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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."
It's an entirely different kind of flying, altogether.
And it will bring us world peace, end hunger and cure cancer.
This shows the value of issuing press releases.
The wikipedia page also has an animation showing how it works.
"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
Thirty years ago I was in the Propulsion & Thermodynamics group at Lockheed. One of the guys had a research project on spanwise rotor propulsion - his proof of concept used a beefed up cylindrical hair dryer rotor of the day. Yeah, you can get some net thrust, but at nowhere near the efficiency of conventional designs. There has to be a really strong reason to sacrifice all the extra fuel and weight and safety deficits when compared to better techniques. Perhaps there are niches where the tradeoffs are worth it, but that is not what I'd call "immense promise". Let's see what kind of thrust-to-weight, lift-to-drag, and thrust-specific-fuel-consumption their aircraft can produce first...
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's an entirely different kind of flying. :D
Is it April 1st, or just slashdot mods got bored?
As a pilot and an engineer... the sheer amount of bs in one article stymies the ability to say anything else!
Silent turbines? Do you know how a turbine works? Definitionally it moves amazing amounts of air (and fuel). Air movement = sound. It can't be silent.
It can "hover" into a building? Do you know how the threshold between "Hey we're just outside the window" and "oh now we're 2ft above the 3rd floor" and "yeah now our exhaust has nowhere to go" works?
It can "glue itself down to a deck of a ship"? How many aircraft have been swept off a deck of a carrier after landing? NONE! Gravity keeps them there. Sure, the engines can generate more than 1G of lift ... but if you need 2G to stick the aircraft to the ground... get a nice tether because you have one really expensive balloon!
Ridiculous.
Is it April 1?
E
Full disclosure: I am a licensed rotorcraft pilot. That means I fly helicopters. They don't have silent counter-rotating turbines (lol) and don't "stick to the deck."
Here's a marvellous 1930's ref. from Wikipedia...
http://books.google.com/books?id=xSgDAAAAMBAJ&pg=PA26&dq=Popular+Science+1931+plane&hl=en&ei=5r8JTaa6Ismr8AaNmb2iAQ&sa=X&oi=book_result&ct=result&resnum=8&ved=0CEAQ6AEwBzgU#v=onepage&q&f=true
So... not exactly new but probably controllable with modern computer avionics.
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.
Parachute?
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.
FYI: many planes these days from ultralights up to aircraft like the Cirrus SR22 which runs up to $500k have ballistic parachutes either standard or as an option. It's not a new concept to have a whole plane parachute and there are videos on youtube you can check out to see them working.
There's still a lot of debate over effectiveness. There aren't that many plane crashes, and even fewer crash that have ballistic parachutes, so data is limited. Also, a large number of general aviation accidents happen at low speed and low altitude, such as take off and landing. Unfortunately, this is exactly the place where ballistic parachutes are least effective. So, the jury is still out, but I'd personally rather have the chute, rather than not have it and be in a situation where it would have helped...
I didn't have to dig very hard -- at all -- to find this clip:
http://www.youtube.com/watch?v=50cpPAVoxJQ
4 Sheridan tanks airdropped by parachute from way, way more than 10 feet up.
Not a very heavy tank by the looks of things, but still . . .
Kid-proof tablet..