The Royal Air Force’s experiments with drone swarms show they can overwhelm enemy defenses.

According to the U.K. military service’s chief of staff, this concept will be ready for hostilities.

British Chief of the Air Staff Sir Mike Wigston stated that the RAF’s 216 Test and Evaluation Squadron and the Rapid Capabilities Office had tested five types of drones in 13 experiments over three years.

According to him, this work yielded enough insights for the service to declare an “operationally useful and relevant capability” using its current fleet of drones.

The problem of overcoming enemy air defenses is a key obstacle to employing military power from above.

Planning for air operations is associated with planes’ safe flying increase. That puts at risk huge amounts of money that european governments invested in strengthening their fleets to fourth- and fifth-generation technology.

According to Justin Bronk, a defense analyst of the London-based Royal United Services Institute, this puzzle is visible in Ukraine, where Ukrainian and Russian air-defense capabilities are effectively canceling out the other side’s air power arsenal.

That’s because both Russian and Ukrainian militaries are ultimately dependent on massive land manpower and artillery, whereas joint forces of the U.K. and other western powers are critically dependent on having air access and air superiority.

Swarming, which means throwing enough expendable drones at a defensive radar and interceptor position so as to overwhelm them, can be effective, but only to a point.

The idea of small and cheap drones attacking air defenses by way of swarming may not be feasible because those drones lack the requisite range and speed.

“If you want things to go fast and far, they’re going to be jet-propelled and they’re going to cost a fair bit,” Bronk said.

In addition, getting drones swarms close enough to sophisticated air defenses with a range of hundreds of kilometers requires risky and potentially pricy insertion tactics that negate the widely cited cost benefit of cheap, small drones.