Golf-class submarine

The Project 629, (Russian: проект–629, lit. "Projekt-629"), also known by the NATO reporting name of Golf class, were a class of the diesel electric powered ballistic missile submarines that served in the Soviet Navy. They were designed as six Zulu class submarines were successfully modified to carry and launch Scud missiles. All Golf boats had left Soviet service by 1990, and have since been disposed of. According to some sources at least one Golf-class submarine was operated by China, to test new SLBMs.
Class history.
Project 629 was started in the mid-1950s along with the D-2 missile system which it was to carry, and was based on the Foxtrot. Design task was assigned to OKB-16, one of the two predecessors (the other being SKB-143) of the Malachite Central Design Bureau, which would eventually become one of the three Soviet/Russian submarine design centers, along with Rubin Design Bureau and Lazurit Central Design Bureau ("Lazurit" is the Russian word for lazurite). The submarine was originally designed to carry three R-11FM ballistic missiles with a range of around 150 km. These were carried in three silos fitted in the rear of the large sail behind the bridge. They could only be fired with the submarine surfaced and the missile raised above the sail but the submarine could be underway at the time. Only the first three boats were equipped with these—the remaining ones were equipped with the longer range R-13 missiles.
The first boats were commissioned in 1958 and the last in 1962.
The boats were built at two shipyards — 16 in Severodvinsk and 7 in Komsomolsk-na-Amure in the Far East. An 8th in the Far East went to China. Fourteen were extensively modified in 1966–1972 and became known as 629As by the Soviet Navy and Golf IIs by NATO (the original version having been designated Golf I). The major change was the upgrade of the missile system to carry R-21 missiles which could be launched from inside their tubes with the submarine submerged and increased speed. In later years a few were converted to test new missiles and others had different conversions.
All boats had left Soviet service by 1990. In 1993, ten were sold to North Korea for scrap. According to some sources, the North Koreans are attempting to get these boats back into service.
An organization of defectors from North Korea, named In-Kook Yantai, published a report in 2016 entitled "North Korea's Nuclear and WMD Assessment". In that report, North Korean defector Kim Heung-kwang said a 3,500 ton nuclear-powered submarine, one of a pair, was due for launch before 2018. It was described as having four missile launch silos in the sail and is generally thought to refer to a re-powered Golf II class vessel.
In 1959 the project technology was sold to China which built a single modified example in 1966, which is still in service.
Project Azorian.
On March 8, 1968, northwest of Oahu in the Pacific Ocean the Golf II class submarine "K-129" sank due to an explosion brought on by unknown cause, the accident being registered by the SOSUS network. The entire crew of 98 was lost and the vessel sank with three ballistic nuclear missiles as well as two nuclear torpedoes. The United States recovered parts of the submarine in July 1974 from a depth of around 5 km, in an operation named Project Azorian.
Two nuclear submarines that had been facing retirement, and , were rebuilt and pressed into service as deep sea search vehicles. After "Halibut" discovered a sunken Soviet submarine containing at least one intact ballistic missile complete with nuclear warhead, Melvin Laird, United States Secretary of Defense under President Richard Nixon, approved Azorian. Six years later, 1560 nautical miles north of the Pearl Harbor, a mechanical claw descended to the bottom of the Pacific and, guided by computers on board the Glomar Explorer, clamped onto the mass of twisted, rusting steel and began slowly raising it to the surface. It is unknown for sure how successful the effort was, but the United States has admitted to recovering a portion of "K-129", which included six bodies of Soviet sailors that were buried at sea with full honors.