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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.
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...
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.
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.
This shows the value of issuing press releases.
The company's web site is a small self-consciously slick flash site. It contains only a few short press releases about this and several other technologies, each with similarly outlandish world-changing claims and supposedly already built and working.
According to Google Maps, the corporate address on the web site points to what appears to be a private home in a fancy neighborhood in Linz.
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?
>How many aircraft have been swept off a deck of a carrier after landing? NONE! Gravity keeps them there.
Sorry to argue but the answer is not "NONE", it's PLENTY. Gravity's great, but have you ever really watched a ship move in heavy seas? 30+ degree rolls are not uncommon, and when big pitching motion is encountered, the deck can actually move out from underneath you at nearly 0g.
I work around a bunch of guys who test carrier-based rotorcraft for the US Navy, and I can tell you (from having watched more than a few of the horror-story videos from testing) that this is a very real risk.
Here's a prime example from real life.
http://www.youtube.com/watch?v=wZSc5T-iUO4
Sorry, but gravity didn't really do much to help here.
More short clips of ugly sea conditions:
http://www.youtube.com/watch?v=H4MbCu_YRM4
http://www.youtube.com/watch?v=v3Mwd-3Kf-4 (0:33 and on)
Sticking a helo to the deck in rolling seas is NOT a trivial business, and downthrust or some mechanical hold-down is essential. It's not such a big deal for a carrier which doesn't move all that much, but every US Navy destroyer which hosts helos includes a winch-down system of some kind. Some are employed at great personal risk to the sailor who must run out under a hovering helo on a deck that's rolling over 10 deg back and forth every few seconds, hook up a cable (with a huge static shock risk), and run back out of harm's way while the cable literally pulls the helo down to the deck into the right position and holds it there. Some are lock-down systems that grab a probe sticking down from the bottom of the helo. You can see that probe and lock system here:
http://www.youtube.com/watch?v=9wWF9hDgl7E
--Brandon / Split Infinity Music