Military Doctrine Say?

The US doctrine to assist maneuver forces in protecting themselves against adversary drone encounters is limited. Written by the US Army’s Air Defense Artillery Branch, the Army Techniques Publication (ATP) 3.01-81 Counter-Unmanned Aircraft System Techniques is intended to provide:

planning considerations for defending against low, slow, small (LSS) unmanned air threats during operations. This ATP also provides guidance on how to plan for, and incorporate, C-UAS soldier tasks into unit training events. This ATP offers planning guidance to brigade and below-level forces when regional threat estimates include the smaller unmanned aircraft system (UAS) platforms.[16]

As this ATP’s stated purpose makes clear, the US Army does not have one specific TTP (Tactic, Technique, and Procedure) to counter drone threats, but recommends planning, reporting, and situational awareness to prepare for drone encounters.[17] We know why and how friendly forces use drones during combat and security operations, and observers can determine enemy intent based on a drone sighting or encounter. The ATP suggests that maneuver units avoid drone attacks by using sound and light discipline common to any tactical scenario, regardless of the presence of drones:

Use optical and noise reducing measures to limit the glare or noise of equipment. Placing mud on headlights and using camouflage nets to obscure the glare of windshields … prevents friendly forces from drawing attention to their position. Using a noise blocking barrier and foam will lower the noise of operating equipment.[18]

Though tactically sound, the guidance in the ATP is not always feasible when encountering drones. A surveillance drone operator can rapidly deploy a drone to confirm or deny a suspected enemy action, giving the targeted force little time for mitigation. Such surveillance drones are typically equipped with cameras to gain and maintain contact with targets until directed to return to their operator (or are neutralized by the target on the ground). As such, these surveillance platforms are likely to identify a target regardless of the ATP’s recommended concealment techniques.

The counter-drone ATP indicates that commanders have the responsibility to take necessary action to ensure the safety of their soldiers according to the established rules of engagement. Furthermore, commanders are authorized to delegate engagement authority to individual soldiers encountering small drone threats, acknowledging the difficulties associated with engaging via direct-fire weapons systems.[19] Individual soldiers or small groups of soldiers will likely only draw attention to themselves if they attempt to shoot a small drone with individual weapon systems. With the speed of some small drones reaching 70 kph, striking one would be more a result of luck than sound tactics.[20] Task number 44-1-100 in the ATP offers little help as it provides only the tactic of engaging aerial platforms with all available small arms, including machine guns.[21] The task appears simple, but engaging a small drone without first clearing the field of fire carries considerable risks, such as fratricide or collateral damage.

The ATP is well-intentioned, but it leaves important questions unanswered. For example, how can commanders successfully train units in C-UAS at the home barracks? What should be done about the risks associated with soldiers firing errantly against small- and fast-moving drones? How should the maneuver force adjust its C-UAS tactics in urban environments? What fire control measures should the maneuver unit adopt to successfully disable a drone? If a drone compromises a maneuver unit, what factors should that unit consider in deciding to disengage from or abort an operation altogether? Finally, how should doctrine address defensive measures against multiple drones? These questions are crucial in a time when a single drone could compromise an entire unit.

These questions are crucial in a time when a single drone could compromise an entire unit.

Vital questions arise regarding offensive operations as well. Who should have oversight of offensive drone operations, and to what extent? How will the demand for drone video footage be deconflicted between units maneuvering on the ground and command posts synchronizing the operation? Should the rules of engagement account for the potential use of semi- or fully autonomous UAS systems operating in concert with friendly forces? Who will have access to counter-drone assets, and what will be the deconfliction requirements and considerations to use them? It is key to consider how to arm and empower operators at the lowest echelons to rapidly dispatch single and multiple Group 1 or 2 drones.

National interest surrounding the issue is reflected in the April 2023 Congressional Research Service report, titled “Department of Defense Counter-Unmanned Aircraft Systems.” The report poses several potential questions for Congress to address concerning the development and acquisition of Department of Defense (DOD) C-UAS systems and safety protocols:

• Is DOD funding of C-UAS systems appropriately balanced between research and development and procurement programs?
• To what extent, if at all, has the designation of a DOD executive agent for C-UAS reduced redundancies and increased efficiencies in C-UAS procurement?
• To what extent, if at all, is DOD coordinating with other departments and organizations, such as the Department of Homeland Security, the Department of Justice, and the Department of Energy, on C-UAS development and procurement?
• Are any changes to airspace management, operational concepts, rules of engagement, or tactics required in order to optimize the use of C-UAS systems and/or deconflict with other US military operations?
• To what extent, if at all, is DOD coordinating with the Federal Aviation Administration and international civil aviation authorities to identify and mitigate C-UAS operational risks to civil aircraft?[22]

