Invention:
The technology involves the design of a hybrid tilt propeller / tilt wing aircraft augmented with Active Flow Control (AFC). This proposed design enhances the aircraft's cruise efficiency and reduces high-power consumption during takeoff, without compromising on hover, vertical takeoff and landing (VTOL), and super-short takeoff and landing (SSTOL) capabilities. The control of pitch in hover using an active tail and the tilt wing augmented by AFC not only reduces the power needed for zero run takeoff or landing but it allows the elimination of the cyclic and the edge flight transition to cruise.
Background:
The big advantage of airplanes capable of vertical take-off and landing (VTOL) is that they do not need a runway. Since the tilt rotor concept such as the V-22 evolved from a helicopter that is also used for search and rescue missions, long duration hover is a requirement. However, the thrust needed to hover is an order of magnitude larger than the thrust used by airplanes during cruise, thus a large penalty is paid by requiring an airplane to do both. A tilt-rotor aircraft has a short range and takes relatively small payloads due to download (i.e. the force generated by flow from the rotors that impinge on the upper surface of the wing during hover) take-off (download), and due to its stubby wings (i.e. the low wing span is necessitated in hover when the entire weight of the plane is carried by the rotor shafts). It is also expensive to run because it uses the cyclic capability of the rotor for stability and control during hover and the edge-flow transition to airplane mode.
A hybrid tilt-wing/tilt-rotor airplane concept that is aided by active flow control, can take-off without a runway and climb at very steep angles. It may transport heavy loads or large number of passengers very effectively and cheaply. Its download is reduced by partial tilt and active flow control. Its wingspan is increased by adding an outboard tilted wing, and most importantly, an active gimbled tail that is effective in hover and low forward speeds can eliminate the need for the cyclic motion thus reduce the cost and complexity of operation.
Applications:
- Military aircrafts
- Civilian aircrafts
- Transportation
Advantages:
- Reduces power requirements of takeoff
- High cruising speed capabilities
- Ability to climb very steep angles
- More efficient
- Reduces cost
- Reduces complexity of operation
