A hover car is a personal vehicle that flies at a constant altitude of up to a few meters (yards) above the ground and used for personal transportation in the same way a modern automobile is employed. The concept usually appears in science fiction. In science fiction, it is capable of elevating itself some distance from the ground through some repulsion technology, presumably exploiting some short range anti-gravity principle so as to eliminate most friction forces which act against conventional vehicles. Other works feature vehicles that hover by having magnetic plates lined along roads, operating in a similar principle to Maglev. The capability of hovering above the ground eliminates the need for tires, and unlike an air-cushion vehicle, it does not produce a dust cloud. The closest devices are the hovercraft, which elevates itself above a water or level hard surface using a cushion of air retained by a flexible skirt, and the hovertrain, which is a type of high-speed train that replaces conventional steel wheels with hovercraft lift pads, and the conventional railway bed with a paved road-like surface, known as the "track" or "guideway". Efforts to build air-cushion hover cars Air-cushion hover cars are hovercraft. In April 1958, Ford engineers demonstrated the Glide-air, a model of a wheelless vehicle that speeds on a thin film of air only 76.2 μm ( of an inch) above its table top roadbed. An article in Modern Mechanix quoted Andrew A. Kucher, Ford's vice president in charge of Engineering and Research noting "We look upon Glide-air as a new form of high-speed land transportation, probably in the field of rail surface travel, for fast trips of distances of up to about ". In 1959, Ford displayed a hovercraft concept car, the Ford Levacar Mach I. In August 1961, Popular Science reported on the Aeromobile 35B, an air-cushion vehicle (ACV) that was invented by William Bertelsen and was envisioned to revolutionise the transportation system, with personal hovering self-driving cars that could speed up to . Efforts to build MagLev hover cars Ford also displayed a concept car, LEVICAR. It was a one-person, small in a modern sense, car propelled by maglev. The car was designed to be levitated by magnets, and was intended to be developed for high-speed transportation systems. The Levicar was very light and when raised off its guide rail by the magnetic it only required a blower in the back