Innovation in the Department of Defense

The DOD must develop systems to identify drones of all shapes and sizes, along with plans of action to neutralize potential threats.[23] As mentioned previously, the complexity or asymmetric style of an attack may be determined by the imagination of its planner, who could, for example, disguise a drone as a bird. Avian scientists are already modifying drones to appear as birdlike as possible to enhance their studies of migration and bird behavior, and it follows that an enemy might disguise an attack the same way.[24] Considering such creative offensive drone threats, policy makers and first responders would be wise to consider creative defensive options as well.

Companies such as the Civil-Military Innovation Institute (CMI²) offer training and scenarios designed for military units that expect to encounter drone threats.[25] These organizations, working with their military counterparts, can develop data-based models to further customize scenarios that lead to the most effective counter-drone threat techniques and doctrine. Encouraging collaborative efforts between national training centers and companies like CMI² can create a competitive advantage that enables the DOD to stay ahead of future threats.

For commanders and units, the DOD must integrate drone defeat scenarios into Mission Essential Tasks and then develop training evaluation scenarios that incorporate these skills. As a possible option, units could integrate drone-specific tasks into training mission profiles as preparation for both annual training requirements and pre-deployment validation requirements. Because drones are a threat to all military forces, the joint force should collaborate to develop a doctrine that each joint component can apply to its specific operations doctrine as the collective expertise from each component will also provide holistic recommendations for offensive and defensive drone procedures.[26]

Another effective way to develop sound drone and counter-drone strategies is to create new organizations or training centers for these purposes. These training centers could focus on concepts to incorporate the most recent TTPs to support real-world applications. Such a center would also benefit greatly from collaboration with industry to leverage civilian specializations and data collection to develop solutions to counter drone threats in myriad scenarios. An international, collective approach that incorporates experience from many defense perspectives in regions facing the same challenges could create a desirable solution.

It is imperative that all service communities contribute to the discussion, so that scalable counter-drone tactics might be developed for implementation across applicable domains. Drone defense will look different in maritime environments versus aerial or urban environments Tactics appropriate for infantry squads will look different from those required for larger units. An infantry squad, for example, might employ tactics to hide from a drone, while security forces might employ tactics to guard an airfield from a reconnaissance drone. The infantry unit might use camouflage and physical cover to hide themselves, while airfield security forces might focus on disguising key components and aircraft.

Drone threat awareness should be infused into all aspects of education, training, and testing. For example, individual skill testing might include counter-drone attack scenarios along a path to earn a coveted badge such as the US Army’s Expert Infantry Badge. Collective training events such as a company-sized field training exercise might include scenarios in which soldiers must prepare and emplace sound drone countermeasures such as effective camouflage or simple deception tactics to mask activities. Essentially, the drone threat today should be considered on par with threats such as adversary intelligence collection from individual service member social media accounts.

Drone threat awareness should be infused into all aspects of education, training, and testing.

Innovation at the Academy

Another way to combat the drone threat is to enlist the help of service members and experts who have experience with drones. The perspective that soldiers provide based on their interactions with drones is perhaps one of the best ways to identify counter-drone solutions and test defense options. US Army National Guard Sergeant Mickey Reeve, for example, used his computer science coding expertise to develop counter-drone software, enabling soldiers to participate in counter-drone training within a simulated environment that allows them to address numerous threat scenarios.[27] His contributions won the inaugural US Central Command’s Innovation Oasis competition, and the software is under rapid production for dissemination to the force. Sergeant Reeve confirmed the need for defense concepts to come from tactical-level practitioners, stating that “my experience with counter-UAS provided a catalyst for me to build out the solution … with my team here .... And everywhere I go right now, I’m seeing that there are talented service members out there with the solutions to the problems that are facing most of our operators in this environment.”[28]

Future warfighters are training with drones, experimenting with tactics, and visualizing a battlefield where drones are commonplace. The US Military Academy has begun incorporating drones into Cadet Leadership Development Training (CLDT). Cadet engineers are building drones to meet specific capabilities, while maneuver-minded cadets are using drones to conduct reconnaissance on mock objectives. Training often includes techniques from operational and training after-action reports to help cadets make modifications to improve drone operations for more effective mission execution.[29]

Placing drone technology in the hands of young leaders will help to generate effective offensive and defensive drone protocols for present and future fights. Providing new technology to prospective leaders in training and laboratory settings can prepare new soldiers for conflict, generate innovative methodologies for training, and foster a literacy for new doctrine. The US Army and the other US military services should continue to expose their personnel to drone operations as they develop in conflict. Applying those insights from conflict in training and during evaluations will help to enable readiness for drone operations in future conflicts.

