Deyatelnyy (Russian: Деятельный, "Active") was a Soviet Navy 1135 Burevestnik-class Large Anti-Submarine Ship (Большой Противолодочный Корабль, BPK) or Krivak-class frigate. Displacing 3,200 tonnes (3,100 long tons; 3,500 short tons) full load, the vessel was built around the Metel anti-submarine missile system. Launched on 6 April 1975, Deyatelnyy served with the Black Sea Fleet and, as well as Bulgaria in the Black Sea, spent the next two decades travelling as far as the Mediterranean Sea to visit ports in North Africa for cultural reasons and to improve relations between the Soviet Union and other nations, For example, in 1981, the ship was the first Soviet vessel for more than ten years to visit Libya. In 1987, the vessel was used to test a new missile for the Metel system that added a