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Studies In Ornithopters
weileong writes "This should be of especial interest to fans of Frank Herbert's Dune (or maybe only those who preferred House Atreides) - a genuine, flexible, flapping-capable winged aircraft (by which I don't mean passenger-carrying. Yet.) has been produced by the University of Toronto's Institute for Aerospace Studies and SRI International (Washington Post article, free reg required). Advantages include everything from low speed control to efficiency. Once these things really hit "real world" usage, the V-22 Osprey really HAS no reason to exist (and all the army personnel at risk of dying in one should rejoice)."
It's the Marines that use the Osprey, not the Army.
The Tao that can be spoken is not the one eternal Tao
No need for the V22? Hardly.
:oD
The V22 is _finally_ getting to the mature design stage. They removed the problems that killed people (mostly, no a/c is perfect) like the inability to handle the loss of ground effect under one rotor.
Now they have an a/c which can not only take off vertically (or very sharply with high load), fly at 400mph and carry a ton of stuff. For it's role it beats the shit out of any helicopter (fast enough to do the job more fuel efficient, heavier loads,) and and cargo plane (no need for a JATO unit, can't run a C5 off a carrier).
This new technology is (like the tilt rotor concept was) unproven, and requires a complex set of engineering decisions to be made to get it to fly safley (like the tilt rotor). In 20 years, with a few deaths, it might be great - but the tilt rotor is here now.
FWIW there is now a commercial version of the V22 in prototype, the BA commuter aircraft. Small enough to land on helipads, but fast enough for intercity (and in Europe) international work. There have also been plans for a gunship version of the V22, with a massive rotary cannon and the ability to fly very slow it's even going to make the A-10 look a bit lightweight
Beep beep.
Click a bit further ;-) home page and movie can be found here.
This article has a picture of the ornithopter:
Mentor Micro-Air Vehicle
Wow, it looks weird.
The Osprey's had trouble for a reason--it's horribly complex, and there's never been an aircraft like it before (outside the X-planes, that is). An aircraft that transitions from a conventional airplane to a would-be helicopter has a lot of control issues to work out.
The poster's theory that the ornithopter will somehow make this superfluous is a bit ludicrous. An ornithopter large enough to carry troops will likely be even more complex. Taking the output from a turbine engine and gearing it down to spin a prop is trivial--we've been doing it for decades. Even with the complicated transmissions and crosslinks and control systems on the V-22, it's still basically just a combinatinon and evolution of previous aircraft.
Taking output from a turbine and translating it to drive a piston is another matter. It can be done, of course, but entails much higher losses. The researcher says enormous amounts of energy are required for the small one, and it's, um, small.
The strength of the parts is another issue. Making wings and linkages that will drive them is going to be a challenge. As will performance after an engine failure.
Don't get me wrong, this is quite an achievement. For the unmanned aerial vehicle trade. I don't think we'll have the technology to make a troop transport, or even a one-man aircraft, out of an ornithopter for a long time.
Trying to foist this as a replacement for the Osprey is a bit ludicrous. Replacing a complicated aircraft with a more complicated one does not lend itself to safety or reliability, right out of the box.
> the V-22 Osprey really HAS no reason to exist
Ridiculous comparison, this technology is designed to build micro-drones while the Osprey is supposed to lift tons of armament and passengers !
http://www.transparency.org
Your argument is all and well, except that aircraft ARE virtually perfect- it's the ones that are NOT perfect that we hear about. Second, when an aircraft is NOT perfect, you're supposed to fix it. The contractor involved and the armed forces instead outright lied through their teeth and ignored the problems while soldiers continued to die. Lastly, the problems were far more extensive than just one issue with ground effect.
