European officials went scrambling for solutions after Russian drones violated Polish and Romanian airspace on 10 September.

The incident seemed to remind EU allies that their modern jets and fancy missiles may not be up to the task of fighting the cheap, massed drone swarms of the modern air war.

The proposed solution is a “drone wall” defense initiative, with support from the world’s foremost expert on drone warfare, Ukraine.

No one knows how such a project would look, how much it could cost, or when it might be ready. Estonia, Latvia, Lithuania, Poland, Finland, Romania, Denmark, and Bulgaria will meet with the European Commission and Ukraine on 26 September to discuss the initiative. The EU hopes to have a roadmap by late October.

A game changer for Ukraine

Ukraine could make the EU’s drone wall actually work—if politics allows

Would the “drone wall” actually be a wall?

While “drone wall” is a striking name, some defense experts who spoke with Euromaidan Press said it may not be the best metaphor for visualizing how such a system might look in practice.

An effective anti-drone system would look much more like a dense, interconnected network of multiple overlapping layers of detection and interception. No layer will be fully effective by itself. Some layers may have to be switched out entirely over time, as new enemy threats render them obsolete.

“It is undisputed that defending against cost-effective long-range drones using fighter aircraft… or using expensive missiles fired from highly complex ground-based air defense systems, are not sustainable approaches,” German military expert Waldemar Geiger wrote for Hartpunkt.

However, “while a single interception attempt with (cheaper drone-based) systems may be cost-effective, establishing a comprehensive drone defense system is and remains very expensive.”

If EU countries hope to preserve both cost and operational effectiveness, they need to approach the problem with boldness and a great deal of political will, experts told Euromaidan Press.

What makes drone detection so difficult

Timely and comprehensive detection of hostile targets is a prerequisite for all other solutions. If the allies can’t see the target, they cannot shoot it down.

The first layer is intelligence, collected from space, the air, and the ground. In Ukraine, foreign intelligence sharing has repeatedly given defenders early warnings when Russia was about to launch missile and drone barrages, by tracking vehicle and supply movements within both Russian and occupied territory.

On the operational and strategic levels, both Ukraine and Russia are expanding the use of signals intelligence to locate drones in space, so that kinetic systems or other mobile UAV units can be launched against them, said Samuel Bendett, a Russia studies adviser with the American think tank CNA.

While radar is part of a well-rounded detection system, long-range strike drones from the Shahed lineage have been known to dodge conventional radar.

Ukraine has made effective use of acoustic sensors that can detect the characteristic whine of Russian strike drones’ engines, with the Zvook project dazzling NATO officials.

Ukraine’s Zvook: cheap and effective

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Other detection systems can include passive radar and low-emission 3D radar tuned to detect remote-controlled objects.

Airborne radar, also mounted on drones, is a critical part of the equation. Both attackers and defenders rely on intelligence, surveillance, and reconnaissance (ISR) machines during operations involving drones.

Bendett added that Ukraine has gotten good at knocking down Russian ISR units with FPV drones.

However, Russia has also evolved. The Rubicon Center of Advanced Unmanned Technologies has been a leading force in Russia’s drone war since 2024, systematically working on ways to strip away Ukraine’s strength in drones, layer by layer.

Rubicon units specialize in different tasks, such as countering Ukraine’s FPVs or hunting its reconnaissance units, which have been hit especially hard, according to the 5 September episode of Ukraine’s Dronefall podcast.

“From the point of view of using reconnaissance units, we see what the enemy is doing and we need to, at least, do the same thing,” Valentyn Prokopchenko, the head of air defense for Ukraine’s Khartia Brigade, said on the podcast. “Naturally, more reconnaissance aircraft are needed because there won’t be a situation where there are no losses.”

Why electronic jamming isn’t enough

Electronic countermeasures, which disrupt UAVs’ command and control, form yet another — some might say iffier — layer of defense for Europe.

Electronic jamming is easier to bring to bear against tactical drones in Ukrainian battlefields, but becomes progressively more expensive in deployment and power requirements when trying to target operational and strategic-level weapons.

Attackers constantly adapt to overcome electronic countermeasures, but fiber-optic drones are impervious to this disruption.

Ukraine’s Defender Media outlet reported that Russians are testing the use of radio-controlled and fiber-optic drones in tandem.

Bendett said attackers can use “frequency hopping” — switching command and control channels to reduce the chance of being detected or disrupted. Electronic warfare is not always effective against Shahed-type machines, he added, just as Russian ECMs have failed to stop long-range Ukrainian drones striking targets deep inside Russia’s territory.

Ukraine and the EU are also very different arenas when it comes to deployment of this tech. Ukraine’s airspace is closed to civilian aircraft. Not so in European countries, where large-scale jamming technologies can seriously mess with its extremely heavy civilian aviation traffic.

