Intended to take off vertically like a helicopter, the craft's rigid rotors could be stopped in mid-flight to act as X-shaped wings to provide additional lift during forward flight, as well as having more conventional wings.
Instead of generating lift by twisting its blades as more conventional helicopters do, the craft used compressed air expelled from its blades to generate a virtual wing surface. Computerized valves made sure the compressed air came from the correct edge of the rotor, the correct edge changing as the rotor rotated.
The X-wing may have been named after the fictional X-wing starfighter from the Star Wars movies.