Dutchman flies by flapping his arms

[walker 0]

Hi all

In reply to PELHAM

add the Register and TIME to your list

http://www.theregister.co.uk/2012/03/21/flying_man/

http://techland.time.com/2012/03/21/man-flaps-android-powered-bird-wings-flies-with-wii-remote/

As I keep pointing out if it is a fake it is damn good one and as I said Cudos and an Oscar for the quality.

So Fake or real a wonderful video either way.

Kind Regards walker

[PELHAM 10]

sigh....I believe I can fly.....

[MrBump 10]

Rhett Allain, Associate Professor of Physics at Southeastern Louisiana University, analyses the video badly, ignores the physics completely, just awful.

http://www.wired.com/wiredscience/2012/03/analysis-of-the-human-birdwings/

In what way does he ignore the physics completely?

[rksl-rock 1301]

Ok so i've just got back from my regular lunch with 3 friends at Lostock and we ended up discussing this. The universal consensus was FAKE!

I think understandably these guys dont want to be connected with this in anyway but they are all professional Aerospace engineers with collectively 61 years of experience working in the British defence industry.

Richard - ~24 years of control systems design. For the layman. This is a guy who designs the controls for flying aircraft and currently missiles. Specifically actuators that move the flying surfaces on planes and missile.

Tony - ~17 years of Stress Analysis. Again in simpler terms he works out the stress acting on missile bodies ensuring that they can hold together in flight.

Doug - ~20 years Design Engineer. Currently he's working on the next generation of missile bodies. Specifically near hypersonic intakes. Basically he's as close to an aerodynamicist as I know.

Add my own 18 years experience It took us about 2 mins to raise so many questions that there is no doubt at all in anyone's mind that its fake. I think the best quote of today was "Now thats what happens when you leave a film student and a cheeky engineering student alone for too long".

Collectively, we have no doubt he built the wing and that they flap. We also have no doubt that he did run down the field wearing a "flapping wing backpack" but we can not believe that he flew as shown.

More obvious areas of ... well lets just say "concern":

• Mechanical strength of the machine given what is shown in pictures and video. Even if the wings were static its construction is far to weak to support the forces imposed on a flapping wing in flight. Look at a hang glider, similar wing span and they require significant bracing to prevent the wings just simply folding up.
  
• Even given the torque rating of the motors it wouldn't be enough to move that long a wing with that much surface are once aerodynamically loaded at speed.
  
• The fabric on the wing is not being properly loaded as it should if it were flying as we led to believe.
  
• Rate of climb seems far too high given the available power and shape of the wing.
  
• Angle of attack of the wing in the steady "glide" is unlikely given the speed.
  
• CofG/Body position at various times in the footage.
  
• The disparity in the altitude from the 1st and 3rd person point of view.
  
• The footage itself as he "lands" look carefully at the "inflight" camera and the 3rd person shot. Estimate the position relative to the footpath and ask yourself if it looks right.
  

We've had a lot of fun debating this. Doug is at this very minute trying to work out what it would take to do it for real. But none of us believe he flew.

We just wish he had. :p

Edited March 21, 2012 by RKSL-Rock

[PELHAM 10]

In what way does he ignore the physics completely?

Read this entire thread, he misses the most obvious thing which I spotted after just 1 viewing. Dead3yes explains it best (he says even a child can understand it and he is correct). There is much to understanding the forces in a flapping wing. Waffling about the power required or mass versus wingspan misses the entire question completely. It's not the engine that matters here, it's the wing itself. A flapping wing works because of the way it moves. That is why they are so immensely complex and why engineers have struggled to understand and replicate the basics.

That is why you get nowhere strapping an aerofoil to each arm and flapping. Even if you had the strength and low mass required you would never get off the ground because you could never move the wing in the correct way. I am profoundly disappointed in many of the learned people that don't get it. If I was Rhett Allain's Dean, I would probably throw him out of my office window for this.

Someone laughed at a cartoon video showing a parrot flying that I posted, but that is all you need to understand it. Look at the up and down stroke of the wing, look how each feather changes and how the wing shape folds and opens. There are 1000's of changes in each cycle of movement.

