K-222: The fastest submarine in the world

The Soviet nuclear submarine K-222 set a speed record more than 50 years ago and has never been beaten since.

Designed and built more than 50 years ago, the Soviet submarine K-222 still holds the record for the world's fastest submarine ever built, reaching speeds of 82.8 km/h, according to IFL Science . Originally named K-162, the K-222 was developed under the direction of the Central Committee of the Communist Party of the Soviet Union and the Council of Ministers in 1958 as part of an effort to create a new high-speed submarine. Built in the northern Soviet port city of Severodvinsk in the 1960s, the Project 661 submarine was delivered in 1969.

Nuclear-powered submarine K-222. (Photo: National Interest).

Armed with nuclear weapons and powered by nuclear energy, the submarine was just over 350 feet long and was one of the first submarines to have a titanium hull. However, its most notable feature was its speed. During testing in 1969, it was faster than expected, reaching 48 mph instead of 45 mph. It reached its highest speed during a test in 1971, reaching 52 mph at full nuclear power. That speed has never been surpassed since.

The K-222 seemed to pose a threat to the United States and other NATO allies during the Cold War, challenging their technical capabilities. Compared to it, one of the fastest submarines ever developed by the United States, the nuclear-powered attack submarine Seawolf, only reached a speed of 64 km/h.

However, the power of the submarine is difficult to maintain. The high speed puts stress on the structure. In addition, the system is very complex and expensive to operate. Inside the submarine's control room, noise can reach 100 decibels, almost as loud as a busy nightclub.

A decisive event for the project occurred in September 1980 when an accident occurred during maintenance work on the submarine's nuclear reactor. The submarine was finally decommissioned in 1988 before being scrapped in 2010. Due to the technical difficulties of the K-222, it is unlikely that any submarine will ever beat its speed record.