David Axe


April 9, 2024

Small unmanned boats, packed with explosives and steered via satellite, are among the main weapons of Ukraine’s escalating naval campaign targeting the Russian Black Sea Fleet.

These boats have struck, and possibly sunk, three Russian warships—most recently, the missile-corvette Sergei Kotov outside the port of Feodosiya in southeastern Crimea on March 5.

If Ukraine’s unmanned surface vehicles, or USVs, have a flaw, it might be that their warheads—apparently weighing 400 or 500 pounds—are usually too small for one USV to sink a ship. Instead, the robot boats attack in packs, their operators aiming to score multiple hits.

It’s possible the Ukrainians are aiming to introduce a USV with a bigger standard warhead: an 1,100-pound monster reportedly taken from a decommissioned Styx anti-ship missile.

If so, Ukraine’s drone boat operators might have a new class of weapon on their hands—one that could sink ships and maybe also take out the spans of steel-and-concrete bridges, such as the strategic Kerch Bridge connecting Russia to Russian-occupied Crimea.

The first evidence of the possible new USV appeared last week when Romanian officials discovered an overturned rigid-hull inflatable boat in the Black Sea near Tuzla. A Romanian Maritime Rescue Service vessel towed the wreck to the port of Constanța, where government experts examined it on Wednesday.

According to Romanian media, the boat was fitted with a radio jammer. An explosive device—potentially the USV’s warhead—was found nearby. Weirdly, photos of the derelict USV seem to depict the warhead still attached to the vessel’s bow.

We don’t know for sure who the apparent drone boat belongs to or how it wound up in Romanian waters. Naval expert H.I. Sutton concluded the hull itself is a modification of an American-made search and rescue boat, copies of which Ukraine has received as aid. And the massive warhead comes from an old Styx anti-ship missile, which the Ukrainian navy once operated.

If Sutton is right about the technical details and the USV really is Ukrainian, it’s possible the Ukrainians are trying to add a veritable drone battleship to their fleet of drone destroyers: a maritime robot with serious firepower.

Why the Ukrainians would want a bigger USV is obvious. It’s standard practice for Ukrainian crews to deploy their drone vessels in packs of 10 or 12. It took 10 USVs to wreck the Russian landing ship Caesar Kunikov off of southern Crimea on Feb. 14.

“The battle lasted 20 minutes,” a Russian survivor recalled. “Four out of 10 naval drones were destroyed. The fifth drone hit Caesar Kunikov in the stern, thereby immobilizing the ship, after which drones six, seven, eight and nine hit the ship in turn on the left side in the area of the middle and closer to the stern, with the aim of overturning the ship.”

In theory, a USV with an 1,100-pound warhead could inflict as much damage as two USVs with 500-pound warheads—and render unnecessary the need to blast a hole in a ship’s hull with one USV and then steer another USV into that hole to destroy the ship’s machinery and hasten flooding.

Or the same bigger USV could target the pillars of the Kerch Bridge, just like a smaller Ukrainian USV did on July 17, 2023.

That earlier attack involved a USV that’s half the size of the boat the Romanians recovered but, according to CNN, still packed a huge 1,800-pound warhead. Maybe the Ukrainians are optimizing their bridge-attack drones by fitting a big warhead to a big hull.

Or maybe the drone is designed for one-hit sinkings of Russian ships.