This caveat also applies to any drone detection systems, which may mistake a small civilian aircraft for a threat, and have to make the fateful decision whether to shoot at it or allow it to fly through.

Could cheap interceptor drones power the EU’s “drone wall”?

On the interception side, Ukraine has been at the forefront of developing small, cheap drones that can knock down long-range strikers, as well as their attendant observation units. Interceptor UAVs are a well-established and constantly updating part of Ukraine’s defensive strategy.

“They don’t have any effective countermeasures against UAV interceptors yet, but they’re searching,” Prokopchenko said on the podcast.

Interceptors run the gamut from plane-type systems, with reported speeds of up to 300 km/h, to even quadcopters. One Ukrainian developer of single-use interceptors, who asked not to be identified by name, produces machines ranging $1,500-$6,000 in cost.

In comparison, long-range Russian strike drones can cost in the tens of thousands.

Reusable interceptors, which can mount guns or explosive launchers to strike down hostile units, can potentially provide an even cheaper solution, in theory.

Furthermore, there’s a big tradeoff to consider between cost and effective range.

Another issue with the interceptor drone concept “is that it relies on skilled pilots,” wrote Fabian Hoffmann, a defense policy fellow at Oslo University. “While autonomous interceptor drones are under development, they are not yet mature, and their more complex system architecture will make them significantly more expensive.”

Short-range air defense systems: effective yet expensive to maintain

On the ground, the Ukrainians have also made use of fast wheeled vehicles networked together. These serve rapid response teams that can spread out along the drones’ flight paths, intercept them during an attack, and bring them down with automatic gunfire.

In the EU, defending countries are more likely to use weapon systems that are slightly less ad-hoc and more developed by defense contractors. These range from the venerable Gepard self-propelled gun, to the modern Skyranger, which can fire air-bursting rounds that saturate a target area with submunitions.

To protect more stationary targets, the EU states could employ fast-firing point-defense autocannons and other short-range air defense systems.

The more modern of these systems are relatively cheap to fire, but have a high up-front cost, with maintenance adding additional expenses.

Whether these systems can outcompete expendable drones in cost depends on specific production and deployment plans, among dozens of other variables.

Can legacy air defense systems adapt?

Expensive missile systems like the Patriot or France’s SAMP/T are likely to remain in use against enemy missiles, said Marc DeVore, who researched Russia’s invasion for the UK Foreign Office.

Indeed, Russians have frequently attacked Ukraine with a combination of weapons, flooding the airspace with hundreds of expendable drones, to allow a handful of ballistic or cruise missiles to slip through and do the real damage. Alternatively, air defense systems that focus on the missiles might miss more drones in the process.

DeVore told Euromaidan Press that manned fighter planes are still very capable of shooting down long-range strike drones with relatively inexpensive laser-guided rockets.

On the other hand, the high per-hour cost of flying a jet might offset this cost-effectiveness, depending on the operational parameters involved, other experts said.

DeVore further pointed out the difficulty of getting so many different solutions to cover a single airspace without posing a threat of friendly fire — after all, Ukraine reportedly lost at least one F-16 fighter in this way.

He suggested that one solution might be to delegate detection and interception duties to different parties, or create zones where one type of interception predominates. Alternatively, different layers of altitude can be protected by different systems. 

Integration is the main challenge

By themselves, these solutions are just building blocks. To build a “drone wall” of any kind, ”you have to integrate everything from the largest Patriot to the smallest interceptor drone,” Kirill Mikhailov, a researcher with the Conflict Intelligence Team, told Euromaidan Press. “All of this requires cooperation and collaboration on a so-far unprecedented level.”

That may be putting it lightly. Every analyst who spoke to Euromaidan Press emphasized both the critical need and the great challenge of creating interoperability solutions to process data quickly and figure out who needs to be shooting what. The Ukrainians have led the way here as well, with their battle management systems like Virazh and Delta.

To incorporate these lessons, European allies likely need to adopt automated big data solutions, DeVore said.

Data architect Daniel Connery emphasized the need for a “drone-agnostic software layer” with “secure, interoperable application programming interfaces.”

“Imagine a border sector where one vendor’s drones patrol during the day, another’s at night, and a third provides thermal reconnaissance,” Connery wrote to Euromaidan Press.

“If each has its own control software, integrating their feeds, scheduling rotations, and handing off tasks between fleets becomes nightmarish.”

The need to evolve

But even all of the above is not sufficient. A next-generation drone defense system of the kind the EU is envisioning has to be able to evolve dynamically over time, in response to rapid developments, not just in technology, but enemy strategy and tactics.

Again, Rubicon is the best example. “I’d say the Rubicon problem is much broader than just countering our UAVs that shoot down scouts,” Taras Tymochko, a consultant with the Come Back Alive Fund, told the Dronefall podcast.

“Because Rubicon, I’d put it this way — they taught the enemy how to fight.”