There have also been plans for a gunship version of the V22, with a massive rotary cannon and the ability to fly very slow it's even going to make the A-10 look a bit lightweight
One of the warthog's best features is its heavy armour- some jokingly call it the 'flying bathtub' because of the cockpit reenforcement. I believe most hydraulic and electrical systems are also heavily armoured. It takes more than just a plane to make an effective way to shoot at people. Nevermind that the V22 looks to be completely intolerant of failure in either engine- and as any pilot knows, twin engined planes have twice as many engine failures because, surprise, you've got two of 'em :-) I'd be curious to hear your thoughts on how someone would eject from the V22 without standing a good chance of being sliced to pieces.
As for the original poster's comment that this will replace the V22- I hardly see how. Ever notice that 'Ornithopters' in nature don't really exist above a dozen pounds or so? Sure, we had some big flying dinosaurs a while back, but even those weren't nearly big enough to weigh as much as a small plane.
Please help metamoderate.
A certain idiot who shall remain nameless left this out of his post...
Ornithopter.Net
I think these are the same UofT guys who built the smaller model mentioned in the article.
ornithopter.org
VTOL planes always seem to be plenty risky - the Harriers are also quite widely known for killing their pilots, aren't they?
Err, no. Harriers have an excellent safety record and an even better combat one. During the Falklands War, British pilots of the Royal Air Force and Royal Navy lost none of their Harriers to enemy aircraft (one was shot down by ground-based anti-aircraft fire) whilst managing to shoot down twenty Argentine aircraft - this despite the fact that the subsonic Harriers were matched up against supersonic opponents.
VIFFing (vectoring in forward flight), a strategy limited to the Harrier and other VTOL aircraft capable of redirecting their thrust mid-flight, is a favourite dog fight strategy of Harrier pilots. One minute you're on his tail, lining him up for a shot, then next minute the Harrier's no longer in front of you because its pilot has "jumped" vertically. And, by the time you've worked it all out, he's dropped back down behind you and is about to missile lock your aircraft.
Next time, do your research.
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
OK, how bout next time you do your research, too. A quick google search turned up this story from the LA Times (mirror here)
Quote from the story:
And before you go off about untrained or unskilled American pilots again, check the author's Q&A here, where he points out this: and this:The Harrier is not a safe aircraft. The RAF knows it, that is why they are part of the Joint Strike Fighter program. That program aims to create a VTOL aircraft without the problems of the Harrier.
Hi, read this article some time back:
Harriers - the Widowmaker (from the LA Times)
Some excerpts:
Far From Battlefield, Marines Lose One-Third of Harrier Fleet
The corps, pursuing its long-held dream of a unique flying force, pays a heavy price: 45 of its elite officers killed.
Many of the Harrier's ailments can be traced directly to its innovative vertical-thrust technology. But despite the investment of tax dollars, aircraft and pilots' lives, there is little evidence that the Harrier's noncombat deaths have been redeemed in any significant way on the battlefield
In the Persian Gulf War in 1991, the hot thrust-producing nozzles in the heart of the fuselage -- the devices that allow the Harrier to rise and balance in the air -- made the plane a magnet for heat-seeking missiles. Its loss rate was more than double that of the war's other leading U.S. combat jets. Five Harriers were shot down and two pilots died.
"It's the most vulnerable plane that's in service now," said Franklin C. "Chuck" Spinney, who evaluates tactical aircraft for the Pentagon.
Next time, do your research
I actually did, you'd be pleased to know.
Yes and no. Fatigue WAS a major issue in the early years of aviation, but now it is well understood. As long as you have a proper understanding of the material's properties and the stresses induced by the application, then you can design to forestall or eliminate fatigue cracking. Some materials (certain types of steel) actually have infinite fatigue resistance as long as the stresses are below a critical threshold. Stress cracks are not an issue where one can employ a combination of good design, good "life" testing, good operator training, and good inspection/maintenance procedures. I'm not saying that bad things can't happen, just that they are preventable.
Two wrongs don't make a right, but three lefts do.
Yeah - and the fact that "army personnel" could care less: the V-22 is flown by the Marines exclusively. And if one doesn't think there's a difference, head off to the bar nearest the local Marine base. I'm sure someone will provide enlightenment.
"As God is my witness, I thought turkeys could fly." A. Carlson