Unidentified drones have been seen during the night at airports throughout Europe. How concerned should we be?

Initially, there is a warning, that disembodied voice over the tannoy: “Your attention please. Air siren in the city. Please move to the shelter on the minus second floor.” Following that is the mosquito-like whine of the approaching Russian drones, gathering in their hundreds just above the clouds.

This is instantly followed by the clatter of anti-aircraft gunfire, the distant boom of explosions, and ultimately the foreboding wail of ambulance and fire sirens.

This encapsulates the stark truth of nighttime in Kyiv and other cities throughout Ukraine.

These are assault drones that detonate upon impact.

Drones have become an essential element of contemporary warfare, extending beyond the confines of the battlefield.

Across Western Europe, far removed from Ukraine, unarmed drones have also been observed hovering near airports, military installations, and energy facilities, all part of an alleged “hybrid warfare” campaign being carried out by Russia, with speculation rising that they are being sent to evaluate the endurance of specific NATO nations aiding Ukraine.

Recent drone observations in Poland, alongside a series spotted near critical infrastructure throughout Europe, including Belgium and Denmark, have incited anxiety amongst several NATO states.

Currently, there are discussions about establishing a “drone wall” designed to shield regions of Europe – but just how crucial is this really? And more importantly, how feasible?

On 9 September, around 20 Russian drones overshot Ukraine and ventured into Poland, resulting in the shutdown of four airports.

NATO aircraft were deployed and several of the drones were intercepted – the rest crashed across Poland, dispersing debris in numerous regions.

This served as a wake-up signal to Europe, representing one of the most significant and alarming intrusions into NATO airspace since the onset of the war in Ukraine.

Hence, the conversation surrounding a potential drone wall becomes increasingly urgent.

“This momentum is really propelled by these recent incursions,” articulates Katja Bego, senior research fellow in the international security programme at Chatham House think tank.

Drones – or to use their formal name, Uncrewed Aerial Systems (UAS) or Unmanned Aerial Vehicles (UAVs) – have already revolutionized the battlefield.

On the combat zones of eastern Ukraine, they are typically small, short-range units, measuring around just 10 inches, and they carry deadly explosive payloads.

However, these are not currently the threat to the remainder of Europe. It is the larger drones – some of which may fly well beyond 1,000km – that are igniting demands for a European drone wall.

Previously, Russia imported a variant known as Shahed 136 drones from Iran but has since developed its own model: the Geran 2. Some Gerans were among the drones that entered Poland in September.

So, what if, some now ponder, Russia were to deploy over 200 drones? Or even 2,000? How would NATO react – and indeed, could it respond?

After all, dispatching fighter jets each instance would incur significant costs. André Rogaczewski, CEO of Netcompany, a Danish IT services company that develops digital solutions for European governments, contends: “[It] is neither effective nor a wise investment of taxpayers’ money.”

Ukraine has intensified its own long-range drone strikes on Russian airports and vital infrastructure such as petrochemical facilities, bringing the conflict closer to everyday Russians.

Then there are maritime drones: uncrewed vessels capable of traveling above or below the surface, which have been used with devastating efficacy by Ukraine against Russia’s Black Sea fleet.

Yet there is something that is, in some respects, more malevolent than distinctly identifiable drones utilized by nations openly at war.

That is: the surge of enigmatic, unnamed drones that have emerged.

Occasionally, these appear in the wee hours, around European airports, including one at Belgium’s main airport near Brussels earlier this month. There have also been analogous sightings in Denmark, Norway, Sweden, Germany, and Lithuania.

In contrast to the distinctly identifiable Russian assault drones in Ukraine, these “civilian drones” in Western Europe have not – so far – been armed with any explosives. However, due to their anonymous launch, it is challenging to determine their origins or who activated them – or even if they are being launched from passing vessels.

The blame tends to land on Russia, with Western intelligence officials believing Moscow is utilizing proxies to deploy these short-range drones locally to create chaos and disturbance. The Kremlin denies any involvement.

Belgium serves as a notable target, being home to NATO headquarters, the European Union, and Euroclear (the financial clearing house managing trillions of dollars in international transactions).

There is ongoing discourse surrounding whether Europe should release approximately €200bn worth of frozen Russian assets, held in Belgium, to assist Ukraine. Hence, is it merely coincidental that mystery drones have surfaced around Brussels and Liege airports, as well as a military installation?

The UK has dispatched a team of counter-drone experts from the RAF Regiment, deployed from RAF Leeming in North Yorkshire, to help strengthen Belgium’s defenses against these drones.

Nevertheless, the unknown drones raise concerns: both due to the peril they pose to aircraft during takeoff and landing as well as the potential for surveillance, particularly surrounding military bases and crucial infrastructure like power facilities.

The initiative for a drone wall serves as Europe’s reaction to the risk of cross-border incursions by drones particularly launched from Russia.

The wall has been characterized as an integrated, coordinated, multifaceted defense mechanism that initially spans from the Baltic states to the Black Sea.

It will likely consist of a mix of radar, sensors, jamming, and weapon systems to identify incoming drones – and subsequently track and neutralize them.

EU foreign policy chief Kaja Kallas has stated that a novel anti-drone system should be fully operational by the conclusion of 2027.

Understandably, those nations most eager to see it implemented swiftly – including Poland and Finland – are geographically closest to Russia.

Katja Bego believes it is a necessity – and long overdue.

However, she adds: “This issue extends beyond drones. There are insufficient provisions in terms of more conventional missile defense, air defense, along the Eastern flank borders.”

Regardless, a drone wall does not serve as a universal solution for aerial defense. Others are skeptical about its complete practicality.

