- Ukraine’s MoD claims an armed uncrewed underwater vehicle (UUV) disabled a Russian Kilo-class submarine in Novorossiysk—potentially the first successful attack of its kind
- The strike (reportedly using a “SubSea Baby” UUV) would show a major leap in Ukraine’s long-range reach, hitting a key Black Sea base about 500 km from Odessa
- If confirmed, it would be Ukraine’s second claimed strike on a Russian submarine, targeting a Kalibr-capable platform used in attacks on Ukraine
Ukraine’s Ministry of Defence (MoD) is claiming to have disabled a Russian Navy Kilo-class submarine using an armed uncrewed underwater vehicle (UUV), in what, if confirmed, would mark the first time such an attack has been successfully carried out.
Detailed in a series of social media posts on 15 December, the Ukrainian MoD said “underwater drones” had struck and disabled a Project 636.3 Varshavyanka/Kilo-class conventionally powered attack submarine (SSK) in the port of Novorossiysk.
The Kilo-class SSN is able to be equipped with Kalibr cruise missiles, a type that have been used to devastating effect against Ukrainian cities and sites of critical national infrastructure in 2025.
According to numerous Ukrainian defence sources, the operation was jointly conducted by the 13th Main Directorate of the SBU Military Counterintelligence and the Naval Forces of Ukraine.
The port of Novorossiysk has become the main naval base for Russia’s surface and subsurface fleets operating in the Black Sea, given that Sevastopol, located on the Crimean Peninsula, is closer to Ukraine’s long-range strike weapons.
Additional details of the secretive operation are scarce, but with around 500km between the Ukrainian port of Odessa and Novorossiysk, should the strike be confirmed it would represent a significant evolution in Ukraine’s ability to hit Russian assets.
Ukraine cited a UUV known as the SubSea Baby, potentially an evolution of the Sea Baby USV, as being used in the strike against the Kilo-class SSK.
The latest strike was added to Ukraine’s claimed tally of destroyed Russian equipment, with the SSK now the second submarine to have been damaged and potentially sunk by Ukrainian drones.
Previously, Ukraine said it had struck a Kilo class in a missile strike on the Sevastopol naval base in September 2023.
Ukraine’s naval forces have rapidly adopted USVs and UUVs against Russian naval assets, conducting operations against warships in port as well as claimed ‘ghost fleet’ shipping used to evade Western sanctions.
Kilo-class (Type 636) SSK
The Kilo-class is one of the most widely operated SSK in global use, having been designed by the Rubin Central Maritime Design Bureau in St Petersburg and first entering service in the early 1980s.
Around 73m in length, the Kilo class displaces around 3,000 tonnes when submerged and is able to operate a range of anti-ship, anti-air, and land attack munitions, including the Kalibr and Club cruise missiles, with domestically operated 3M14K/3M14T munitions achieving a range of up to 2,500km.
