The K-278 Komsomolets, known by its NATO designation as the Mike-Class submarine, stands as a remarkable yet tragic chapter in Soviet naval history. This nuclear-powered attack submarine, part of Project 685 Plavnik, was designed for unprecedented deep-sea operations during the Cold War era. With its innovative titanium hull and record-breaking diving capabilities, the K-278 represented the pinnacle of Soviet engineering. 

The K-278’s short service life, however, ended abruptly on April 7, 1989, when it sank in the Norwegian Sea, claiming 42 lives—and raising ongoing environmental concerns due to its nuclear payload.

The K-278 Komsomolets was a one-of-a-kind vessel, developed by the Rubin Design Bureau to test technologies for future fourth-generation Russian nuclear submarines. Ordered in 1966 and designed by 1974, its keel was laid in 1978 at Severodvinsk, with launch in 1983 and commissioning on December 28, 1983. 

What set this Mike-Class submarine apart was its double-hull construction, featuring an inner hull made entirely of titanium for enhanced strength and corrosion resistance in deep waters. This gave the submarine the capacity to operate in far deeper waters than most of its Soviet and Western counterparts. On August 4, 1984, the K-278 achieved a world record by diving to 3,346 feet in the Norwegian Sea—far surpassing contemporary US submarines like the

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