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Watch a bird take off. Start with some pigeons, then some sea gulls. If you can, watch an albatross - on YouTube if nothing else. As you get larger, you get heavier; as you get heavier you need more lifting force (ie, bigger wings, moving faster). Recall that weight is a function of volume and increases with the cube of your dimensions, while lifting force is a function of surface area and only increases with the square of your dimensions. Very very roughly if you're twice as big, you get four times the surface area but eight times the weight, meaning that as you get larger flying goes from being "difficult" to impossible. And a man is large, and the batteries and motors he was allegedly using just add weight.

All of which is a long way of saying that he runs very slowly, his wings are very small, and they flap very slowly. The first couple seconds of him after take off our patently absurd; you need to be applying - somehow - hundreds of pounds of force to the air to push you off the ground. Yes, fine, he has a wonderful wing design and some amazing motors and (apparently) zero weight batteries. Fantastic! But none of the components in that video are producing hundreds of pounds of force. (A commenter at Wired estimates that the servo motors are theoretically applying enough force to pick up a two ton load, in fraction of a second. If we had this tech, we could fly, although that wing design probably couldn't. We could also make Iron Man-style powered armour. Unfortunately, we don't have this tech.) The whole thing is multiple orders of magnitude off from the realm of "remotely possible".

There are just so many red flags. The bizarre edits, the poor filming, the ridiculous design of the wing, the secrecy, the way nobody in the video acts right, the way the wing magically changes designs in different shots, the fact that the wing is clearly not fully loaded, the weird clothing and gear choices, etc., etc., etc. Wired has been hoaxed hard.

For the record, he's budgeting around 17 m^2 surface area for wing and 100 kg for pilot (http://www.humanbirdwings.net/about/working-on-the-wings/). That's about 5 kg/m^2 wing loading, well within range of something for a microlight(http://www.caa.co.uk/default.aspx?catid=1416&pagetype=90...) if a bit heavy for an unpowered glider.

EDIT: The wing surface (that kite he mentions sacrificing) is from one of these ( http://ride.slingshotsports.com/2012-Fuel# ) which is intended for exactly this sort of thing--supporting a human in flight.

Note that in the design blog the motors are being run through a 25:1 planetary gear. The family of motors in question can put out in excess of 2kw ( http://www.hobbyking.com/hobbyking/store/__17986__Turnigy_Ro... or http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProdu... ). So, no, the power plant is quite capable.

It's not the power output of the motors I was questioning, but the overall strength of the system. A back of the envelope calculation (from a commentator at Wired) suggests we're seeing a lever ratio of around 30:1; simplifying greatly that implies each side is moving a 1.5 ton weight back and forth multiple times per second. This is challenging for far more than the motor.

Mind you, 2000w does sound low. The Festo SmartBird weighs less than 500g, and uses around 25w to fly. If you scale it up linearly, that says 2000w would be enough for 40kg, which is less than half what we need. But the Festo SmartBird is a vastly more sophisticated design, and among other things actually flaps its wings in a way which generates lift, unlike this guys design. (Very useful, that.) It's going to be much more efficient than this wing design, so we're actually looking at a much larger power deficit.

Incidentally, the Festo SmartBird is a pretty amazing project; anyone who found this wing design interesting would probably be interested in it. Check out this writeup with a brief video of the bird in flight[1] or this much longer video of the design process[2].

The second link, in particular, underscores just how impossible the idea of some guy on his own throwing together some wings and managing to fly is. Bird flight is an amazingly hard problem to solve, even for a bird sized model.

[1]: http://www.robaid.com/bionics/festo-smartbird-mechanical-bir...

[2]: http://www.youtube.com/watch?v=kA7PNQiHT1Q

Finally someone pulled out meaningful fact about flying. How funny people keep saying about video without taking into account any engineering or physical requirements to make this real.

Annoying as hell, isn't it?


More usefully, I don't mind if this turns out to be a fake--but this off-the-cuff "no it is not possible ever" is so narrowminded when not combined with credible facts and analysis.

I agree. It is good to be skeptical - as they say extraordinary claims require extraordinary evidence. Experts are trained to be skeptical. I am not saying that video may not be a fake but I am also equally skeptical about all the expert opinion on the impossibility of it all. And that is because experts have a long tradition of often being dead wrong about what is possible. Lord Kelvin - who was England's top scientist and President of the Royal Society flatly stated in 1895 that "Heavier-than-air flying machines are impossible" - just a decade before he was proven wrong. There are many more similar examples in the history of progress. It is a good thing inventors also have a long tradition - of ignoring experts and just trying to achieve what has been claimed as impossible.

That approximate wing loading calculation is assuming there is sufficient force to fully load the wing. He's not going to get that load on the wing by jogging a few feet and flapping those things at 1hz.

Birds don't fly by flapping up and down - they flap down and back, then fold the wing and pull it forward and up.

If you just flap and up and down you move up and down, but you don't fly. You need motion to cause forward acceleration, not just up and down bobbing.

Fake, it's simply impossible for the shown flapping method to cause him to fly.

See here: http://www.youtube.com/watch?v=PSikfcJezy4#t=180s and notice how the bird folds the wings as it pulls them up, then spreads them as it pushes down. The folded wings give less resistance to the air than the spread ones, and that difference lets it fly. Without that you can't fly by flapping. To move forward it also has a front back motion that is harder to see in the video, but is still visible.

As someone has pointed out elsewhere, you can see in one of their other videos that they have major inconsistencies in the videos that they post. For instance, in this picture, http://i.imgur.com/3Fgct.jpg you can see that there is no black square above the "S" logo. Then, the camera points downward, then upward again, and there is a black square above the "S" logo.

This video is very fake.

That's the most annoying inconsistency for me. I think that could be a patch to the wing applied after they managed to pull out the cloth from the spar (if you look at the blog a bit, there are some posts showing that issue). I think the shitty cut around 1:20ish could be them looking down during a screwed launch attempt, and splicing back in after adding the patch. You'll notice in the following video the patch is there from the start.

There is a Dutch news clipping from about a week after video 13 that shows the dude without the patch, which is puzzling. Again, easily explained as using an old photo from before 13, but still.

I also expected to see more up-down, up-down movement from the on-board video (with respect to ground) to coincide with the power strokes.

I think we are all focusing on the wrong issue - that is whether this is real or fake. Who cares! What matters here is that this guy has come up with the idea of using robotic extensions of our limbs, powered by electric motors, to help us in achieving flight.

If we now switch to this mindset, the engineering and tools that we have today should allow us to achieve the desired goal.

So thanks for the hoax, Flying Dutchman - you have started something new here, and your name will not be remembered by what you did, but rather by what you did not and how others used your idea to achieve it.

Oh look he even has a animated model of this thing in Maya ;) He conveniently shows it of while "explaing" his wings. Here @20sec : http://www.youtube.com/watch?feature=player_embedded&v=T...!

As a followup, note that the creator of the hoax has admitted it[1]. What a surprise!

[1]: http://news.ycombinator.com/item?id=3740972

Franky My Dear, I don't care how the video was shot or how the wings were designed. I just know now, that it is Efiing Possible!!!!

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