High Quality Content by WIKIPEDIA articles! United States Naval reactor refers to nuclear reactors used by the United States Navy aboard certain ships to produce power for propulsion, electric power, catapulting airplanes in aircraft carriers, and a few more minor uses. Such Naval nuclear reactors have a complete power plant associated with them. All US Navy submarines and supercarriers built for the past couple of decades are nuclear-powered by such reactors. There are no commissioned conventional (non-nuclear) submarines or aircraft carriers left in the US Navy, since the last conventional carrier, USS Kitty Hawk, was decommissioned in May 2009. The US Navy had nine nuclear-powered cruisers with such reactors also, but they have since been decommissioned. Reactors are designed by a variety of contractors, then developed and tested at one of several government (Department of Energy)-owned and prime contractor-operated facilities. These facilities include Bettis Atomic Power Laboratory in West Mifflin, PA and its associated Naval Reactors Facility in Idaho, and Knolls Atomic Power Laboratory in Niskayuna, NY and its associated Kesselring site in West Milton, NY, all under the management of the office of Naval Reactors. Sometimes there were full-scale nuclear-powered prototype plants built at the Naval Reactors Facility, Kesselring, and Windsor Locks (in CT) to test the nuclear plants, which were operated for years to train nuclear-qualified sailors.