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I have decided not to pursue the construction of a vertical take off and horizontal flight system, so it seems reasonable to describe how a vertical take-off and fast horizontal system could be made. I posted some ideas on the uses of small systems six months ago under the title Quadcopter search and rescue system with multiple bases, based on a design for copters which I didn’t disclose fully. There are already some systems that do similar things, such as the United States Osprey, but that system can easily be superseded, because it uses an unnecessarily complicated system of rotating the wingtip mounted rotators while in flight. That system requires heavy and complicated mechanical systems and complicated balancing systems for maintaining control of the aircraft. These complex systems must work perfectly or the aircraft crashes. A much more reliable, more easily built  copterplane with faster horizontal flight can be built as follows.

Conceptually follow this: build a standard quadcopter, fly it to a comfortable altitude, then fly it horizontally to its top speed. Its speed and range are limited because the aircraft is being held aloft by its rotors, but if the rotors were mounted on wing tips with the wings at typical angle for horizontal flight, the wings would support the aircraft and all of the power used to lift the copter with rotors could be used for forward flight, so it would fly much faster. The vehicle described so far is rather like a quadcopter, but to convert it into an airplane it would need a tail assembly with vertical and horizontal control surfaces. These could have been built into our original conceptual vehicle and be part of the original copterplane from the takeoff position. The copter could have been sitting on the ground on its tail before takeoff. This copterplane could be built to any size from tiny to large passenger airplane.

There is an improvement that would increase its horizontal speed even more, and that is to make the wing rotors more powerful, and eliminate the equal size rotors that were mounted perpendicular to them as used in a quadcopter design. As just stated, without the two side rotors, the copter mode would lose stability. That stability could be regained by installing a smaller rotor on one side, usually called the top side when it is in horizontal flight. This copterplane would now look like an airplane, such as a DC-3, with a large tail assembly, but with large rotors on its wing tips, and a third engine with a rotor mounted above the fuselage. This third rotor is used for stability when in a vertical takeoff or landing mode of flight, but in airplane flight it wouldn’t be needed, so it could be shut down. It could be moved on its support rigging, like a cantilevered desk lamp, to the nose of the airplane and in this more symmetrical and streamlined position it could be used to add thrust to the forward flight. In vertical takeoff and landing, this third rotor’s engine would operate at a constant power and be used to control the aircraft by varying the pitch of the rotor. In this vertical mode the thrust of this third rotor could be directed from fully upward to fully downward, and would be used to maintain the stable vertical orientation of the aircraft. However, when shifted to airplane mode this rotor would not be used for flight control, but simply for forward thrust.

Describing this craft in words leaves a lot to the reader’s visual imagination, but when built this craft would be faster than other converta-planes because it is always delivering its power to the mode of operation, either vertical or horizontal. It is more efficient in both modes and therefore is better in both modes, and more aircraft weight can be given over to other needs, either more fuel for longer flying range, more ruggedness of the airplane itself, or more cargo capacity.

The copterplane would go much faster and further than a helicopter.

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