Western intelligence assessments indicate that a Russian Navy attack submarine has been rendered inoperable following a Ukrainian underwater drone strike at the Novorossiysk Naval Base, marking another setback for Russia’s Black Sea Fleet. If confirmed, this would be the first time a submarine has ever been hit with a drone strike.
According to the UK Ministry of Defence, Ukrainian security services conducted the attack overnight on December 14–15, using an uncrewed underwater system to strike the B-271 Kolpino, a Kilo-class diesel-electric attack submarine, while it was docked in port. The strike reportedly caused significant damage, leaving the submarine unable to deploy or sail under its own power.
In its latest intelligence update, the UK Ministry of Defence said open-source reporting as of December 18 showed the Kolpino still moored in the same position as at the time of the strike. Other Russian vessels were observed dispersing from Novorossiysk as a precaution against further Ukrainian attacks.
Video footage released following the incident showed several additional Russian warships docked nearby at the time of the strike. UK officials assessed that the presence of multiple vessels highlights the potential impact had Ukraine launched a broader, coordinated underwater drone attack.
The Kolpino had been used by Russian forces to conduct missile strikes against Ukrainian critical infrastructure and energy targets. Although primarily an attack submarine designed for torpedo operations, the vessel had been modified to carry Kalibr cruise missiles, expanding its strike role during the conflict.
This marks the second known instance of a Russian submarine being taken out of action by Ukrainian forces. In earlier attacks, Ukraine struck the Kilo-class submarine Rostov-on-Don, leaving it unable to return to operational service.
The UK Ministry of Defence said the successful penetration of Novorossiysk’s layered harbor defenses demonstrates Ukraine’s growing proficiency in maritime operations using uncrewed systems. These defenses include air defense systems, patrol vessels, counter-drone nets and other protective measures designed to safeguard high-value naval assets.
Since the start of Russia’s invasion of Ukraine, the Russian Navy has lost more than 20 vessels, including warships, submarines, landing ships, patrol boats and support vessels. Among the losses is the guided-missile cruiser Moskva, formerly the flagship of the Black Sea Fleet.
British officials assessed that continued Ukrainian maritime drone operations are likely to further undermine Russian confidence in the Black Sea Fleet’s force protection measures, as Kyiv continues to contest Russian naval dominance despite lacking a large conventional surface fleet.
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Post Image – Kolpino submarine, Russian Black Sea Fleet, Sevastopol (Post Image Credit: Andrey Brichevsky)
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