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Another Ornithopter Takes Off

CmdrTaco posted about 8 years ago | from the only-way-to-not-travel dept.

166

mnmn writes "Ornithopters have been around for a while, but a professor at the Toronto Institute for Aerospace Studies has made progress with his. It flew for 14 seconds and covered a third of a kilometer. However it landed with a bit of a crash. Interestingly it uses a glow jet turbine from RC aircraft."

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166 comments

A Glow Jet Turbine? (5, Interesting)

Mindwarp (15738) | about 8 years ago | (#15686880)

As far as I was aware model jet turbines run on Kerosene, just like their bigger brethren. Glow fuel is Nitromethane mixed with a lubricant such as Castor or Synthetic oil.

Re:A Glow Jet Turbine? (4, Interesting)

bev_tech_rob (313485) | about 8 years ago | (#15686895)

Ducted fan, maybe?

Den-tist! Jugga jigga wugga! Deli-style! Jugga jigga wugga!

Re:A Glow Jet Turbine? (4, Insightful)

Mindwarp (15738) | about 8 years ago | (#15686900)

Yeah, a ducted fan would definitely be driven by a two-stroke glow powered engine, but there's no way that it would generate the thrust needed for that application. They're a lot less powerful than a true jet turbine.

Re:A Glow Jet Turbine? (1)

TubeSteak (669689) | about 8 years ago | (#15687708)

Either way, TFA only mentions an engine with 60lbs (27 kilos) of thrust.
The plane weighs 276 kilos = 608 lbs

What I don't get is why he needs $100k worth of bigger wings to makeup for the 60lbs (27 kilos) of thrust provided by that engine.

Re:A Glow Jet Turbine? (0)

Anonymous Coward | about 8 years ago | (#15688064)

"The plane weighs 276 kilos = 608 lbs"

Kilograms is a unit of mass not weight (or force). Kilogram-force, on the other hand....

I know, everyone likes a little ass but nobody likes a smart-ass.

Re:A Glow Jet Turbine? (1)

WilliamSChips (793741) | about 8 years ago | (#15687133)

I come for the "Jugga"s but I stay for the "jigga wugga"s.

Re:A Glow Jet Turbine? (4, Informative)

jcr (53032) | about 8 years ago | (#15687008)

Glow fuel is Nitromethane mixed with a lubricant such as Castor or Synthetic oil.

Actually, it's a nitro/alcohol mix, with the nitro being anywhere from 5% to 50% or more.

-jcr

Re:A Glow Jet Turbine? (1)

rossifer (581396) | about 8 years ago | (#15687606)

Actually, "Nitromethanol" or "Nitrometh" is "a nitro/alcohol mix". You'll have to pardon the gp's misspelling of that as "Nitromethane". We knew what he meant.

Regards,
Ross

Re:A Glow Jet Turbine? (4, Informative)

jcr (53032) | about 8 years ago | (#15687964)

No, nitromethane [wikipedia.org] is mixed with methanol [wikipedia.org] and lubricants to make model airplane (glow) fuel.

-jcr

Re:A Glow Jet Turbine? (5, Informative)

Deadstick (535032) | about 8 years ago | (#15687018)

Actually, glow fuel is mostly methanol with some nitromethane added to improve ignition and horsepower, plus the lubricant you mention. The nitromethane content is typically 5-20%, though it was practically zero for about a year after a 1991 explosion that took out one of only two plants that make it in the US.

There are jet models using ducted fans powered by glow-plug engines, but it's a pretty kludgey solution, because it takes very high rpm and power levels for piston engines. The engines have aft-mounted exhaust ports so they can run a tuned pipe down the middle of the "jet" exhaust, and the pipe is tuned for an rpm just a little bit south of disintegration. They perform very impressively, but the noise is extremely obnoxious and excludes them from a lot of flying sites.

True turbojets began to appear in the Seventies and are common now. The big hurdle in making turbojets (or any gas turbine engine) is that you have to make the turbine wheel out of some exotic, hard-to-fabricate materials; the designers got over that one by adapting automotive turbocharger parts. They sound remarkably quiet, partially because a lot of the sound is above human hearing...your dog's mileage may vary.

rj

Re:A Glow Jet Turbine? (0)

Anonymous Coward | about 8 years ago | (#15687048)

>There are jet models using ducted fans powered by glow-plug engines, but it's a pretty kludgey solution, because it >takes very high rpm and power levels for piston engines

This sounds like an ideal application for a wankel rotary :)

Re:A Glow Jet Turbine? (4, Interesting)

dunkelfalke (91624) | about 8 years ago | (#15687238)

there is (no shit) a small helicopter powered by a lada (yes, that really bad russian car maker) wankel engine.
read more here [airliners.net]

Re:A Glow Jet Turbine? (1)

toxcspdrmn (471013) | about 8 years ago | (#15687984)

Not a Wankel, a radial piston engine. Completely different animal.