Robert Tollast, a research fellow at Whitehall think tank The Royal United Services Institute (RUSI), asserts that the notion of some “kind of impenetrable wall”, is, in his view, out of the question.

Yet he acknowledges the rationale for such demands and expresses a desire to attempt.

“For nations adjacent to the Russian border – including the Baltics, Poland, and Germany, as they are naturally in the range of those long-range drones – it is absolutely crucial to attempt constructing something like this,” he asserts.

“The intention here would not merely be to create a complete wall, or anything that’s entirely impenetrable,” agrees Ms Bego.

“It’s really not feasible – both in terms of the distance involved and the existing technologies are not 100% infallible… Instead, you should look at a mix of solutions that might effectively capture various types of drones and neutralize them.”

Fabian Hinz, a research fellow at The International Institute for Strategic Studies in London, elaborates a comprehensive range of options for detecting drones.

“You can utilize acoustic detection; airborne radars that can identify low-flying targets exceptionally well; ground-based radars with very short ranges against low-altitude targets, but [that] still perform admirably against higher flying threats.

“You may also employ optical systems, infrared technologies – and once detection has occurred, you have either soft kill or hard kill capabilities.”

Hard kill involves eliminating the drone, either via gunfire or missiles. Soft kill renders an incoming drone ineffective, usually through electronic interference.

Russia and Ukraine have been effective in circumventing soft kill measures on the battlefield by outfitting their drones with tens of kilometers of fiber-optic cable that unrolls while in flight, but that’s not a practical option for drones traveling hundreds of kilometers across borders.

Regarding hard kills, Mr. Hinz outlines numerous ways to achieve them: from surface-to-air missiles to fighter aircraft and helicopters.

“You could utilize lasers which might prove useful as well,” he adds, “but [these] are not quite the wonder weapon that many presume them to be.”

André Rogaczewski believes jamming can serve as a viable alternative. Ultimately, however, for any drone wall to be effective, it must be capable of addressing a wide array of airborne threats, potentially all converging simultaneously.

As tensions between Europe and Russia have escalated since Moscow’s full-scale invasion of Ukraine, other instances of so-called “hybrid” or “grey zone” warfare attributed to Russia have also increased, which the Kremlin typically denies.

These encompass cyberattacks, disinformation efforts, incendiary devices concealed within regional cargo depots, observation, and at times sabotage of undersea cables.

In a security forum in Bahrain earlier this month, Admiral Giuseppe Cavo Dragone, the Italian chair of NATO’s Military Committee, informed me that amidst all NATO’s defense needs currently, air defense remains the top priority.

The initial phases of the drone wall are anticipated to be operational within months, although not all specifics have been finalized.

Simultaneously, NATO’s Allied Command Transformation (ACT), situated in Norfolk, Virginia, is developing longer-term strategies. This presents a considerable challenge.

Mr. Tollast indicates that the primary difficulty of the drone wall is the vast expanse of territory that requires protection. “You require an extensive array of tactical radars for low-flying drones and larger radars for higher altitude threats, spread across thousands of kilometers.

“Moreover, you need cost-effective interceptors and forces prepared to respond at any time. It will never be foolproof, and even as the costs of certain radars and interceptors decrease, it’s very unlikely to be economical.”

The financial aspect remains complex. “This is a formidable defense issue,” notes Mr. Tollast. “Even with increased European defense spending, there will still be considerable competition from other sectors within defense [for that funding] – we require more ships, submarines, nuclear armaments, even satellites as well.

“Thus, a drone wall may continue to be a somewhat financially contentious topic for certain individuals.”

Potential funding could derive from a combination of EU resources, national budgets (particularly in Eastern Europe), and interest from frozen Russian assets.

Initially, Ms. Bego states that the drone wall referred to defenses along the Eastern flank, but since the EU has taken the lead on this initiative, they have broadened its scope.

“Everyone acknowledges that action is necessary, and there is a need for coherence and to mobilize funds for this, but the specifics concerning ‘who’ and ‘what’ remain hotly debated…

“The more foolproof the system you wish for, the costlier it becomes.”

Regarding the target date, Mr. Tollast perceives 2027 as quite ambitious – but adds, “they can undoubtedly achieve additional protection by that time.”

As these developments unfold, the challenge of erecting the wall grows increasingly daunting. Because as swiftly as novel counter-drone measures are implemented, a new type of drone threat appears capable of bypassing them.

This sets the stage for a contemporary arms race.

“The pace of technology advancement in this domain is hyper-accelerated, particularly in conflict scenarios,” says Josh Burch, co-founder of Gallos Technologies, a UK-based company investing in security innovations.

“This implies that any defense against drones will soon be rendered obsolete as aggressors adapt.

“The aggressor,” he concludes, “will observe, adapt, and repeat – until they successfully penetrate.”}

So are we entirely focused on the wrong question? Instead of constructing a drone wall to counter the drones, should the focus not be on targeting the bases from which the drones are launched – as the age-old adage suggests, shoot the archer, not the arrow.

“It’s one thing to bolster resilience against it, but far more beneficial if the actions never occur at all,” contends Ms. Bego.

“And that fundamentally revolves around conveying to Russia, or whichever entity is responsible, that this type of behavior is unacceptable. It carries repercussions and entails costs for them. This is vital. It should genuinely be part of the discussion.”

However, any indication of NATO striking Russian targets – kinetically, rather than digitally in cyberspace – would present significant risks and heighten tensions.

Since Russia initiated its full-scale invasion of Ukraine on February 24, 2022, NATO’s challenge has been to assist Ukraine in self-defense while avoiding entanglement in a NATO-Russia conflict.

Constructing a defensive drone wall in Europe stands as one undertaking. Targeting the locations from which those drones are deployed is quite another.

Top picture credit: Getty Images, Sketchfab

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