A week of air disruptions in Denmark has mounted to an aggressive show of vulnerability, with new drone sightings made over several military bases. The Danish Defense Ministry ascertained activity at Skrydstrup Air Base, where F-35 and F-16 fighter aircraft are based, as well as the Jutland Dragoon Regiment, while West and Central Jutland police identified drones within and outside the perimeter of Karup Air Base, the nation’s largest defense facility and center for all the armed forces’ helicopters and airspace monitoring.
Prime Minister Mette Frederiksen alerted that Europe is waging a “hybrid war,” calling the incursions “the most serious attack on Danish critical infrastructure to date.” Justice Minister Peter Hummelgaard was direct about motive: “The goal of the flyovers is to sow fear and division.” The incidents have been attributed to a “professional actor,” although they have not named their suspect publicly.
The operational challenge is stark. None of the drones have been shot down, a choice based on safety. As Defense Chief Michael Hyldgaard put it, When you shoot something down in the air, something also comes down again. In urban or airport settings, remains from lithium battery packs or fuel cells can cause fires, which makes takedowns a risk-based decision. This caution contrasts sharply with Poland’s approach, where military units shot down about 20 Russian drones violating its airspace earlier this month.
The intrusions have led Denmark to accept Sweden’s offer to provide a military anti-drone capability before next week’s EU leaders’ summit in Copenhagen. Although details have not been made public, Sweden’s systems probably include radio-frequency detection arrays, electro-optical tracking, and kinetic or electronic countermeasures. Contemporary anti-drone platforms incorporate layered defenses: long-range radar for early warning, mid-range electro-optical sensors for identification, and close-range jamming or net-based capture systems.
Electronic warfare is at the heart of these countermeasures. RF jammers will destroy command-and-control communications between drone and operator, sending the UAV into a controlled descent or fail-safe mode. More sophisticated systems use GPS spoofing, presenting fake positional information to confuse the drone. But such countermeasures are ineffective against autonomous drones flying pre-programmed routes, an ability very much within the reach of state-sponsored actors.
The events have also intensified attention on the planned “drone wall” along the EU external borders. The proposal, explored by defence ministers from frontline nations and by NATO officials, involves a system of detection, tracking, and intercept assets covering land, sea, and space. Radar assets on the ground would be supported by naval patrol ships with anti-drone sensors, while space-based situational awareness systems might monitor UAV takeoff from several hundred kilometers away. The success of the wall depends on bringing together civil and military airspace surveillance, a gap highlighted by Denmark’s experience.
Suspicion has grown with a sighting of a Russian Ropucha-class landing ship, the Aleksandr Shabalin, hovering only 12 kilometers off the coast of the Danish island of Langeland amid the wave of Scandinavian drone sightings. The ship’s transponder was also turned off, violating sea convention and making it harder to track. Even though officials have not attributed the ship directly to the incursions, its proximity has raised speculation regarding sea-launched drone launches an operation that takes advantage of blind spots in sea coastal radar coverage.
The wider strategic issue is cost asymmetry. Using low-cost, small drones to buzz airports and military installations makes governments expend large sums on countermeasures, ranging from radar improvements to interceptor missiles, without inducing overt war. As EU Defense Commissioner Andrius Kubilius summarized, Russia is testing the EU and NATO. Our response must be firm, united, and immediate.
Denmark’s wake-up call is evident. Police have heightened their crisis level, and the government is speeding plans for an integrated layered air defense system. But as University of South Denmark’s Kjeld Jensen pointed out, “From an engineering perspective it’s so much easier to build a drone that can fly than to build something that can keep them from flying.” The problem now is to bridge that gap before the next wave of invasions.
