Seawolf

…nuclear submarines, the Nautilus and Seawolf, to test the two types, but problems (including leakage) in the Seawolf reactor led to the abandonment of the liquid-metal scheme. Later the navy also developed natural-circulation reactors. U.S. attack submarines (except for USS Narwhal, the natural-circulation prototype) are built with pressurized-water reactors, but…

…build only three Seawolf submarines: Seawolf (commissioned in 1997), Connecticut (commissioned in 1998), and Jimmy Carter (commissioned in 2005). Seawolf and Connecticut cost $3 billion to build, and Jimmy Carter cost $3.5 billion. By the time Jimmy Carter was commissioned, the navy had already transitioned to the smaller and cheaper…