Glow fuel, glow fuel or maybe glow fuel (4, Funny)

beaverfever (584714) | about 8 years ago | (#15687449)

There are three posts describing what glow fuel is, they are all somewhat different, and they are all modded to 4 or 5 points as either informative or insightful. Who [uoguelph.ca] is the [modeltechnics.com] winner [easyrc.com] ?

And is this post funny, insighful, informative, or is it just off topic?

Re:A Glow Jet Turbine? (1)

qbwiz (87077) | about 8 years ago | (#15687654)

Actually, AFAIK a significant fraction (all?) of the jet engines that are used in model planes use only the compressor from a turbocharger. They want an axial turbine, so they have to make that from a fancy material like Inconel (or possibly good stainless steel).

At last (3, Funny)

Centurix (249778) | about 8 years ago | (#15686881)

Someone flapping about something worthwhile!

Re:At last (1)

Skyhawkelite (874245) | about 8 years ago | (#15688246)

I work at DRDC (defence research for Canada). My office area has a window that overlooks the hangar in Downsview Park. I saw the Ornithopter flap its wings. That thing is a total joke (it looks hilarious)....barely took off. You can walk over to the Hangar and actually see it.

Another roflcopter takes off (-1, Offtopic)

alveraan (945484) | about 8 years ago | (#15686896)

In other news, another roflcopter [funfreepages.com] takes off...

Ah.... (1)

deesine (722173) | about 8 years ago | (#15687067)

Makes me think of the old game Ladder, platform jumper using all ascii. Played that one on a Kaypro.

Can't wait!!! (3, Funny)

rangeva (471089) | about 8 years ago | (#15686899)

Cool!!! Can't wait for those charter flights to America on Boing Ornithopters... I wonder what kind of drinks they offer...

Re:Can't wait!!! (5, Funny)

Mindwarp (15738) | about 8 years ago | (#15686909)

I wonder what kind of drinks they offer...

Shakes.

Re:Can't wait!!! (1, Redundant)

praedictus (61731) | about 8 years ago | (#15686920)

I wonder what kind of drinks they offer... Shakes. And on British Airways, vodka martinis, shaken, not stirred.

Re:Can't wait!!! (1)

RMB2 (936187) | about 8 years ago | (#15687354)

Shakes on a plane

Re:Can't wait!!! (1)

jheath314 (916607) | about 8 years ago | (#15687250)

I suppose airlines might attract customers to either ornithopter flights by offering a "Big Dipper" discount...

Re:Can't wait!!! (1)

xs650 (741277) | about 8 years ago | (#15687495)

Well shaken.

birds (4, Insightful)

stocke2 (600251) | about 8 years ago | (#15686908)

I wonder if one problem is birds wings, while they do flap, they do not have a rigid shape, they change shape durring flight.
I wonder if an ornithopter could work with a wing that could change it shape slightly.
of course I am still not sure, is there an advantage to an ornithopter or is it just a curiosity thing?

Re:birds (2, Informative)

Sowelu (713889) | about 8 years ago | (#15686933)

As far as I can tell, the main advantage of an ornithopter--the reason that birds use that design--is that it doesn't require spinning parts, and it doesn't require literally burning fuel ie high temperatures. Living creatures don't spin very well or very fast and have no ball bearings, so living propellors would be out of the question, and throwing away some of your own mass isn't a good survival strategy, plus high temperatures have all kinds of problems. Bird wings are very useful if you don't have metal or oil, but past that? Probably no advantage at all.

Re:birds (4, Interesting)

Deadstick (535032) | about 8 years ago | (#15687060)

Precisely. We already have flapping-wing aircraft, and they fly much more efficiently than birds because we know how to make a rotating joint and nature doesn't. Consequently we flap with economical rotary [npr.org] motion instead of energy-wasting reciprocating motion.

rj

Re:birds (0)

Anonymous Coward | about 8 years ago | (#15687483)

"and they fly much more efficiently than birds"

Somehow I don't think so. This is what you'd call hubris.

