Underwater drone Sub Sea Baby: Ukraine reports Russian submarine sunk in Novorossiysk

According to the Security Service of Ukraine (SBU), a Russian submarine has been sunk in the port of Novorossiysk in a unique special operation – using an underwater drone. The boat hit was reportedly of the Varshavyanka type (Project 636.3, NATO: Improved Kilo II). The SBU is headed by Lieutenant General Vasyl Maliuk.

The operation was carried out jointly by the SBU’s 13th Main Directorate of Military Counterintelligence and the Ukrainian Navy.

Three variants of the underwater drone

A Ukrainian Sub Sea Baby underwater drone was used, about which little is known so far. The Ukrainian military journal Militarnyi names three versions developed: TLK 150, TLK 400 and TLK 1000.

The TLK 150 is said to be around 2.5 metres long; with a range of about 100 kilometres, it can reportedly carry a 20 to 50 kilogram warhead. For the TLK 400, a length of four to six metres is possible; its warhead may weigh up to 500 kilograms and be delivered over up to 1,200 kilometres. The TLK 1000, in turn, is said to be four to twelve metres long and able to carry a warhead of up to 5,000 kilograms. As early as June, Ukraine had used an underwater drone in an attack on a pillar of the Crimean Bridge.

The 13th Main Directorate of Military Counterintelligence of the Security Service of Ukraine is a special unit that has proven to be one of the country’s most effective military formations. It conducts its special operations far behind the front line – including attacks with naval drones and attacks with unmanned aerial vehicles (UAV) on enemy infrastructure.

Varshavyanka submarines are diesel-electric cruise missile carriers. The boats are around 74 metres long and displace about 3,950 tonnes submerged. Their diving depth reaches 300 metres, the crew numbers 52, and they can stay at sea for up to 45 days. They are armed with torpedoes and/or mines and up to four Kalibr cruise missiles.

The Security Service of Ukraine puts the current replacement value of such a boat at over 400 million euros. The submarine now hit is already the second of this class to have been at least severely damaged in Russia’s war of aggression against Ukraine. On 13 September 2023, the Ukrainian Armed Forces attacked dry docks in Sevastopol with Storm Shadow missiles, severely damaging the B-237 “Rostov-on-Don”.

Russia denies

The Russian side, by contrast, speaks not of a sunk submarine but of a failed operation. Captain (1st Rank) Alexei Rulyov, head of the press office of the Russian Black Sea Fleet, stated: “The information spread by Ukrainian intelligence services about the alleged ‘destruction’ of a Russian submarine in the bay of the Black Sea Fleet’s Novorossiysk naval base is not true”.

Rulyov also said: “The enemy’s attempt to carry out sabotage with an unmanned underwater vehicle did not achieve its goals. No ship or submarine of the Black Sea Fleet stationed in the bay of the Novorossiysk naval base, nor their crews, suffered damage from the sabotage, and they therefore continue their service in normal mode.”