To widely provide a special aircraft not requiring a powerful lift engine which has been essential for development of a vertical take-off and landing aircraft having both vertical flight ability and high speed level flight ability, and taking advantage of a merit of having the two flight abilities to the full extent.

In order to improve vertical flight ability (not a lifting force but a buoyant force) which tends to be insufficient in conventional vertical take-off and landing aircrafts, the use of helium gas or the like which is generally used in an airship is especially appropriate. Furthermore, a flexible type envelope (gas bag) system or the like made of a powerful rubber may be widely used instead of a fixed type leather bag body used in an airship in order to minimize air resistance so as to prevent a decrease in flight speed in horizontal flight.