The Soviet submarine S-80 sinks when its snorkel malfunctions, flooding the boat.
S-80 was a diesel-electric submarine of the Soviet Navy.
Its keel was laid down on 13 March 1950 at Krasnoye Sormovo as a Project 613 unit (NATO : Whiskey class). It was launched on 21 October, and delivered to Baku on the Caspian Sea on 1 November for tests, then transferred north via inland waterways in December. It was commissioned into the Northern Fleet on 2 December 1952, and operated there until mid-1957.
Beginning in July 1957, S-80 was overhauled at Severodvinsk and converted to Project 644 ("Whiskey Twin-Cylinder") guided missile submarine, by having launch tubes for two SS-N-3 Shaddock anti-ship missiles fitted externally. It returned to sea in April 1959.