April 10, 2024: In the Black Sea, Russia is still able to operate several submarines that can submerge to escape attack by Ukrainian armed USVs (Unmanned Surface Vessels) which have damaged or destroyed several Russian warships. Now Ukraine is about to receive a land-based weapon that can attack and destroy Russian submarines even if they are submerged. This is the new Swedish SLWT (Saab Lightweight Torpedo) or simply Torpedo 47, which entered service in 2022 with the Swedish and Finnish navies. It can be launched from ships, aircraft, helicopters, and land based coastal launchers.

Torpedo 47 is designed to operate most effectively in shallow coastal waters and is 2.85 meters long with a diameter of 400mm. That’s 16 inches, the standard dimension of lightweight torpedoes. Torpedo 47 weighs 340 kg and has a warhead containing 50 kg of explosives. It is powered by a lithium battery than enables the torpedo to move at up to 70 kilometers an hour against targets 20 to 50 kilometers away depending on the speed of the torpedo. Torpedo 47 can hit submarines at depths of more than 300 meters. Active (sonar) and passive (listening only) guidance systems are used.

Ukraine could use a helicopter or large UAV to carry and launch Torpedo 47, in addition to using a land-based launcher on a dock or an anchored offshore platform. Russia has four Kilo class submarines available in the Black Sea, operating from bases on the Crimean Peninsula. Kilos launch Kalibr land attack cruise missiles from their torpedo tubes while submerged. These missiles have a range of more than 1,500 kilometers and carry a warhead with 450 kg of explosives. Kalibr was based on the earlier American Tomahawk missile and proved to be about as capable as the earlier models of the Tomahawk. The Russian Kilos in the Black Sea have long been targets because those Kalibr missiles were used to attack targets in Ukraine.

There were six Kilos in the Black Sea when Russia invaded Ukraine in early 2022. Two of those were damaged or destroyed by missiles or air-delivered bombs within the first year of the war. Ukrainian armed USVs destroyed several Russian warships, and the rest of their Black Sea Fleet was moved to ports about a thousand kilometers from Crimea to protect them from more Ukrainian attacks. Russian ships and submarines can still launch Kalibr missiles at Ukrainian targets, but these missiles can be intercepted by Ukrainian anti-aircraft missile systems. These anti-aircraft systems only cover key portions of Ukraine. There are still plenty of less important targets in Ukraine lacking protection that the Kalibr missiles can hit. Russia is apparently saving its growing inventory of Kalibr missiles for a mass attack in the future that can overwhelm air defenses with numbers. Meanwhile the Ukrainian Torpedo 47 system will give the Kilo submarines something to worry about.