Sky Fortress: Ukraine's low-cost secret weapon to shoot down Russian drones

Since the start of the Russian invasion of Ukraine in February 2022, drones have played a crucial role in the progression of the conflict. Both sides have used these modern warfare devices to carry out offensives against civilian infrastructure and strategic military targets.

Although the war has been ongoing for just over three years now, one of the most striking operations took place earlier this June, when Ukrainian forces managed to infiltrate Russian territory and attack some four air bases using camouflaged drones. The war strategy caused significant damage to the Russian bomber fleet, and was met a few days later with retaliation from Moscow.

Ukraine's secret weapon

In recent months, drone attacks have intensified markedly.

This Monday, Kiev reported that its air defenses managed to shoot down a total of 277 Iranian-made Shahed drones, in addition to neutralizing another 183 unmanned devices using electronic jamming systems. This was one of the largest drone strikes recorded since the beginning of the war, evidencing the growing reliance on such technology.

To achieve this, Ukraine used a secret weapon developed by two of its engineers, who hastily sought to improve drone detection and neutralization systems in the midst of the conflict.

According to the magazine Foreign Policy, the main difficulty that the armies of both countries have today to detect the devices is the location of these unmanned aerial devices, due to their small size, their low sound profile and the altitude at which they usually operate, which allows them to easily avoid conventional radars. However, Ukraine seems to have more figured out since 2023 than Putin's forces.

How the Sky Fortress works

Ukraine has deployed an extensive network throughout its territory of nearly 10,000 acoustic sensors capable of picking up the characteristic hum generated by drone propellers, which significantly improves its air defense capability. The system, known as the "Sky Fortress," provides real-time targeting information to mobile fire teams, enabling them to effectively neutralize unmanned aerial vehicles (UAVs) with minimal training and cost.

They use simple but effective technology: a microphone and cell phone mounted on a six-foot-tall pole to detect the sound of approaching drones. The data collected by these thousands of sensors is centralized and processed, then distributed to field units via iPads, triggering a rapid response to drone threats.

This approach allows operators, with just a few hours of training, to effectively shoot down UAVs with anti-aircraft guns.