Russian Navy B-871 Alrosa is the only Kilo-class sub that uses a pump jet propulsion system instead of a conventional propeller

Russian submarine B-871 Alrosa is an diesel-electric Kilo-class submarine that joined the Soviet Fleet in 1990 and is active with the Russian Black Sea Fleet as of 2011.In June 2011 she took part in a NATO submarine rescue exercise, 'Bold Monarch 2011,' the first Russian submarine to do so.

Instead of a conventional propeller Alrosa uses a pump jet propulsion system.