The US Navy LSV-2 Cutthroat is the largest unmanned submarine in existence. It is 33.83 m (111 ft) long, 3.05 m (10 ft) wide, and weighs 205 tonnes (451,950 lb). The experimental craft is a 1:4 (25%) scale model of the Navy's Virginia class attack submarine, which is currently under development. The unarmed Cutthroat is powered by a 2,250 kW (3,000 hp) electric motor, and acts as a platform to test stealth technologies being developed for the Virginia class ships. By comparison, the 3-man Alvin submersible, which was used to discover the wreck of the Titanic, weighs 17 tonnes and is only 7 m (23.3 ft) long.The LSV-2 operates on Lake Pend Oreille at the Acoustic Research Detachement in Bayview, Idaho, the Navy's stealth technology laboratory. It was named after a native Idaho trout by students at a local elementary school. It was built by Newport News Shipbuilding and General Dynamics Electric Boat, and launched in 2001.