x planes

from “Nuclear-powered aircraft” (“Применение атомных двигателей в авиации”), published in 1957, by G. Nesterenko, A. Sobolev, and Yu. Sushkov.

Fig. 61: Atomic convertiplane of the future in Antarctica
Fig. 57: Possible variant of nuclear aircraft with reactor shared between engines and full radiation protection.
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(Kindly submitted by Mr Alexey Mahotkin - immense thanks.)