 In spite of a powerful turbojet, it could not rise more than four or five feet off the ground, i.e., out of ground effect.Thus, the Avrocar could be seen as a prototype for the early generations of hovercraft, lacking only a 'skirt' to make it a truly effective example of the type.Unmanned saucers have had more success; the Sikorsky Cypher is a saucer-like UAV which uses the disc-shaped shroud to protect rotor blades.