Reactors have been flown and made critical in flight, but never used to provide power for aircraft propulsion. The Soviets got the closest, but they abandoned it as well.
Recently Putin has revived a nuclear powered cruise missile design. Status is unknown publicly, but it is believed to have been set back by a major test failure and contamination event.
Today, one can imagine solving the crew shielding problem of these large, nuclear powered bomber concepts by simply eliminating the crew and foregoing most of the requisite shielding. Had that been possible at the time these concepts might have been deployed.
Recently Putin has revived a nuclear powered cruise missile design. Status is unknown publicly, but it is believed to have been set back by a major test failure and contamination event.
Today, one can imagine solving the crew shielding problem of these large, nuclear powered bomber concepts by simply eliminating the crew and foregoing most of the requisite shielding. Had that been possible at the time these concepts might have been deployed.