was a diesel-electric submarine
of the Soviet Navy
Her keel was laid down on 13 March 1950 at Krasnoye Sormovo
as a Project 613 unit (NATO
: ). She 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. She 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. She returned to sea in April 1959.
During the night of 26 January 1961, S-80
was operating in the Barents Sea
depth on her diesel engines. The ocean was at sea state
6 and air temperature was -5°C (23°F). At 01:27 on 27 January, the boat dropped below snorkel depth, which should have caused the automatic snorkel valve to shut, preventing water from entering the snorkel system. However, the de-icing system that should have warmed the valve with hot water from the diesel engines had been switched off, and the valve had become jammed with ice.
The diesel engines failed immediately as seawater flooded their air intakes. The machinist in the fifth compartment who discovered the flooding became confused by the complex array of valves, and did not shut the ventilation flapper valve quickly enough. By the time he located the... Read More