Re:birds (1)

Deadstick (535032) | about 8 years ago | (#15687810)

This is what you'd call mathematics, but if you have a different take on the relative power-to-weight ratios of birds and helicopters I'm listening.

rj

Re:birds (0)

Khyber (864651) | about 8 years ago | (#15687641)

Nature doesn't make a rotating joint? Isn't your shoulder joint, a ball-and-socket joint, a rotating joint? I don't see how I could move my arm 360 degrees if I couldn't rotate it.

Re:birds (1)

Deadstick (535032) | about 8 years ago | (#15687803)

No, it's not a rotating joint. It's a bending joint, and you can't rotate your arm 360 degrees in any axis without also rotating it in another axis.

Hold an umbrella over your head, keep a firm grip on the handle, and see how far you can rotate it on its axis.

rj

Re:birds (1)

njh (24312) | about 8 years ago | (#15688247)

Actually, I can rotate my shoulder in a double figure of eight (spin 1/2) or around in a 'windmill' (as per backstroke swimming). I wonder whether either of those motions would make a good propellor. The joint doesn't need to move fast, if we have big blades. I suspect the main reason biology doesn't have such schemes is that it is hard to evolve them from something else useful.

Re:birds (3, Interesting)

falcon5768 (629591) | about 8 years ago | (#15688256)

actually you COULD rotate it 360, its not the joint that screws up the motion, its the muscles needed to create the motion. Nature makes rotating joints all over the place, its just its kinda useless thanks to the need to have something to move the joints. What would be more accurate is nature blows at creating gears.

Economy? (0)

Anonymous Coward | about 8 years ago | (#15687783)

The difference between flapping birds and rotary winged aircraft is fundamental. Don't get the two confused.
Fixed and rotary winged aircraft are built the way they are because it is easy, not because it is the most efficient. Don't confuse those either.
If you had actually RTFWikipediaA, you would know that birds' flight is actually more energy efficient than aircraft. Don't confuse practicality with perfection.

Boeing might disagree (2, Interesting)

bill_mcgonigle (4333) | about 8 years ago | (#15687968)

Precisely. We already have flapping-wing aircraft, and they fly much more efficiently than birds because we know how to make a rotating joint and nature doesn't. Consequently we flap with economical rotary motion instead of energy-wasting reciprocating motion.

There's a project [psu.edu] at Boeing to create a hummingbird-like propulsion system. It says, "Flapping flight may be the wave of the future for aviation." Their system relies on a shape-memory-metal actuator muscle. I'm forgetting at the moment who but there was another group recently that had a big announcement about simulating muscle with shape memory metal systems.

Obviously this is still R&D, but flapping doesn't seem to be down and out just yet. (BTW, I looked it up and a hummingbird wing is just shy of 180 degree rotation with 75% of the lift from the downstroke and 25% of the lift from the upstroke). Energy consumption is high, so portable fusion generators might be a necessary prerequisite for heavy craft.

Re:birds (0)

Anonymous Coward | about 8 years ago | (#15688136)

That's rotary motion, not rotating motion. And you're right only at the macro scale; many bacteria move by means of rotating flagella [nih.gov] .

Re:birds (0)

Anonymous Coward | about 8 years ago | (#15687359)

According to the wiki, an ornithopter is more efficient than both jet and propeller propulsion.

Solid Wing? (1)

camperdave (969942) | about 8 years ago | (#15687990)

I have seen videos of this beast before, and the one thing I do not understand is why does this have a solid wing? On the downstroke, a bird's feathers lock together to prevent the air from getting through, resulting in a large surface. On the upstroke, the feathers twist open to let the air through the wing, effectively cutting down on the wing surface. The feathers act like a one way valve.

This plane, though, has a solid wing. On the downstroke, the plane will get pushed up, but on the upstroke, the plane will be pushed down by the same amount. The thing would fly a lot better if they put a bunch of (if you'll pardon the pun) flapper valves along the surface of the wing.

Re:birds (3, Informative)

cgenman (325138) | about 8 years ago | (#15688227)

It had been said for many years that bees to not posess large enough wings to fly, and therefore they don't.

Recently, it was discovered that the bending of the bees' wings helped to create and pull vortecies of air from the base of the wings out to the tips, tripling the effective lift for the same surface area.

My guess is you're quite correct... until we move to a soft-wing design, we're going to have a heck of a time getting advantage to ornithoptor flight. And non-rigid industrial quality materials isn't exactly what our society is known for producing right now.

Re:birds (1)

njh (24312) | about 8 years ago | (#15688255)

It has also been said for many years that aeroplane wings work because a low pressure is created on the upper surface. What many people say does not always correspond to what scientists know.