Drones on the Homefront: Threat, Policy, and the Case for New Regulations

If commercially available drones can be used in active conflict zones, then they can be used in areas that are normally free of conflict. For example, someone could easily configure a drone to fly into an electric utility substation or carry conductive material to drape over power lines to create a live power arc and subsequent blackout. In the wrong hands, drones provide a new vector of attack and the potential to disrupt civilian infrastructure and generate chaos.

Although the United States has drone regulations in place, the government is unable to effectively monitor most drone usage. Section 49 of US Code 44809, “Exception for Limited Recreational Operations of Unmanned Aircraft,” explains the general provisions for recreational drone operations within the United States.[30] The provisions of the code are generous in their specifications for recreational use of drone aircraft by anyone wishing to operate one. The code requires unmanned recreational aircraft to be registered and display registration markings, and for the operator to have proof of registration.[31] But what if the operator chooses not to register the aircraft? Should law enforcement officials demand proof of registration? Do police officers understand drone regulations? These considerations do not necessarily have to infringe on personal freedoms, but they should inspire discussion among decision-makers and law enforcement officials before a violent event occurs.

The US Federal Aviation Administration (FAA) passed the UAS Remote Identification requirement for drones and drone operators in September 2023.[32] Remote ID is the ability of a drone to broadcast its identification and location information to other parties. However, the requirement, while sensible, seems more of a suggestion than a mandate, as the FAA acknowledges that a lack of remote identification broadcasting modules and FAA-approved identification areas limits enforcement.[33]

Policy makers and first responders should review current regulations concerning drones to see if the intent of the regulations can be realistically achieved. The United States may need to consider a new regulatory framework concerning the legal operation of privately owned drones as well as new national policy and potentially dedicated task forces to stay ahead of such an emerging asymmetric threat. Simply assigning extra duties to already burdened domestic law enforcement agencies is likely to be less effective than directing specific organizations to take the lead on managing drone use. It is also critical to identify who will enforce regulations at the municipal level.

Detection, Deterrence, and the Threat to Nuclear Plants

Between 2015 and 2019, 57 unidentified drone swarm incursions affected 24 nuclear power plants in the United States.[34] An alarming factor regarding these incursions is that not all of the drone operators or their operating locations were identified; as of May 2023, 49 of those 57 incidents remained unsolved.[35] A major point of concern is the inability to consistently detect drones and pinpoint drone operators.

Security around a nuclear plant is generally high and includes enough protective infrastructure to prevent most external threats, but drones and drone swarms are a new threat. Vulnerable infrastructure around nuclear reactors might be easier to target now given that previous defensive measures did not account for drones. If so, experts may need to consider new security measures and procedures to protect nuclear facilities and other national infrastructure from compromise, or update construction plans in view of the potential threat from drone swarms. Some of these construction plans may need to focus on better protecting physical infrastructure that supports critical operational components of the larger facility.

A case in point is the Palo Verde nuclear power plant, which has experienced several incursions in the last ten years.[36] The Palo Verde plant, located in Arizona, is the largest nuclear power plant in the nation. Its output supplies millions of people with power in the southwest United States, enabling economic capacity and livable conditions for residents in the desert heat.[37] Security planners equipped the plant with systems to detect drones and drone operators within 13 miles of the plant; however, reported incursions suggest that the current protection has been circumvented.[38]

In terms of deterrence measures, it seems that existing defense technology and punitive consequences for flying a drone in unauthorized spaces are insufficient. The FAA states: “The agency wants to send out a clear message that operating drones around airplanes, helicopters, and airports is dangerous and illegal. Unauthorized operators may be subject to stiff fines and criminal charges, including possible jail time.”[39] Although that message is out, reports of unauthorized drones continue, compiled into an open-source database on the FAA website, which reflects eight years of sightings.[40] The FAA states that it receives over 100 new reports of unauthorized or illegal drone operations each month.[41]

Drone activity is unlikely to end, and it is important to remember that not all drone activity is nefarious. However, in light of these reported incidents, facility planners should reassess their infrastructure and seek improvements to guard against future incidents. Some of the improvements could be as simple as obscuring certain access points of the facility or locations of supporting infrastructure that could be susceptible to compromise. Other solutions may require additional construction to increase protection around portions of the facility that power other areas of the plant. In the future, sites like Palo Verde may need to consider a layered defense that could include a security ring around the perimeter to detect and defend the plant before the drone reaches the site.

