air release and movement to the surface is coordinated by an observer in a support craft. A recent development is the deployment of so-called narco-submarines by South American drug smugglers to evade law enforcement detection. Although they occasionally deploy true submarines, most are self-propelled semi-submersibles, where a portion of the craft remains above water at all times. In September 2011, Colombian authorities seized a 16-meter-long submersible that could hold a crew of 5, costing about $2 million. The vessel belonged to FARC rebels and had the capacity to carry at least 7 tonnes of drugs. Polar operations 1903 – Simon Lake submarine Protector surfaced through ice off Newport, Rhode Island. 1930 – operated under ice near Spitsbergen. 1937 – Soviet submarine Krasnogvardeyets operated under ice in the Denmark Strait. 1941–45 – German U-boats operated under ice from the Barents Sea to the Laptev Sea. 1946 – used upward-beamed fathometer in Operation Nanook in the Davis Strait. 1946–47 – used under-ice sonar in Operation High Jump in the Antarctic. 1947 – used upward-beamed echo sounder under pack ice in the Chukchi Sea. 1948 – developed techniques for making vertical ascents and descents through polynyas in the Chukchi Sea. 1952 – used an expanded upward-beamed sounder array in the Beaufort Sea. 1957 – reached 87 degrees north near Spitsbergen. 3 August 1958 – Nautilus used an inertial navigation system to reach the North Pole. 17 March 1959 – surfaced through the ice at the north pole. 1960 – transited under ice over the shallow ( deep) Bering-Chukchi shelf. 1960 – transited the Northwest Passage under ice. 1962 – Soviet reached the north pole. 1970 – carried out an extensive undersea mapping survey of the Siberian continental shelf. 1971 – reached the North Pole. conducted three Polar Exercises: 1976 (with US actor Charlton Heston aboard); 1984 joint operations with ; and 1990 joint exercises with . 6 May 1986 – , and meet and surface together at the Geographic North Pole. First three-submarine surfacing at the Pole. 19 May 1987 – joined and at the North Pole. March 2007 – participated in the Joint US Navy/Royal Navy Ice Exercise 2007 (ICEX-2007) in the Arctic Ocean with the . March 2009 – took part in Ice Exercise 2009 to test submarine operability and war-fighting capability in Arctic conditions. Technology Buoyancy and trim All surface ships, as well as surfaced submarines, are in a positively