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An Entirely New Class of Aircraft Arrives
fergus07 writes "Austrian research company IAT21 has presented a new type of aircraft at the Paris Air Show, which has the potential to become aviation's first disruptive technology since the jet engine. Neither fixed wing nor rotor craft, the D-Dalus uses four mechanically-linked, contra-rotating, cylindrical turbines for its propulsion, and by altering the angle of the blades, it can launch vertically, hover perfectly still, move in any direction, and thrust upwards and hence 'glue down' upon landing, which it can easily do on the deck of a ship, or even a moving vehicle. It's also almost silent, has the dynamic stability to enter buildings, handles rough weather with ease, flies very long distances very quickly and can lift very heavy loads. It accordingly holds immense promise as a platform for personal flight, for military usage, search and rescue, and much more."
"I am now planning aerial machines devoid of sustaining planes, ailerons, propellers, and other external attachments, which will be capable of immense speeds"
"You should not be at all surprised, if some day you see me fly from New York to Colorado Springs in a contrivance which will resemble a gas stove and weigh as much. ... and could, if necessary enter and depart through a window."
"The flying machine of the future -- my flying machine -- will be heavier than air, but it will not be an airplane. It will have no wings. It will be substantial, solid, stable. You cannot have a stable airplane. The gyroscope can never be successfully applied to the airplane, for it would give a stability that would result in the machine being torn to pieces by the wind, just as the unprotected airplane on the ground is torn to pieces by a high wind. My flying machine will have neither wings nor propellers. You might see it on the ground and you would never guess that it was a flying machine. Yet it will be able to move at will through the air in any direction with perfect safety, at higher speeds than have yet been reached, regardless of weather and oblivious of 'holes in the air' or downward currents. It will ascend in such currents if desired. It can remain absolutely stationary in the air even in a wind for great length of time. Its lifting power will not depend upon any such delicate devices as the bird has to employ, but upon positive mechanical action."
-Nikola Tesla
I'm not so sure. Assuming this is a variation on the Voith Schneider Propeller, consider a configuration of the cylinder of propellers with all the airfoils parallel, and pointed in the direction of flight (so the direction of flight is perpendicular to the cylinder's axis). That's essentially just six stacked wings in an odd configuration, kind of like a triplane. If you have enough forward velocity to maintain lift, all you need to do is lock the airfoils in place. By changing the angle of attack on some of them you can emulate flaps, and increase the lift. The compact configuration of wings would have lots of drag, but you could add fixed wings on the outside to help.
I think this thing can glide.
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
It also sounds like a fuel hog. Helicopters are fuel hogs because the rotation of the blade is necessary to provide the lift as well as the thrust. Fixed wing setups have the advantage of getting the lift for cheap. I think if it has any potential it may be at replacing rotor aircraft. Not fixed wings. I don't foresee fuel prices going down in the future.
I like my dinosaurs feathery, and my pterosaurs hairy (or is it pycnofibery?)
I am unsure of how this design will handle an engine-out situation. A fixed-wing aircraft will have some glide ratio (9:1, 7:1, whatever) and a helicopter will autorotate. What happens with this design? It looks like it would just become a brick.
There is a reason that less than 1/5 of one percent of the US population are pilots. It's not easy, it requires a lot of work, and it's very expensive (40-50 hours in a cheap cessna at $100/hr plus ~$35-45/hr for an instructor). There are even less instrument rated pilots (about 200,000 less) who are certificated to fly in poor weather/visibility. The problem isn't the "autopilotable" part (flying along a route), it's weather, navigation, landing, emergency procedures. Most people simply won't do it, it's far easier to drive a car.
No, no hoax. In the water, this kind of propulsion works fine. In the air, however, the rotating speed needed to push against sufficient amounts of air to yield usable lift is insane, and so is the stress on the blades- so it is a question of fabricating it from the right material.
I can assure you; the very instant the right material for constructing this becomes accessible, it goes to mass production.
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
I believe the Westland Wasp http://en.wikipedia.org/wiki/Westland_Wasp uses negative collective pitch to enable the helicopter to stick to the deck until it able to be lashed to the deck. I think the Merlin also has that feature. Very useful in heavy seas.