Regulatory Considerations for Domestic UAS Threats

Regulatory bodies, such as the FAA, play a large role in regulating drone activity, including enforcing safety, awareness, and compliance.[42] Equivalent organizations in a smaller nation’s governmental system could take steps to help ensure safety and reduce illegal and illicit uses of drones. Establishing rules and regulations can aid nations in separating bad actors who intend to utilize drones as weapons from hobbyists and other legitimate users. Following is a list of recommended policies for a partner nation’s regulatory body:

• Require remote pilot licensing and the registration of every drone within the country, regardless of intent to fly or origin of purchase.
• Reinforce this policy with escalatory penalties. Penalties could include expensive fines, revocation of permissions, and criminal charges.
• Conduct random verifications of UAS registration and remote pilot licensing. Updated considerations will create the sense of an all-seeing regulatory authority despite manpower and funding limitations. Increase awareness of regulations and safety protocols through media channels.

Each nation will need to consider how to ensure the safety of its citizens and defend against “lone wolf” drone operations while respecting civil and constitutional rights. Officials should be careful to avoid turning to overly authoritarian restrictions and intrusions on civil liberties while assessing drone threats and identifying solutions.

Conclusion

Drones are an established fact on the battlefield, and a potential threat on the civilian front. Although it seems there are currently few feasible steps a nation can take to fully deny the threat of drone terrorism short of a total ban, a layered approach to C-UAS that includes drone education, innovation, collaboration, doctrinal adjustments, regulatory initiatives, and potential organizational change will be necessary for defense to be effective.[43]

For the military to generate effective defenses against drones operated by hostile actors, we need to educate our forces about drone capabilities and classifications. Coherent doctrine and training developed by a joint conference that includes experience from all service components and operational levels is the best approach to identifying the most effective drone defense measures. Developing solutions at lower echelons and scaling requirements for larger-scale defense may also be a useful approach. Correctly characterizing the nature of the drone threat matters when seeking to apply technological solutions to the problem; it also helps us to ask the right questions, such as why would an adversary opt for a drone strategy in the first place?

Establishing a joint military and civilian organization composed of service members and civilians with real-world experience, who can assess, adapt, advise, and execute offensive and defensive drone operations creates a framework for concepts to counter drone-enabled terrorism on the homefront. It also allows other military units and civilian organizations to focus on performing the essential tasks required to win in conflict. Key to the structure of this new joint military-civilian organization will be the ability to rapidly acquire and test new counter-drone technologies to remain at the cutting edge of C-UAS.

Empowering the public to share their own ideas should happen in concert with other defense planning. Ideally, this sharing of ideas could take place in municipal government meetings focused on emergency response and preparedness in cities and towns. It is imperative to use our imaginations to conceive of seemingly unimaginable threats in order to prevent them. We cannot forget the tragedies of Pearl Harbor and 9/11, and we have to consider how drones were used to aid in the assassination attempt on President Trump, similar to the way they were used in the attempt on Venezuelan President Maduro.[44] We should not become complacent. If we have learned anything from the war on terror, it is that enemies will find ways to infiltrate communities and do harm to citizens however they can.

If the United States reevaluates its current UAS posture and effectively enforces drone regulations, it could then lead the way in exporting recommendations and counterterrorism solutions to the international community. The greater benefit of sharing knowledge with trusted international partners is for all to have access to the expanded perspectives and experiences from hostile drone encounters all over the globe. To counter drone threats globally, allied nations should seek to consolidate experience, accumulate and deploy resources, establish laws, review existing regulations, and potentially create organizations tailored to manage emerging drone threats. In all cases, insights concerning the best use case for drones and how to counter them are probably best suited for a collaborative environment where military and civilian leaders and planners can share experiences and recommendations.

Readers who would like to offer their perspective to inform emerging counter-drone doctrine can contact the proponent of ATP 3-01.81 at the United States Army Fires Center of Excellence, ATTN: ATSF-DD, 700 McNair Avenue, Suite 128, Fort Sill, OK 73505.

About the Author

MAJ Ian McAlpine is a US Army Special Forces officer.

This is a work of the US federal government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

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