I dunno... (4, Funny)

Anonymous Coward | about 8 years ago | (#15686926)

These things really didn't help Paul.

Re:I dunno... (0)

Anonymous Coward | about 8 years ago | (#15688219)

Yeah, but it enabled the whores to swoop by and cut down Taraza in half.

I had a few Ornithopters (1)

Orion Blastar (457579) | about 8 years ago | (#15686929)

in my MTG deck. 0/2 creatures with flying. I never knew they actually worked. I thought they were some crackpot invention that didn't really fly and was a MTG joke.

Re:I had a few Ornithopters (1)

Guiness17 (606444) | about 8 years ago | (#15686974)

Perhaps, but fire breathing Ornithopters were a great addition to any flying red deck, giving you cheap flying creatures, capable of delivering quite a punch...

Re:I had a few Ornithopters (1)

Transcendor (907201) | about 8 years ago | (#15687004)

Me too. But I didn't know they were good for anything else than having 3 free artifacts in the first turn, giving me the opportunity to bring a Frogmit (2/2, 4 Mana with affinity for artifacts) in before anyone else could play his creatures.. OMG... did I play like a mindless pile of mud those days...
(artifact lands are banned these days?! or just restricted? are ornithopters restricted too?)

Re:I had a few Ornithopters (1)

Archangel_Azazel (707030) | about 8 years ago | (#15687419)

*chuckles* I knew it was only a matter of time before M:tG was mentioned. Long live Baron Sengir :D

A.A

Re:I had a few Ornithopters (1)

Warg! The Orcs!! (957405) | about 8 years ago | (#15687998)

Artifact Land are restricted in all but Mirrodin block where they are banned. 'Cos they were just toooooo good.

Ornithopter + Enduring renewal + Life Chisel = Infinite Life
Ornithopter + Enduring renewal + Ashnod's Altar = Infinite Mana
Ornithopter + Enduring renewal + Fallen Angel = a creature with power/toughness = infinite/infinite

Ornithopters good!

paper airplane flapper (4, Informative)

avi33 (116048) | about 8 years ago | (#15686931)

My friend invented a flapping paper airplane [mac.com] 20+ years ago in junior high. Of course it's not nearly the same, since it reacts to pressure fluctuations instead of creating them. There are (pdf) instructions so anyone can be an ornithoptrix.

Wait... what?! (1)

GhaleonStrife (916215) | about 8 years ago | (#15686949)

Am I the only one that thought of Magic: The Gathering when they read the title?

Re:Wait... what?! (0)

Anonymous Coward | about 8 years ago | (#15687039)

Everyone seems to think about MTG when they read this... what about DUNE!

Re:Wait... what?! (0)

Anonymous Coward | about 8 years ago | (#15687073)

I searched for it... doesn't seem like such a good card. either way, I'll tap it with my icy manipulator and kill it with my royal assasin. your move.

Re:Wait... what?! (1)

Creedo (548980) | about 8 years ago | (#15687522)

Not a good card? A 0/2 with flying for free? That's a pretty good 1st round blocker. Throw blood lust on it to get a 2nd round 4/1 flying attack. Or toss an enchantment like "Armor of Faith", "Rancor", Holy or Unholy Strength or "Taste for Mayhem" on it for a 1st round bad assed flyer. Not bad at all.

Re:Wait... what?! (1)

joe 155 (937621) | about 8 years ago | (#15688191)

hmm... you could play it that way, in my deck I prefered to take the small damage in the opening turns in order to get set up with the more powerful cards later... I had a sliver deck and when you got the sliver queen along with 4 of the muscle slivers, a flying one and the one that gives them rampage you really get going... you could lose even 10 points, even 15, give it a couple of turns with that kind of power and it'd all be over... I miss playing MTG (and star-trek cards too...) why must I be seemingly the only nerd at my uni?

Re:Wait... what?! (-1, Troll)

east coast (590680) | about 8 years ago | (#15687113)

I'm sure there was a whole host of 12 year old homosexuals who thought the same exact thing you did.

Re:Wait... what?! (1)

pyrosim (856745) | about 8 years ago | (#15687464)

I certainly did.

Re:Wait... what?! (4, Insightful)

KylePflug (898555) | about 8 years ago | (#15687567)

Real nerds thought of Dune.

Hey editors, you got it right for once... (4, Interesting)

ColdWetDog (752185) | about 8 years ago | (#15686961)

A slashdot article that is

1) Interesting
2) NOT and infomercial or astroturf
3) Has a paragraph to page ratio of greater than 2
4) Has some modicum of detail
5) Not about SCO, Apple, Google or Mr. Bill

Congrats. Of course, the signal to noise ratio is still painfully small. But it's a start.

