K-278, the Soviet submarine that sank in 1989 taking with it two reactors and nuclear torpedoes

If you are wondering how many nuclear submarines have been sunk in combat, you should know that the answer is zero. This does not imply that several ships of this type are not found at the bottom of the sea, some of them in the company of the radioactive material that allowed them to function for long periods of time and even frighten their opponents.

Over time, nine nuclear submarines have sunk. Five from the USSR Navy, two from the Russian Navy and two from the US Navy. The protagonist of this article, the K-278 Komsomolets, arose as a project to improve the launch of missiles and ended up becoming a maritime tragedy.

The nuclear submarine that lies at the bottom of the Barents Sea

Towards the end of the 1960s, the Soviet Union had already built several nuclear submarines and was preparing to lay the foundations for what would become the Fourth generation of these strategic tools. The idea, according to defense specialist HI Suttonwas that the ships could carry and launch a combination of conventional and nuclear missiles.

To respond to that need, in 1966 a project known as “685” began to be developed, which contemplated the construction of a first advanced technology submarine as a prototype by the naval company Sevmash. This is how the K-278 Komsomolets arose, whose keel was laid in 1978 and launched into the sea in 1983.

The implemented features went beyond improvements to the level of weapons, but were also related to the versatility of attack and immersion. The helmet was made of titanium 48Tan alloy than steel, but strong enough to allow deep dives in combat scenarios.

The K-278 had been designed to operate at a routine depth of 800 meters, offering the possibility of reaching 1,000 meters in extreme situations. The collapse depth, that is, when the pressure on the hull is about to cause serious structural damage or an implosion, had been established at about 1,500 meters.

At the dimension level, it had a beam of 12.3 meters and a length of 110 meters. The propulsion system consisted of two jets OK-650 nuclear fission of pressurized water and uranium-235 fuel enriched to 20-45%. It was capable of launching conventional torpedoes and torpedoes with nuclear warheads.

The Norwegian Nuclear and Radiation Safety Authority (DSA) reports that on April 7, 1989, the K-278 was sailing in international waters of their country when its crew members detected fluctuations in the electrical system of the entire ship. The failures were the product of a fire in a compartment that compromised the operation of the reactors.

As a result of the aforementioned problem, the control mechanisms of the submarine began to behave erratically. Despite this chaotic situation, and with the smoke from the fire expanding inside, the ship managed to reach the surface and many crew members were rescued. Of the 69 sailors, 27 survived and 42 died.

The technological prodigy that promised to inaugurate a new class of submarines sank into the depths of the sea, taking with it two enriched uranium reactors and two torpedoes with nuclear warheads. Since then it lies more than 1,600 meters deep in the Barents Sea, on the edge of the Arctic Ocean, in Norway.

That episode, however, is far from being completely forgotten. Since then, Russia and Norway have been monitoring radiation levels in the accident area. In 2019, the Norwegian Marine Research Institute used the ROV Ægir 6000 to study in detail the remains of the Soviet-era submarine.

A series of samples taken that same year revealed that radiation levels in some parts of the ship were 800,000 times higher than normal. Other parts, they pointed out, “did not record such high values.” Although the aforementioned figures might seem alarming, the expedition leader, Hilde Elise Heldal, believed that they were not synonymous with danger.

Images: Norwegian Institute of Marine Research | DoD

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