Edited March 21, 2012 by PELHAM

[Tonci87 163]

I'm mostly in the Fake camp too. I *WANT* this to be true but the engineer in me is just laughing its ass off shaking its head and saying good try.

My exact feelings.

This is fake on so many levels that I´m really surprised that anybody took this seriously. I guess people wanted it to be true.

And this:

Read this entire thread, he misses the most obvious thing which I spotted after just 1 viewing. Dead3yes explains it best. There is much to understanding the forces in a flapping wing. Waffling about the power required or mass versus wingspan misses the entire question completely. It's not the engine that matters here, it's the wing itself. A flapping wing works because of the way it moves. That is why they are so immensely complex and why engineers have struggled to understand and replicate the basics.

That is why you get nowhere strapping an aerofoil to each arm and flapping. Even if you had the strength and low mass required you would never get off the ground because you could never move the wing in the correct way. I am profoundly disappointed in many of the learned people that don't get it. If I was Rhett Allain's Dean, I would probably throw him out of my office window for this.

Someone laughed at a cartoon video showing a parrot flying that I posted, but that is all you need to understand it. Look at the up and down stroke of the wing, look how each feather changes and how the wing shape folds and opens. There are 1000's of changes in each cycle of movement.

[MrBump 10]

Read this entire thread, he misses the most obvious thing which I spotted after just 1 viewing. Dead3yes explains it best.

The Dead3yes example of a inflexible paddle in water isn't really relevant here as the wing is itself clearly flexible and is at least capable of changing it's angle of attack.

That is why you get nowhere strapping an aerofoil to each arm and flapping. Even if you had the strength and low mass required you would never get off the ground because you could never move the wing in the correct way. I am profoundly disappointed in many of the learned people that don't get it. If I was Rhett Allain's Dean, I would probably throw him out of my office window for this.

Hmmm, ornithopters have flown using wings designed for passive aeroelastic wing deformation to achieve lift and thrust from a mechanical wing that simply moves up and down... sorry but I'm not buying your idea that's there's necessarily an issue of cancellation of lift that other people seemed to have missed. Maybe the reason many of the learned people don't get it is because you're actually wrong?

Someone laughed at a cartoon video showing a parrot flying that I posted, but that is all you need to understand it. Look at the up and down stroke of the wing, look how each feather changes and how the wing shape folds and opens. There are 1000's of changes in each cycle of movement.

Except these wings don't work exactly like a bird's wing as Dr. DeLaurier explains:

"In an ornithopter the wings must produce both the lift to counteract the weight of the aircraft, and the thrust to counteract the body drag. Lift is produced in the conventional way, with the oncoming air striking the wing at a positive angle of attack; thus no feathers, valves or folding of the wing is required to produce lift. The key is to produce enough thrust with the wing to keep the aircraft flying at the required forward velocity. This thrust is produced by placing the wing at a lower angle of attack, relative to the local flow velocity, on the upstroke, and at a higher angle of attack on the downstroke. It can be seen in the figure below that this results in a large amount of lift and thrust on the downstroke and a small amount of lift and drag on the upstroke. The net result is positive lift and positive thrust."

http://hpo.ornithopter.net/?q=content/technical-info

Personally I also think this is fake, too much drag from those wings and the man's shape, doesn't seem right, but it's more feasible than I think you understand.

[ProfTournesol 956]

Last time i saw a "Dutchman flies by flapping his arms" was in a coffee shop.

[Dead3yez 0]

The Dead3yes example of a inflexible paddle in water isn't really relevant here as the wing is itself clearly flexible and is at least capable of changing it's angle of attack.

LOL Barely.

[PELHAM 10]

The Dead3yes example of a inflexible paddle in water isn't really relevant here as the wing is itself clearly flexible and is at least capable of changing it's angle of attack.

Hmmm, ornithopters have flown using wings designed for passive aeroelastic wing deformation to achieve lift and thrust from a mechanical wing that simply moves up and down... sorry but I'm not buying your idea that's there's necessarily an issue of cancellation of lift that other people seemed to have missed. Maybe the reason many of the learned people don't get it is because you're actually wrong?