Re:Hey editors, you got it right for once... (2, Interesting)

QuantumFTL (197300) | about 8 years ago | (#15687051)

The easiest way to reduce SNR on things like slashdot, digg, etc is to apply a meta-filtering technique, perhaps through Yet Another Community Portal, but with much smarter filtering technology. A colleague and I have come up with an algorithm that would eliminate most of these problems, but after talking to Digg for a while about it, they weren't interested. If someone with a reasonable chance of success were to set up yet another community portal, I might be inclined to donate my research to its benefit.

Re:Hey editors, you got it right for once... (1)

WilliamSChips (793741) | about 8 years ago | (#15687138)

Why don't you just publish the formulae for all to see?

Re:Hey editors, you got it right for once... (1)

QuantumFTL (197300) | about 8 years ago | (#15687165)

Well there's nothing terribly "secret" about it (I suspect it is similar to how amazon reccomendations are calculated, but it may have a different mathematical basis), however I can't really publish it until I have real-life statistical data to test it on, as it assumes a very specific generative model that I can only conjecture represents the users of a site well. It is also possible that because the generative model does not translate very well to linear algebraic calculations (like, say, fixed size intermediate feature models), it will not be efficient enough to calculate on scales of hundreds of thousands of users (though I think it can be approximately optimized in polynomial time).

Either way, I really do need real life data to support this from something like Digg/Reddit (not slashdot) - where users are constantly rating things.

Re:Hey editors, you got it right for once... (1)

ColdWetDog (752185) | about 8 years ago | (#15687470)

as it assumes a very specific generative model that I can only conjecture represents the users of a site well. It is also possible that because the generative model does not translate very well to linear algebraic calculations (like, say, fixed size intermediate feature models)

Argle Bargle Morble Whoosh?

Oh you're wrong (2, Informative)

narftrek (549077) | about 8 years ago | (#15687341)

Sorry but if you had taken the time to RTFA instead of looking for a witty way to take a stab at the editors then you would have noticed that the article WAS about Mr. Bill. Mr. Bill was thier first remote controlled ornithopter. Maybe not the Mr. Bill you're referring to but Mr. Bill none the less. So you've violated your point #5 allowing ME to find that witty way to stab at the editors thusly proving they still are asshats. Thanks for the assist!!

Re:Hey editors, you got it right for once... (5, Funny)

RMB2 (936187) | about 8 years ago | (#15687372)

A slashdot article that is
.
.
5) Not about SCO, Apple, Google or Mr. Bill
Ironically enough, I'm not entirely sure you read TFA, because they clearly mention "a remote-controlled ornithopter, which they called Mr. Bill"

Huh, well 4 outta 5 ain't bad

Re:Hey editors, you got it right for once... (1)

OhNotSeven (869903) | about 8 years ago | (#15687705)

I hear ya.
Sory for going off-topic but I thought this is a good train of thought.

This is the kinda stuff that really matters..congrats, eds. Please keep looking for stories that

1. look into the future
2. not FUD or troll
3. interests the geeks of all flavors and distros
4. have a logical scientific progression of what is and what will be
5. may be come up with some kind of metric to improve the signal to noise ratio that parent alludes to. Tagging might help gauge what the readers think about a story. Here's one that can be a start (good or bad):

For every 10 stories selected, make the following selections: general scientific advancements (4), IT Tech (3), news and current affairs that do not have explicit political trolling (2) and let the last one be anything...whatever the whim seeks. For the whim can generate interesting ideas too.

Re:Hey editors, you got it right for once... (1)

Jodka (520060) | about 8 years ago | (#15687846)

Yes, but so unfortunate that someone spoiled a good moment by mentioning all those things in the discussion.

DeLaurier's Ornithopter (2, Informative)

Anonymous Coward | about 8 years ago | (#15686984)

My friend had been an engineer on the flapper project for years and it was only recently that the booster was added. As far as I understand, the wings do flex and have successfully propeled the plane on the runway to significant (~60kph) speeds without need for a boost, however, the plane kept oscillating into the ground. More than one interesting test day was the result. All I can say is "congratulations" to those on the flapper team...its been a long time coming. :) (I hope there will be an alumni party for those who have put so much effort into this project over the years.)

