Ukraine’s First Jam-Proof Drones Were Ungainly Triple-Stackers

Mar 03, 2025

A Russian fiber-optic drone prowling the front line.

Both Russia and Ukraine are building and deploying explosive first-person-view drones at a rate of millions of copies per country per year. But Ukraine has maintained a drone advantage for around a year now, because it fields effective radio-jammers—and Russia doesn’t. The jammers block the signals that connect most drones to their operators.

Most, but not all. There’s a whole other class of FPV drone that doesn’t even need radio. Instead, this type of drone sends and receives data via a miles-long spool of millimeters-thick fiber-optic cable. Which country can field the best fiber-optic drones, and fastest, should have the edge as Russia’s wider war on Ukraine grinds into its fourth year.

Desperate to blunt the Ukrainians’ drone advantage, the Russians leaned into fiber-optic technology and, in early January, turned the tables on the Ukrainians. On Jan. 5, a company of Ukrainian paratroopers attacked the village of Berdin, in western Russia’s Kursk Oblast. The Russian garrison met them with a swarm of fiber-optic drones—and defeated the attack, sowing the snowy fields around Berdin with the mangled bodies of dead paratroopers.

The Ukrainian Unmanned Systems Forces, the world’s first independent drone branch, is scrambling to develop countermeasures to the fiber-optic FPVs and, so far, is resorting to spotting the unspooling fibers from the air and following back to their operators—and then bombing them. Meanwhile, the USF is moving fast to catch up to and, it hopes, surpass Russia’s fiber-optic drone tech.

Ukrainian fiber-optic drones.

“We’re now on the third generation of these products,” a USF official explained in an official video. That’s three generations of tech in just as few months—a breakneck pace of development.

Any FPV drone has three critical components in addition to its basic airframe, motors and propellers: a warhead, a battery and a voluminous container for a spool of thin fiber-optic cable that might be 13 miles long.

The very first generation of Ukrainian FPV drone stacked each element—the warhead, battery and spool—on top of each other in an awkward pile. It should go without saying that the stack isn’t very aerodynamic. “We oppose three-story drones as they have low energy efficiency,” the USF official admitted.

The next two drone generations combined elements. One stuffed the warhead inside the spool. The other stuffed the battery inside the spool. Both of these combos are more aerodynamic than the triple-stack drone, but the battery-inside version is more modular: it’s easier to swap in different warhead types, such as shaped-charge warheads optimized for penetrating vehicle armor.

It’s worth noting that Russia has also settled on two-story fiber-optic drone models. At best, the Ukrainians have matched the Russians’ basic design. Now it’s incumbent on them “to surpass [the Russians] in both quantity and quality” of fiber-optic drones, the USF official stated.