[thackney]

Flying on Nuclear, The American Effort to Built a Nuclear Powered Bomber
http://www.aviation-history.com/articles/nuke-american.htm

After conversion, the engines were removed and a new configuration was incorporated. The NB-36 now had four GE J47 nuclear converted piston engines generating 3,800 hp augmented by four 23.13 kn turbojets generating 5,200 lbs of thrust. Each of the engines utilized the Direct-Cycle Configuration for power conversion. The NB-36 was designed from the beginning, to be propelled to the air with a conventional chemical mixture, and then the crew would switch on the reactor after achieving the necessary heat requirements on its core. On landing approaches, the aircraft would switch back to chemical mixture. This procedure was implemented in order to minimize the possibility of a major radiation leak in case of a crash landing.

The NB-36 made 47 recorded flights between the summer of 1955 and the fall of 1957. All these tests were made operating the NB-36 with conventional chemical power. The R-1 reactor was turned-on on many of these flights, not to actually power the aircraft, but to test and collect data on the feasibility of a sustained nuclear reaction on a moving platform.

Much more info at link

[BenLurkin]

Interesting!

[JoeFromSidney]

I worked on the guidance system for the proposed nuclear powered aircraft. No matter what design was proposed, the problem of shielding always killed it. Adequate shielding made the vehicle too heavy. Inadequate shielding brought problems, from neutron bombardment of the structure weakening it, to irradiation of the equipment (that was my concern), to irradiation of the crew. To illustrate the contortions the designers went through, one proposed design called for two vehicles: one would be a nuclear powered "tug," which would bring a conventionally powered bomber near the target, release it, and recover it later. The conventionally powered vehicle would be much faster than the "tug," and thus better able to penetrate enemy defenses. No matter how we sliced it, nuclear powered aircraft turned out to be a bad idea.