The technology exists, and it is among the toppest of secrets. If you have a head for technical reading, you can have this patent: US20120105181A1. That is a rundown of the mathematics involved. You will also need to know about Radiatively Induced Fermion Resonance. Studying this secret relentlessly for years, I have found little bits of the puzzle. They are nuclear powered aircraft. They utilize a mercury-thorium solution as a fuel source and working fluid. Not a nuclear reactor, but a generator, directly converting the exploitable thorium beta decay chain, to a nuclear magnetic moment. The torus configuration is a self driving EM pump that then creates a force normal to gravity, like a super maglev. This is gimballed to achieve flight and maneuver. Many people have independently reversed this design, and the math is solid. I myself have collected documents to support every claim I just made. There is OPINT, SIGINT, HUMINT in there too. You dont see any Homer Hickam or North Korea types building them because they require literal tons of mercury, and the nuclear material. Mercury is very well controlled on a global scale, just like uranium, all kinds of environmental regulation.<p>The reason this tech will never be publicly released: they are flying nuclear hazmat nightmares. They put out an identifiable form of radiation when they operate. They can be detected, once you know how they run.<p>And we already have something better, there are rumors about newer ones with a better tech, but I dont quite understand the technical claims they make for how those work. Something about pulsed lasers and antimatter, the phrase Schwinger limit kept showing up.<p>Anyway, go buy an old Levitron off of Ebay, set it on your desk, any whenever you feel glum about the future, give it a spin and remember that its a hand powered UFO.