Most if these are “cheating” by utilising the ground effect to achieve higher lift. In other words, they can only go up vertically a few meters, where they “res

Most if these are “cheating” by utilising the ground effect to achieve higher lift. In other words, they can only go up vertically a few meters, where they “rest” on a cushion of air similar to a hovercraft. Most or all of these human powered helicopters can’t exit this ground effect and hence can’t fly arbitrarily high — even 50 meters (150 feet) would be essentially impossible with the current designs.