Patent ID: 7267299

Claim:
An aircraft comprising: a fuselage; a circular airfoil body, wherein the body is generally hollow and defined by an upper and lower surface, the upper surface comprising an upper disk and the lower surface comprising a lower disk; a vertical drive shaft mechanism supports the upper and lower disks above the fuselage and at a fixed spacing relative to one another, wherein the upper and lower disks are arranged to counter-rotate relative to one another; wherein the lower disk has a plurality of first openings and wherein the lower disk has a first plurality of vanes each supported in a respective one of said first openings, said first plurality of vanes are movable between a take off position and a cruising position; wherein in the take off position the first plurality of vanes are arranged for diverting air downwardly through the first openings, wherein in the cruising position the first plurality of vanes are continuous with the lower surface of the lower disk such that the each of the first plurality of vanes substantially fully span a respective one of said first openings; wherein the upper disk has a plurality of second openings and wherein the upper disk has a second plurality of vanes each supported in a respective one of said plurality of second openings, said second plurality of vanes are movable between a take off position and cruising position; wherein in the take off position the second plurality of vanes are arranged for diverting air downwardly through the second openings, wherein in the cruising position the second plurality of vanes are continuous with the upper surface of the upper disk such that each of the second plurality of vanes substantially fully span a respective one of said second openings.