||1 + 9
||270 kt. (310 mph)
||1,300 nm (1,500 miles)
||Ø 28’ 6” Ø13’
||Engine Motors (incl. gears)
||1,972 hp 2 x 1.140 hp
||325 lbs. 2 x 180 lbs.
||28” x 25“ x 17“ Ø 10” x 15”
Currently, helicopters are not well suited for high speeds and long travel distances. Significantly higher performances (speed, distance, pay load) require a lower air drag and weight, economically obtainable only with winged aircraft.
Conventional helicopters reach speeds of about 175 kt. (200 mph), limited by the reduced speed at the tip of the retreating rotor blade, creating air velocities not capable of providing the required lift forces. Counter-rotating coaxial rotors prevent the effect of declining lift forces, but are mechanically complex and heavy, increasing the air drag, costs, and fuel consumption significantly. Aircrafts with a tiltable propeller drive/wing system require rotor/propeller units with a very wide opera-ting range (speed, thrust), resulting in large, complex rotor/propeller drives which are not optimal for neither horizontal nor vertical flight. They are also not practical for the more economical conventional start and landing.
Advanced hydrostatic drives have the flexibility and very high power density required for the concept of the new High-Speed Helicopter. The rotor and propeller deliver here the thrust for vertical take-off and the transition. In the vertical phase the propeller points toward the landing pad and is slightly tilted sideways to counter the moment of the rotor. During horizontal flight and higher speeds, the short wings provide the lift forces and the tiltable propeller in the rear the thrust.
The concept allows for a smaller, simplified rotor, designed only for vertical take-off and low horizontal speeds. At higher speeds, the lifting forces of the wing increase and the rotor will be shut down, the blades brought into parallel position, and the whole rotor mechanism sub-merged into the fuselage. The sideways tilting of the propeller is dis-continued, but used to change the direction of flight. This reduces the air drag of the helicopter by up to 50%. A simple tail plane can be added if needed.
The aerodynamic drag of the helicopter achieves, considering the lower air drag of the new hydrostatic drive and smaller wings, nearly that of winged aircraft and its high speeds and travel distances. The noise level and comfort (vibrations) will also be significantly improved.
The 3-cylinder free-piston engine achieves significant improvements in specific power (kW/kg) and a reduction in flow pulsation, advantageous for operations without a larger accumulator. The weight is ca. 35% lower than that of a turboshaft engine and the lower fuel consumption reduces the weight of the fuel by nearly 50%. The weight is based on Titanium housings. (See table: Comparison – Combustion Engines)
U.S. Patent pending.
The pictures show the helicopter in cruise and Vertical Take-Off and Landing (VTOL) position. The drivetrain components are shown in scale.