
February 24, 1968 the Soviet diesel-electric submarine
K-129 from the base in Kamchatka went on combat duty. It was equipped with torpedoes and submarine launch missiles with separable nuclear warheads. Its task was to change another submarine on duty, and to be on duty in the neutral waters of the Pacific for three months. In the case of an order to start a war, it was she who was to release all the warheads at the largest Pacific-US base.
On March 8, at the appointed time, she did not go out for another communication session. On the one hand, this was not a particular reason for panic, because many factors could prevent the transmission of a signal. But the signal never arrived.
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Somehow, the Americans learned about the tragedy before us. According to intelligence data, around the same dates, the American submarine Swordfish, which had severe plating damage, arrived at the Japanese port of Yokosuka. As a second possible option, the Americans discovered an explosion with a special hydroacoustic system, which seems to be underwater. And since the courses of all ships were miscalculated, and there was no one in this area, it means that only a submarine could be the cause, and she could only be Soviet. (This version is invalid)
Then the director of the Central Intelligence Agency (CIA),
Richard Helms, asked for an audience with the US president personally. He said that the Soviet submarine sank, and its board contains valuable ciphers, encryption algorithms, not to mention the submarine itself and its military armament. But knowing the ciphers, it will be possible to decrypt the intercepted correspondence for many years, and get a huge amount of information. Despite the huge risk, consent was obtained. The whole operation was complicated by the fact that the estimated depth was 5000-6000 meters - a huge distance from the surface, with a huge water pressure.

To implement the project turned to a major businessman and billionaire
Howard Hughes . At the same time, the newspapers launched information about a ship that sank in the 18th century, carrying a large batch of gold, which they were going to get. The work went on for many years, the project budget was estimated at $ 500 million (according to en.wiki $ 800 million), and finally in July 1974, the Glomar Explorer appeared in the drowning area, equipped with claws to lift the submarine to the surface. There was an order to raise the nose, because it was there that the encryption bay was supposed to be located, and accordingly all the necessary data.
After the climb, the specialists saw that this part of the boat was severely ruined by both an explosion and water pressure. So, according to information from tonnel.ru), the mattresses of the sailor beds were compressed to 40 centimeters in length. However, to their surprise, the researchers did not find either a cryptographic compartment or any valuable documents. All that remained for them was to analyze the obtained part of the submarine, in which no new technological solutions were applied. It was decided to lift the remaining parts, but this was interrupted by quite a funny story.
A man in Los Angeles, California, sold to one gangster group that there were some documents in the Hughes safe that cost millions of dollars. He received his considerable deposit, and in the meantime the group set out to obtain documents. But, this man showed ingenuity, and sold the same information to another gangster group. Which gave him a deposit, and went to extract documents. You guessed it, right? Such “Cards, money, two trunks” happened: while one group opened the safe, the second arrived at the same place, and was surprised to find the first group. The first group was surprised to see some group, and just in case opened fire. There arrived the journalists, the rescue service, the police, and many other interesting people. Somehow, in the resulting chaos, the contract between the US and Hughes floated out of the house of Hughes, and ended up in an open print run. Thus, when the motives and actions of the United States became known, it was already impossible to get the remaining parts of the boat, and the project had to be abandoned.

And now, the solution to the lack of a cryptographic compartment in the bow of the boat. The fact is that the commander of this boat was a tall man - 192 cm - and he did not fit on a standard bed in his cabin. His legs rested just in this compartment, and during the overhaul of the boat, he asked to move it somewhere else, after which the commander was finally able to straighten his legs.
On December 31, 1999, Boris Yeltsin transferred his powers to Putin, after which, at 0.30 am, he signed a decree awarding the postmarine crew of the K-129 submarine with the Order of Courage.
Source: Professor Saliy Vyacheslav Nikolaevich, Saratov State University, 2010.
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