March 27, 2024: The Russian Black Sea fleet has disappeared from the Black Sea. Russian warships are still in the Black Sea and the Sea of Azov extension in the northeast, and the more distant naval base at Novorossiysk, but rarely move out of port, even for a few days. Current ships in the Black Sea Fleet include six guided missile cruisers, one corvette, seven diesel attack submarines, seven landing ships and dozens of High-speed landing craft. sea-going minesweepers, anti-saboteur boats, missile boats and anti-submarine ships.

What keeps these Russian Navy ships from going to sea is the very real threat of attack by Ukrainian USVs (Unmanned Surface Vehicles), also known as drones. There are several models, including Sea Baby (Malyuk in Ukrainian), Mother (Mamai), and MAGURA which means Maritime Autonomous Guard Unmanned Robotic Apparatus. Sea Baby and Mother were developed by the SBU (Ukrainian secret service) and the navy. They are used by the 385th Separate Brigade which specializes in naval warfare. MAGURA was developed by GUR (translated as, Main Intelligence Directorate project) and SpetsTechnoExport, a state-owned enterprise. At the end of 2023 SBU unveiled an updated Cossack Mamai with a claimed top speed of 100 kilometers an hour. Manufacture of these drones is done in underground production facilities to avoid Russian missile and guided bomb attacks.

Malyuk was used in the mid-2023 Kerch Bridge attack and was carrying 850 kg of explosives to inflict significant damage to the bridge. MAGURA carries 320 kg of explosives while Mamai carries 450 kg. These USVs are no longer used just for delivering explosives against a target, as they can also be used for reconnaissance when equipped with video cameras that broadcast what they see back to the USV operator. Some USVs have been armed with small rocket launchers. Malyuk has a range of over 700 kilometers, which means they are suitable for operations on the high seas. Endurance is about 60 hours, and top speed is over 70 kilometers an hour. MAGURA has similar characteristics. Mamai was used in the long range attack at the distant naval base at Novorossiysk on Russia’s Black Sea eastern coast, which is a thousand kilometers from Crimea.

Ukraine has been developing subsurface USVs and in early 2023 the first one, the Toloka2 TK-150 was introduced. This USV was 2.5 meters long and equipped with a sensor mast that remained above the surface for navigation and to identify targets. Toloka2 can also carry a small explosive warhead. More recently, Ukraine developed the larger Marichka subsurface USV that is 6 meters long and one meter in diameter. Ukraine has planned for a Western manufacturer to build and weaponize Ukrainian USVs.

Ukrainian USVs have been quite successful in attacking and sinking or disabling Russian navy ships. So far there have been twelve attacks which resulted in damage to 12 ships and the sinking of a cruiser, two small landing ships and one missile corvette. The longest range raids have been against targets in the Kerch Strait including the eighteen kilometer long Kerch Strait bridge, which has been repeatedly attacked by Ukrainian USVs. As of early 2024 the bridge is unusable and under repair. When repairs are finished, the Ukrainians will attack the bridge again. The Kerch Strait bridge is a vital supply line for Russian forces in the Crimean Peninsula. Sending supplies by sea is no longer practical because of the risk of attack by Ukrainian USVs. This leaves the Kerch Strait bridge and when that is out of commission, the only supply route is a road from Russia that is under observation by the Ukrainians, who can attack supply movements at any time.

Apparently the only effective protection from USV attacks is the installation of multiple 25mm or 30mm automatic cannon gun mounts that are automated and use advanced AI and sensors. The guns must be able to point downward towards waters close to the hull. This makes it possible for the autocannon to fire on UAVs that get very close to the ship. No one has installed such a system yet though the Russian Navy might be working on something like this.