From memory: Back in the 1950s there was an obsession with all things atomic and so the idea (from Nazi Germany) resurfaced of an atomic powered aircraft and this was taken up by Convair as a variant of the B-36 bomber which was large enough to cary both a reacor and a 40 ton bombload (theorectically). The sole NB-36H, nicknamed the Crusader, would be the initial test aircraft for the reactor although it would NOT power the aircraft. That would be accomplished by 6x piston engines rated at 5200 hp each and an additional pair of J47 jets in pods underwing. The B-1 sodium reactor was loaded into the bomb bay but shileded from the crew by a mid-fuselage lead disc and the cockpit area was shielded separately with 11 tons of lead, rubber, and a water shield that weighted down the modified nose. The reacor had to be shielded to both protect the crew and to prevent interference with the instrumentation and automated weapon systems (8 turrets of 2x 20mm cannons). The first problem encountered was the massive weight gain by the reactor and shielding that brought the speed down to under 400 mph making the bomber a prime target for enemy interceptors. Although the range and endurance was supposed to be unlimited in theory, the exposure to reactor and heating issues meant that in reality it could only fly maybe several days to a week at a time before landing. Between 1955-57 it made 47 test flights with the reactor SOMETIMES on and then the reactor was pulled from the bay for analysis and reinstalled each time. This cost almost $500,000,000 during the life of the program and delayed construction of the X-5 test craft which would lead to the X-6 production war model. The idea of nuke bombers overflying cities was not popular either and a shoot-down or crash would be a disaster. So after testing, the original order for the X-5 was canceled and the entire program faded away as better jet tech came along that rendered the atomic powerplant idea obsolete. The NB-36H had several unique features: 10" thick reinforced glass in the cockpit, fuselage inlets for cooling the reactor, special red and blue side-striping and a radiation symbol on the tail to designate that it was nuclear, and addtional lead shielding around the reactor. The USAF was not happy that part of the reactor's job was diverted over to help lifting the additional weight of the shielding and reactor itself. Seemed self-defeating. The Soviets had a similar design. And the original idea came from 1945 Nazi Germany that envisioned nuclear power for power stations, weapons, nuclear powered subs, and nuclear powered aircraft, although their design was a hypersonic type bomber.

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