I have been watching a lot of UFO/paranormal stuff and one of the interviewees stated something along the lines of the spaceships using the gravitational field to hover. This makes a lot of sense. If you could determine which “band” of gravitational pull you wanted to “sit” on, your round(best shape for this) ship can just float on or across it. This is similar to the satellites that are orbiting us. They are “sitting” on a gravitational band. That’s why they sometimes come crashing down. Orbit is nothing but gravitational pull.
I think the secret to offsetting gravity is air pressure. Have you ever done the “blow-across-the-paper” experiment? You take a strip of paper and blow across the TOP of it, and it rises. If a “ship” has air pressure changed (maybe by using a large fan), then it should rise.
You know why you won’t see jetsons-type vehicles in your lifetime? People are too stupid. Notice how many wrecks people get into with cars? Imagine if these were floating vehicles, piloted by the average stupid american. Free to float over anyplace, at any time, crash into buildings and each other. Probably racing each other or “playing chicken”. Reality show watchers. ‘Nuf said.