Akula Class submarine (Project 971, Shchuka-B) is a nuclear-powered attack submarine (SSN) first deployed by the Soviet Navy in 1986. The class is also known under the name Bars (meaning "snow leopard"). There are four sub-classes or flights of Shchuka, consisting of the original seven Akula Is, commissioned between 1984 and 1990; six Improved Akulas, commissioned between 1991 and 2009; one Akula II, commissioned in 1995; and one Akula III, commissioned in 2001. The Russians call all of the submarines Shchuka-B, regardless of modifications.

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