SC-21 (United States)

SC-21 (United States)

SC-21 (Surface Combatant for the 21st century) was a program started in 1994 to design land attack ships for the United States Navy. A wide variety of designs were examined, including an arsenal ship with 500 cruise missiles, but eventually a "tumblehome" design of around 16,000 tons with two long-range guns and 128 missile tubes was selected as the DD-21, the Destroyer for the 21st century. However the program was cancelled in November 2001, with a cheaper version of the DD-21 emerging as the DD(X) or Zumwalt class destroyer. It was envisaged that the DD-21 hull would be used for a future air defense cruiser (CG-21), which evolved into the CG(X) program.