Flapping power from ... where? (4, Insightful)

Migraineman (632203) | about 8 years ago | (#15686985)

The professor's website is being hammered by us, so I've only got the Star article to go from. "The R/C turbine provides thrust to get up to takeoff speed, at which point the flapping wings take over." I didn't see mention of a secondary propulsion means that causes the wings to flap. Electric motor? Pedal power? Briggs & Stratton? I'm curious how much horsepower it takes to keep his bird aloft. Anyone know?

Re:Flapping power from ... where? (1, Informative)

Anonymous Coward | about 8 years ago | (#15688259)

It comes from an internal combustion engine.

Theres a fairly complex mechancial system that it drives to flap and twist the wings.

I went to a presentation by him a few weeks ago (I got the Institute), and had no idea they were this close to flying it!

Aloft for about 14 seconds... (1)

BadassJesus (939844) | about 8 years ago | (#15686999)

He did it just for the record. I mean, take a local news reporter and a camera man, construct something utterly impossible and be sure to name the thing properly, then ride it, make the news and you've gotten yourself a history record and maybe a Slashdot news entry too.

Re:Aloft for about 14 seconds... (1)

Deadstick (535032) | about 8 years ago | (#15687068)

Sure works for flying cars.

rj

Re:Aloft for about 14 seconds... (1)

RMB2 (936187) | about 8 years ago | (#15687386)

Yah, this guy clearly did it all for the fame. The Toronto Star, this guy has really hit the big time now.

Aloft for about 14 seconds...
Oh, and tell Orville and Wilibur to screw off... 12 seconds, ptttth. Clearly nothing will ever come of these "flying machines"

This machine is way cool but.. (2, Interesting)

Ougarou (976289) | about 8 years ago | (#15687020)

I doubt anybody would like to sponsor it. As everyone is working on getting things cleaner, this seems like a feul gusler.
Nobody should stop dreaming though, they should open a donation page and print names on the wings!

Re:This machine is way cool but.. (1)

RMB2 (936187) | about 8 years ago | (#15687403)

I'm not entirely sure you understand the difference between the concepts of "donation" and "print names on the wings". See, the latter is usually refered to as "sponsorship".

And the concept here is hardly fuel economy. Think about how many /. nerds read this article, and if that ornithopter was developed "in collaboration with XYZ Corp." that would be great for their image. I feel like there are a good few firms that might like to be a part of that.

If the wings had been (1)

zoomshorts (137587) | about 8 years ago | (#15687044)

Anything like a BIRDS wings, and not aerodynamic lifting bodies, I might have been impressed.

I cannot see how this would even qualify as a ORNIT-anything. Color me skeptical, but it could have
been just luck the contraption went anywhere at all. Flapping aerodynamic wings must have been fighting
the lifdthe wings naturally gave the craft.

Calling PURE , UNADULTERATED BULLSHIT over here. Blue ribbion winner!

Re:If the wings had been (0)

Anonymous Coward | about 8 years ago | (#15687091)

The wings -are- like bird's wings. They make heavy use of aeroelastic twist to provide appropriate thrust from the flapping motion. This guy was my aerodynamics professor in undergrad, and I have to say he's not only a technical genius, he also knows how to teach a mean class.

Anyway, from firsthand experience, these wings are more like bird wings than they are like airplane wings.

Re:If the wings had been (3, Informative)

Deadstick (535032) | about 8 years ago | (#15687109)

A bird's wing is an aerodynamic lifting body, and model ornithopters were flying before the Wright Brothers. They don't "fight against the lift" of the wing, but use it in a pretty sophisticated way.

We don't have human-carrying ornithopters because scaling effects get in the way. The ability of a wing to produce lift (and the muscle power available to it, in the case of a bird) goes up as the square of the size, but the weight goes up as the cube.

This is what limits the size of birds. A hummingbird can fly all day, even hovering motionless. A robin needs to rest once in a while. An eagle can only fly under muscle power in bursts; most of the time he has to soar on rising thermal currents like a sailplane. An ornithopter big enough to carry a human is going to need a LOT of power.

rj

Re:If the wings had been (1)

Mydron (456525) | about 8 years ago | (#15687188)

What you say regarding bird size correlating to flapping endurance seems to make sense. However if you consider migratory birds your thesis starts to fall apart. There are many long-distance migratory birds that can fly all day and many of them are large, heavy birds such as geese, swans, and storks.

Re:If the wings had been (3, Insightful)

samurphy21 (193736) | about 8 years ago | (#15687276)

I suspect that this can be chalked up to the proportionatly enormous wing muscles these birds have, which is why ducks and geese are sought after game birds. They have tons of white meat compared to, say, a crow. They also have a relatively long wingspan for their weight, I think.

