A permanent watery grave.
by Robert FarleyKey point: She rests at a depth of 15,000 feet—too deep to make recovery practical.
The Bay of Biscay is one of the world’s great submarine graveyards. In late World War II, British and American aircraft sank nearly seventy German U-boats in the Bay, which joined a handful of Allied and German subs sunk in the region during World War I. On April 12, 1970, a Soviet submarine found the same resting place. Unlike the others, however, K-8 was propelled by two nuclear reactors, and carried four torpedoes tipped by nuclear warheads.
The Novembers (627):
The November (Type 627) class was the Soviet Union’s first effort at developing nuclear attack submarines. The 627s were rough contemporaries of the Skate and Skipjack class attack boats of the U.S. Navy (USN), although they were somewhat larger and generally less well-arranged. Displacing 4750 tons submerged, the thirteen 627s could make thirty knots and carry twenty torpedoes (launched from eight forward tubes). Visually, the 627s resembled a larger version of the Foxtrot class diesel-electric subs; the Soviets would not adopt a teardrop hull until the later Victor class. The Novembers were renowned in the submarine community for their noise; louder than any contemporary nuclear sub, and even preceding diesel-electric designs.The Novembers were initially designed with a strategic purpose in mind. The Soviets worked on a long-range nuclear armed torpedo (dubbed T-15), which could strike NATO naval bases from ranges of up to 40km. The torpedo was so large that each submarine could only carry a single weapon. However, increasingly effective Western anti-submarine technology quickly scotched the first mission. The Novembers were too loud to plausibly find their way into close enough proximity to a NATO port to ever actually fire a nuclear torpedo in wartime conditions.
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On April 8, K-8 suffered two fires, resulting in a shutdown of both nuclear reactors. The boat surfaced, and Captain Vsevolod Borisovich Bessonov ordered the crew to abandon ship. Eight crew members, trapped in compartments that were either flooded or burned out, died in the initial incident. Fortunately, a Soviet repair vessel arrived, and took K-8 under tow. However, bad weather made the recover operation a difficult prospect. Much of K-8’s crew reboarded the submarine, and for three days fought a life-and-death struggle to save the boat. Although details remain scarce, there apparently was no opportunity to safely remove the four nuclear torpedoes from K-8, and transfer them to the repair ship.
Unfortunately, the loss of power onboard and the difficult weather conditions were too much for the crew to overcome. On April 12, K-8 sank with some forty crew members aboard, coming to rest at a rough depth of 15,000 feet. The depth made any effort at recovering the submarine, and the nuclear torpedoes, impractical.
Read more at A Dead Russian Submarine Armed with Nuclear Torpedoes was Never Recovered