The following video explains some of the eye opening technologies the US government has developed in its black-op Skunk-works projects. The two main technologies are anti-gravity machines, and electrogravitic propulsion technology.
Combine those two technologies and you get the basic workings of a Black Project TR-3B.
Watch the video in full to get a basic understanding of how thesetechnologies work.
And below is an image of a recently photographed top-secret aircraft in Florida, so you know that these aircraft do infact exist.