Twenty-four Kilo-class submarines were operated by the Soviet Union, of which eleven are still operated by Russia. One was sold to Poland, which remains operational, but another, sold to Romania, is no longer in service. Ten were sold to India; nine are still operational while the tenth caught fire and sank pierside in August 2013. Iran has three Kilos, and Algeria has two. China had two submarines, purchased after the end of the Cold War.
Unlike the United States Navy, which went all-in on nuclear power, Russia maintains fleets of both diesel and nuclear-powered submarines. A land power encompassing much of Eurasia, Russian submarines are based much closer to “the action” than American submarines are. While Russia maintains nuclear submarines for distant ocean patrols, its fleet of diesel submarines is more than adequate for conflicts in Europe, the Middle East and the Russian near abroad.
The mainstay of the Russian Navy’s conventionally powered fleet are Project 877–class submarines, known as the Kilo class to NATO and the West. Nicknamed the “Black Hole” submarine by the U.S. Navy, the Improved Kilos are extremely quiet. The class has been built more or less continuously for thirty years, a testament to their effectiveness at sea.
The Kilo class was originally meant to serve the navies of the Warsaw Pact countries, replacing older Whiskey- and Foxtrot-class boats. The sub measures just 238 feet long by thirty-two feet wide, and displace 3,076 tons submerged. The ship has a crew of just twelve officers and forty-one enlisted men, and has an endurance of forty-five days before needing to be resupplied.