K-431 is a Soviet submarine that was part of the Soviet Navy during the Cold War. It was a Project 671 nuclear-powered attack submarine, designed for anti-submarine warfare and intelligence gathering. K-431 was notable for its advanced technology and capabilities, which were significant during its operational period. The submarine was commissioned in the early 1970s and served until the late 1990s. K-431 gained attention due to a tragic incident in 1983 when a fire broke out on board, resulting in the loss of several crew members. This event highlighted the risks associated with operating nuclear submarines.