From what i have gathered this is the HTRE-1. It was a nuclear reactor hat was designed to power a bomber in the cold war days. the technologist did not "take off" due to political reasons and some technical issues. later prototypes of this was flow in the NB-36, while it never powered the aircraft but was run during flight.
from what i can tell it was a molten salt reactor or liquid fluoride thorium reactor. I looked like some interesting technology that never reached it's full potential
