Some people in these days still believe that nuclear planes will be the future. Here are  some  reasons against this chance. Building of nuclear planes stretches back into the 50s of the last century, when in the giant technological leap the US engineers spent over unbelievable 1 billion US dollars, to create the first nuclear powered airplane. They thought that 1 pound of nuclear material would counter their need of refueling. Unluckily the project got canceled, because the plane radioactivity will kill the passengers or the pilot, and this proves that nuclear powered planes are costing to much. Lets also think about how nuclear energy is made. Believe it or not 2,000 metric tones of highly radioactive waste and 12m cubic feet of low-level radioactive waste, in the US alone is produced by the nuclear fuel process! This pollution effects the global warming and the habitat of the earth. The most important element for the production of nuclear energy is uranium, which is an earth produced material. The Scientific American states that Nuclear Energy Agency (NEA) that the worlds  uranium supplies will run out in about 200 years, as they estimate. This means if the world would now start getting used to using the nuclear energy more by the time they are used to it  could run out, what would be trouble. Even the mining of uranium is hard enough, as the miners suffer lung diseases  such as lung cancer ,tuberculosis and more. And how save nuclear powered airplanes are? I think you remember the Chernobyl accident in 1986, that sent so many radioactive rays out? Imagine even the slightest accident creating so much trouble and in  the air, is what many critics think about. These potential catastrophes are one of the many problems on developing these planes. In 1930s they thought there will be nuclear powered airplanes in 50 years, nearly 100 years later we are still not there. 

Credits to the  Scientific American website.