The CarterCopter Heliplane (CCH) hovers like a conventional rotorcraft by tilting the rotor aft and using forward thrust from one of the propellers to control torque. During hover, the thrust from the second propeller can be varied forward or rearward, and by countering that thrust with rotor tilt the resulting moment allows the aircraft to remain level over large C.G. shifts. As the CCH accelerates, both propellers gradually provide the same forward thrust. An automated control system regulates prop thrust to minimize pilot workload.

Once the CCH achieves a certain forward velocity, most of the lift has been transferred from the rotor to high aspect ratio wings designed for very efficient cruise. After the heliplane switches from helicopter mode to autogyro mode, the rotor is then slowed using our patented technology for stably slowing the rotor while traveling at high forward velocities. This keeps the advancing tip speed below Mach 0.9 even at speeds of up to 500 mph. Because rotational drag is a cubic function of rotor speed, slowing the rotor dramatically reduces drag. This, in conjunction with the small high aspect wings, enables CCH to achieve speeds and fuel efficiencies comparable to many fixed wing aircraft. The wings are small and do not require complex, heavy high lift devices because they do not have to produce sufficient lift until the aircraft speed is moving at over 150 mph. The wings and landing gear support store sufficient fuel for exceptional range.

When making a landing approach, the CCH is generally in autogyro mode, completely eliminating the possibility of "settling under power" in a vortex ring state. The ultra-high-inertia rotor also provides the CCH with up to three times greater emergency reaction time than helicopters when flying in the classic "dead-man zone." The high inertia rotor enables the CCH to safely land fully loaded without power.

Several other design innovations enable us to keep the CCH component weights to a minimum, which in turn enables us to scale the CCH up to the size of a C-130 transport. First, the rotor itself is extremely lightweight, even with substantial amounts of lead weight in the rotor tips to provide both high inertia and stability. The rotor is composed of lightweight carbon composite with a twistable unidirectional carbon spar that extends from tip to tip. There is no structural joint, and because the spar is twistable, the spindle housing, spindle, and bearings are eliminated. Our hub carries no centrifugal loads, which are instead borne by the spar. The rotor drive is sized for short durations and thus can be lighter since it is only used for relatively short takeoff, hover, and landing maneuvers.

Our props are built from composite material with a similar twistable spar that eliminates much of the weight associated with conventional props, resulting in a prop that weighs only one-third as much as similarly sized competing designs. A computerized prop pitch control system results in efficiencies of up to 94 percent through a wide range of speeds.

Our landing gear is a very efficient design that provides extreme energy absorbing capability at minimum component weight. The entire fuselage is constructed from very lightweight, high strength composite materials. All pressurized doors will use a patented locking connection that distributes structural loads uniformly across the doors, which dramatically reduces structural requirements and weight. All these weight saving design innovations will enable the CCH to be scaled up to a size and useful load greater than the C-130.

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