Also, migratory birds don't fly the whole way from Canada down south in one go. They often stop to rest and refuel (and crap on my car).

I'm no ornithologist, but these seem like logical deductions. Could be wrong.

Re:If the wings had been (2, Informative)

Afrosheen (42464) | about 8 years ago | (#15687344)

All logical conclusions. When anything migrates, it has to stop and refuel and rest eventually. Also, it's not like there's one bird flying his ass off for 3000 miles all by himself. Ever notice the reverse V formation geese use when migrating? It's the most efficient formation for distance flying. The lead bird does most of the work, and each bird in sequence behind the lead does less and less work to stay aloft, because they're in a drafting chain. The birds at or near the back of the V are working the least while the lead works the most. They often rotate the lead bird out from one of the rear birds.

  Another advantage ducks and geese have is that they are able to build up great fat reserves which is converted into energy for long endurance flight. Simply compare the meat of a chicken to the meat of a duck and it becomes obvious which one has more fat content. Ducks and geese also need these fat reserves to survive colder climates for short periods of time as well (pre-migration).

  You're correct on your point of wingspan/size ratio of ducks/geese/swans. It seems the longer a bird must fly the greater the wingspan is needed. See the albatross for the best example of this. They have a wingspan of up to 11' 11" (no that's not a typo, 11 feet 11 inches total wingspan).

Re:If the wings had been (2, Interesting)

TubeSteak (669689) | about 8 years ago | (#15687727)

They have tons of white meat compared to, say, a crow.
http://www.straightdope.com/classics/a981204b.html [straightdope.com]

Basically, white meat stays white because farmers clip their chickens' wings to keep them from exercising those muscles much.

The more a muscles is exercised, the darker the meat gets.

Re:If the wings had been (1)

samurphy21 (193736) | about 8 years ago | (#15688240)

Yes, you're right, I was thinking chickens, not ducks. What I meant was that they have large amounts of breast muscle, which WOULD be white meat, if they were crippled, farm grown birds instead of wild, migratory ones. Sorry.

Re:If the wings had been (1)

pauljlucas (529435) | about 8 years ago | (#15687373)

We don't have human-carrying ornithopters because scaling effects get in the way. The ability of a wing to produce lift (and the muscle power available to it, in the case of a bird) goes up as the square of the size, but the weight goes up as the cube. This is what limits the size of birds
So what about these [wikipedia.org] ? They flew and were big. Really big. So why can't birds get that big?

Re:If the wings had been (1)

Deadstick (535032) | about 8 years ago | (#15687565)

Very lush, swampy environment with lots of food...they didn't have to fly very far and expend much energy to find it.

rj

Re:If the wings had been (1)

theshibboleth (968645) | about 8 years ago | (#15687575)

Well, yes, but pterosaurs aren't brids; they would presumably have their own rules.

Re:If the wings had been (1)

pauljlucas (529435) | about 8 years ago | (#15687774)

The fact that they aren't birds is irrelevant. The same laws of physics and chemistry appy to all lifeforms. The real question is why lifeforms can only get so big.

Re:If the wings had been (1)

zoomshorts (137587) | about 8 years ago | (#15687913)

These things have been ASSUMED to fly, but no one has ever seen them fly.
They are not aerodynamic.

Fossils that have things that look like wings, do not mean the things actually flew.
They are more like flightless Bats.

If you look at the "ornithopter", you will see wings that have aerodynamic cross sections.
UNLIKE bird's wings, who have a small frontal portion of the limb partially like aaeroplane wing.

A true "ornithopter" would mimic a birds wing FAITHFULLY. Flight has never been accomplished
using that design. Gliding either. Parasails and hang gliders use a different method, and glide, not fly. Sure. if a wind carrying more power than the weight of the object blows in an upward direction on the object, you get simulated "flight". I'd bet you would argue that tornadoes allow flight also. Wikipedia be damned. Disinformation is just that.

Re:If the wings had been (1)

thsths (31372) | about 8 years ago | (#15687781)

> Calling [...] BULLSHIT

I tend to agree. The point of an Ornithopter would be to provide both lift and thrust with one element: the flapping wing. But this contraption uses a mini turbine to provide thrust, and it flaps the wing only for ... no purpose at all? Or rather it flaps the wing for being classified as a flapping wing contraption.

Even for real a Ornithopter I remain skeptical. Using wings for lift and turbines for thrust is a very solid principle with a minimum of moving parts. To be precise, there is one (!) moving part: the turbine shaft with fan and turbo blades. Compare that to maybe 100 moving parts in a car engine, or even a flapping wing mechanic, you can easily spot the advantage of the classical yet powered aircraft.