Except these wings don't work exactly like a bird's wing as Dr. DeLaurier explains:

"In an ornithopter the wings must produce both the lift to counteract the weight of the aircraft, and the thrust to counteract the body drag. Lift is produced in the conventional way, with the oncoming air striking the wing at a positive angle of attack; thus no feathers, valves or folding of the wing is required to produce lift. The key is to produce enough thrust with the wing to keep the aircraft flying at the required forward velocity. This thrust is produced by placing the wing at a lower angle of attack, relative to the local flow velocity, on the upstroke, and at a higher angle of attack on the downstroke. It can be seen in the figure below that this results in a large amount of lift and thrust on the downstroke and a small amount of lift and drag on the upstroke. The net result is positive lift and positive thrust."

Personally I also think this is fake, too much drag from those wings and the man's shape, doesn't seem right, but it's more feasible than I think you understand.

I am fully aware of ornithopters because I have this video saved on my hard drive - this is a real attempt that fascinated me at the time:

That is exactly what I was talking about, you have to move the aerofoil in a precise way. Also Dead3yes example is perfectly correct because if an aerofoil is kept at the same angle while moving up and down it will produce no net lift or thrust. That is clearly what happens in the fake vid, the angle of attack doesn't change. With a wing of that chord you would be able to see it clearly. A better natural example of an ornithopter wing is a high speed insect wing. The wing twists to reduce air resistance on the upstoke as the ornithopter wing does, the insect just does it far more efficiently. My point still stands, any flapping wing has to twist or fold on the up stroke or you get 0 lift.

I said it on page 2.

So nooooo I'm not wrong unless Dr. Delaurier is too.

Edited March 21, 2012 by PELHAM

[sprayer_faust 0]

Hehe. An interesting debate. :) RKSL-Rock has written some excellent arguments.

You can also make a quick estimate for average power of the wing-man just by looking at the potential difference over time.

From 00:32 to 00:48 (in 16 s) he ascended about 20 m. That is (80 kg * 9,8 m/s^2 * 20 m)/(16 s) = 980 W of pure mechanical power.

So about 980 W (with his arms) during every one of the 16 s. Pretty impressive. :D

[Smurf 12]

A better natural example of an ornithopter wing is a high speed insect wing. The wing twists to reduce air resistance on the upstoke as the ornithopter wing does, the insect just does it far more efficiently. My point still stands, any flapping wing has to twist or fold on the up stroke or you get 0 lift.

This?

[Flash Thunder 10]

Its official man because of the GO PRO.

[PELHAM 10]

This?

Yes that, perfect illustration of the angle of attack change. If he flapped it up and down without that twist - nada, he would not get off the ground.

[Smurf 12]

Also guys, remember this? Pure BS.

[Beagle 684]

Old news, Jesus did that nearly 2000 Year ago. But it's nice to see that ancient sports get revived just like flying with flapping wings..as we all know it worked great 3800 years ago. You just have to stay away from the sun. Btw I believe the Plaping technology can work by just angle of attack change by a fleaxible wing covering. I had a mechanical bird when I was young the flew of its own by flapping that way, driven by a twisted rubber band.

A bit lieke this but less advanced.

Key word is Ornithopter, works very good on small scale.

Edited March 22, 2012 by Beagle

[Sekra 10]

Makers of the vid confess its a fake down to them using fake names: http://www.popsci.com/technology/article/2012-03/self-powered-flying-dutchman-fake-right-down-his-name

[soul_assassin 1750]

oh well. Shame. My will to believe was strong with this one.

[rksl-rock 1301]

LMAO Even the BBC are reporting it as real. (You'll have to go past the Pirate Bay "April fools special" UAV Load balancing servers LMFAO...)

http://news.bbc.co.uk/1/hi/programmes/click_online/9708309.stm

"Smeets" must be laughing his ass off.

[dm 9]

And the website of the media company that faked it: http://revolver.nl/index.php?page=newsdetail&CID=2144

lolol, fakengay

[Tonci87 163]

OK now that we have the confirmation we can laugh at all the people who believed it was real, wich seems to be 90% of the people who watched it. Is mankind really that stupid?

