Now that’s a big plane

The idea of nuclear powered aircraft has been around since shortly after WWII. Since nuclear reactors of the time were massive items requiring many tons of shielding, any aircraft based on a nuclear powerplant would necessarily be fairly big. Additionally, a larger aircraft would provide greater distance from the reactor for the crew, using space as shielding to help reduce the radiation dose the crew would get.

A USAF brochure from 1951 presented a number of preliminary configurations for nuclear powered bombers. One of them, the N-1 design, was a half-million-pound plane with a span of 225 feet and a payload of only 10,000 pounds.  It would be capable of cruising at Mach 0.9 at 60,000 feet. Other designs were smaller with greater payload, but designed to fly at lower altitudes. The cost of high speed at very high altitude was extremely long wings with high sweep; the result was a plane that would have made the B-36 look like a pipsqueak.