Abstract: A lighter-than-air type vehicle comprising a frame-work and a series of inflatable lift bags secured to said framework. The lift bags inwardly contain heating elements and a gas, such as hydrogen or helium, in intimate contact with the heater elements. A source of power is coupled to the heater elements is such that the supply of electrical current, for example, to said elements can be varied as to increase or decrease the degree of inflation of the respective lift bags. Propulsion structure is affixed to the framework and preferably comprises a pair of oppositely revolving propellers which are independently controlled. A shroud and interior plate-like vanes surround the propellers and are constructed and powered to vary the air stream, as to direction, coming from the propeller area.