The advantage of nuclear power is, cheap energy that lasts for extended period of times. It is not necessarily designed for speed or any other benefit. Aircraft rely on speed and low weight in order to perform effectively. Placing a nuclear reactor in an aircraft undermines its potential. Sure the thing can fly for 30 days without stopping to refuel, but who wants that? Who needs that? The components that make up a nuclear reactor small enough to fit into an airframe would be very heavy. I wonder if it could get up off the ground? Sure, this is fantasy, science fiction, but a line should be drawn somewhere. Reading that only makes me groan.