|Fig. 1: U.S.S. Nautilus. George Washington Bridge, New York Harbor, 1956 (two years after being commissioned). Source: Wikimedia Commons|
Nuclear-based vehicles offer many advantages over more conventional hydrocarbon-burning engines. For instance, in contrast to hydrocarbon-based fuels, nuclear reactions do not consume oxygen. Likewise, the energy density of nuclear fuel is orders of magnitude greater than conventional hydrocarbon fuels, which drastically reduces the frequency required for refuelling.  These advantages are heavily leveraged in the military; nuclear powered submarines can go at ''full steam'' while submerged at arbitrary depths, without the need for a snorkel, as opposed to their diesel predecessors.  And submarines and aircraft carriers can run in excess of a decade without refuelling, giving them an effectively unlimited range. 
In 1954, less than a decade after the bombing of Hiroshima, the first nuclear submarine, the U.S.S. Nautilus, was commissioned (Fig. 1).  The Nautilus was an emphatic success; it saw more than half a million miles, and was the first submarine to complete travel from the Pacific to the Atlantic via the North Pole.  It now functions as a naval exhibit (Fig. 2). Nuclear power is also utilized for aircraft carriers; the first nuclear powered aircraft carrier, the U.S.S. Enterprise (commissioned 1961), is still in use as of this writing. It is powered by eight nuclear reactors.
|Fig. 2: U.S.S. Nautilus, in 2002. Source: Wikimedia Commons|
With such great strides being made in nuclear technology (from bomb to boat in less than a decade), nuclear propulsion did not seem limited to seagoing vehicles. The U.S. Air Force and Atomic Energy Commission fitted a Convair B-36 "Peacemaker" airplane (bomber) with a nuclear reactor. Although the nuclear reactor was functional, it was not intended to power the aircraft, but was used to test the feasibility of carrying a nuclear reactor in an aircraft. It made 47 test flights between 1955-1957.  There were many potential advantages to a nuclear aircraft; with such high energy density of fuels, it was conceivable that the planes could remain in air for much greater distances than allowed by conventional fuels; this was especially important before the advent of advanced ICBMs or satellites.
Applications of nuclear propulsion weren't just restricted to the military. In 1958, Ford introduced a model concept car, the Nucleon. [7,8] With its futuristic, Jetsons-esque looks (shielding from radiation being a serious design constraint), it would have offered incredible range had it been produced. Ultimately though, it was never more than a concept (it never contained a nuclear reactor).
© Brannon Klopfer. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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