[PELHAM 10]

LMAO Even the BBC are reporting it as real. (You'll have to go past the Pirate Bay "April fools special" UAV Load balancing servers LMFAO...)

http://news.bbc.co.uk/1/hi/programmes/click_online/9708309.stm

"Smeets" must be laughing his ass off.

Ohhh that's just made my day! My long held suspicion that the BBC Click team start each day by looking at wired.com is basically proven! Someday soon I'm just going to stop paying the licence fee like many others.

---------- Post added at 02:40 PM ---------- Previous post was at 02:14 PM ----------

OK now that we have the confirmation we can laugh at all the people who believed it was real, wich seems to be 90% of the people who watched it. Is mankind really that stupid?

Yes, be afraid of Zombies, they really do exist, the brain dead are all around us...............

[Dwarden 1125]

lets skip the fact about OP being fake and let's talk just about what's possible with correct approach :)

6s

it's doable with proper approach ... i seen already RC models of birds flight / ornithopter and also dragonfly

these are quite old videos there are many newer, including e.g. RC models flying like hummingbird and so on ...

[rksl-rock 1301]

lets skip the fact about OP being fake and let's talk just about what's possible with correct approach

it's doable with proper approach ... i seen already RC models of birds flight / ornithopter and also dragonfly

...

these are quite old videos there are many newer, including e.g. RC models flying like hummingbird and so on ...

As an aerospace engineer with some practical experience of lightweight materials I'm going to say making a set of wings like this is not practical with our level of tech at this time.

We have human powered flight already using the most efficient methods and design available. The machines we produced are amazing. They are truly works of art in themselves. You also need to look at the size of these machines, look at the wing area required to lift a human, wearing spandex shorts and nothing else into the air.

Now look at an ornithoper. Its complicated, inefficent if you have an inorganic power source and very hard to control. I can't see a way to do it with the currently available materials. They are just too heavy for an unassisted human.

Power Issues

So staying with the fact that we're talking about "assisted" human flight. I can't think of a lightweight power supply that provides the sustained output that is needed. Either in the civil or military arena. I haven't done any calcs on the draw required but for any length of sustained flight you are talking about a serious output. Even the latest LiPo cells aren't capable of that sort of capacity.

Mechanics of Scale

Yes you can make little RC ornithopters but it isn't just a matter of scaling up the "Dragonfly" that you bought in the toy store. If you tried you'd rapidly find that the power required to move the mass in the wings is simply more than any current portable power supply can achieve. And the torque required to move those wings would mean some serious actuators or motors, adding more mass. Which requires more power to overcome. Which means a larger power cell creating more mass. So we need better actuators that require more power and so on and so on. At some point it just becomes easier to change the design.

Evolving Nature vs Efficient Design

This is the reason that "we" use the far more efficient design of fixed solid wings and jet engines. Avgas/JP4 is the best source on energy/kg we have right now. And it has the added bonus that as you use it, it burns away making the aircraft lighter over time and therefore more efficient. Where as in nature and in particular birds, well they don't have the luxury of jet engines and avgas. It's why most birds are relatively small, lightweight and fragile. Once you reach this "limit of scale", You are in the realm of soarers like the Albatross and Giant vultures. Even the largest of them are much less than half the mass of the average man.

I honestly think we've already seen the best man can achieve. The hang-gliders running off cliffs and hoping that the laws of aerodynamics haven't been changed while they weren't looking.

But it's always nice to dream. And maybe one day some one will make those ultra light materials and the ultra efficient power cell and motors to make this a reality.

EDIT - Lets not forget control issues too. The larger the wing the more critical the control dynamic becomes. Especially in tailless planforms like a bird since they are inherently unstable.

Edited March 23, 2012 by RKSL-Rock

[Tonci87 163]

Well RKSL rock summed it up already, ornithopters are cool but they are just to inefficient. If ducks could grow jet engines out of their ass, then they wouldn´t need to move their wings at all. BRB, I´m going to find myself a duck and feed it with chilli and bean soup....