The Spice Must Flow (2, Funny)

ThreeE (786934) | about 8 years ago | (#15687086)

sniff... sniff...

Orhithoserver ? (2, Funny)

alexhs (877055) | about 8 years ago | (#15687125)

It flew for 14 seconds [...] However it landed with a bit of a crash

Is that their server being slashhunted that they're talking about ?

Was the crash as quick as the server's? (1)

cardoso (90714) | about 8 years ago | (#15687163)

Only a few comments, a nice sunday afternoon with no people at home and the site is already gone? I fear Slashdot. I really do.

Old News (0)

Anonymous Coward | about 8 years ago | (#15687304)

this is old news, ornithopters have been around for years.
Since magic the gathering 5th edition as i recall.
Now THAT is news for nerds.

Re:Old News (1)

night_flyer (453866) | about 8 years ago | (#15687376)

What kind of nerd are you? They were introduced in the Antiquities set!

Don't be fooled... (1)

Manchot (847225) | about 8 years ago | (#15687328)

I know this may initially seem like a silly thing for people to build, but don't be fooled. Just as helicopters and airplanes have both found their niche, it is possible that ornithopters could one day fill another one. The fact that such a large one can fly even for a short amount of time is truly remarkable.

Small scale electric rc ornithopters work well (1)

caseih (160668) | about 8 years ago | (#15687396)

There are already small-scale (miniature compared to this) radio-controlled ornithopters that seem to fly every bit as well as a normal electric parkflyer. The problem is scaling the idea up. What makes this version somewhat revolutionary is that fact that it is full scale. The forces that the various parts of an ornithopter would experience when the flapping motion is occurring are pretty great, yet the materials have to be light-weight. Sounds like this flight was a complete success, despite the crash at the end. A sheer wind can cause problems for even the largest conventional airplane. This plane is also interesting in that it is human-powered, with assistance from a 60-lb thrust jet turbine. Whether or not an ornithopter is anything more than a curiosity remains to be seen. I doubt we'll be seeing jetliner-scale onithopters ever. The efficiency of the conventional design is so great at large scales that I doubt it will ever be beaten by a flapper. On the other hand, perhaps advances in materials will someday allow flying human-powered flappers to become a sport like bicycling.

Re:Small scale electric rc ornithopters work well (0)

Anonymous Coward | about 8 years ago | (#15687577)

This is not a human powered craft... here is a quote from this site http://www.gizmag.com/go/3533/ [gizmag.com] :


How It Works

The full-scale ornithopter is an engine powered aircraft that carries one pilot. All of the thrust and nearly all of the lift is created by the mechanical flapping of the ornithopter's wings. The two wings of the craft are joined by a centre section which is moved up and down by pylons connected to the drivetrain. The wings' thrust is due primarily to a low-pressure region around the leading edge, which integrates to provide a force known as "leading-edge suction". The wings also passively twist in response to the flapping. This is due to a structure that is torsionally compliant in just the right amount to allow efficient thrusting ("aeroelastic tailoring"). It should be noted, though, that twisting is required only to prevent flow separation on sections along the wing. It does not produce thrust in the same way as required by sharp-edged wings with little leading-edge suction.


This was clearly before they added the extra booster for initial thrust.

I had to do it... (0)

Mister Whirly (964219) | about 8 years ago | (#15687440)

"There's snakes on the motherf*cking ornithopter!"

Manned Ornithopter Flight Already Done (4, Interesting)

c41rn (880778) | about 8 years ago | (#15687548)

According to this article [ornithopter.org] , manned ornithopter flight had been achieved in 1942 by Adalbert Schmid. Like the ornithopter in the article, it was a manned, engine-powered ornithopter that could take off under its own power. The difference, it seems, is that Schmid's orni' had fixed wings in addition to the flappers whereas the one that flew today had only the flapping wings. Not to discredit or lessen their excellent achievement today, just think the history is interesting.

Incidentally, you can buy some pretty neat ornithopter kits from www.ornithopter.org [ornithopter.org] . I'm not affiliated or anything, just interested in flapping-wing flight and experimenting on a small scale.

The development of flapping wing flight is interesting because it can also have other applications. I am especially interested in the use of 'flapper' designs in water craft (specifically for use in robotics). An interesting use of similar tech can be seen in these kayaks [hobiecat.com] . Intersting stuff.

mod dowN (-1, Troll)

Anonymous Coward | about 8 years ago | (#15687779)

nOpenBSD, as the [goat.cx]
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