Finally! I can prove we actually had a hover mower when I was in high school. It was orange and white, and really only sort of worked. Nobody ever believes me when I talk about the hover mower, but here's a company that's been making them for years!
Since it hovered, that fan blowing downwards to keep it hovering was pretty powerful, and every so often it would shoot out a bit of twig or other lawn debris and nail me in the ankles.