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Human Flight

  1. Nov 25, 2006 #1
    Stupid question: can people fly? Evidently, one doesn't see people flying around the streets, but is it possible? Has anyone done studies on whether this is possible or not? Any articles on this would be highly appreciated. Has anyone actually done this?

    Furthermore, how does physics apply to this? My rudimentary knowledge estimates roughly 800 N is needed for a 70 kg person to fly. Supposing one wanted to fly for 1 km, then this would be 800 000 J or 191 kC. And if one wanted to cover that 1 km in say 3 min, that'd be 64 kC/min, which is 3800 kC/hr, which is a hell of a lot. I believe that fast running takes about 1000 kC/hr. Then again, it'd still be a miracle if one could just fly 100 m. Please correct my physics if I'm wrong. In any case, how viable is this sort of calorie output for small amounts of time (e.g. 30 secs, a few minutes).

    I would appreciate extremely any articles on studies done regarding this, and also if it's viable at all.


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  3. Nov 25, 2006 #2


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  4. Nov 25, 2006 #3
    Thanks, russ_watters.

    Mmmm....that's really cool. So it has been done before, though he was sort of cheating with that bicycle stuff. Has anyone flown just with arms and legs plus wings (no bicycles, metal rods, gears, etc.) i.e. like Daedalus and Icarus of legend? Any further articles regarding the topic would also be highly appreciated.
  5. Nov 25, 2006 #4


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    Why don't you try it and let us know how it turns out? :rofl: I'm sorry, I couldn't resist. I remember reading the thing about pedaling across the Channel years ago. I'm not aware of anyone who has flown by strapping wings on. Just hang gliders.
  6. Nov 25, 2006 #5
    Actually...maybe I will try it...whether it succeeds or not is another story. This is one of the things I'm thinking of doing for my research project this year.

    Can someone give a physics analysis of this? i.e. how much energy and power it would take to maintain flight.
  7. Nov 26, 2006 #6
    Research project for which class?
  8. Nov 26, 2006 #7
    you need more than physics, you also would need to know a little something about biology. If you are referring to a human using his arms to flap a pair of wings, forget about it. The physics part would require a lift greater than 700 N for a human to reach flight. However, biologically, no human on earth could flap that hard or fast. I saw somewhere that if birds were of compariable size to humans, they could outrun a ferrari and benchpress thousands of pounds.

    Using human powered mechanisms is possible (duh). That is where aero engineering is born. If humans were somehow able to fly by themselves, why would the Wright brothers have even bothered?

    http://PropulsionAccess.com [Broken]
    Last edited by a moderator: May 2, 2017
  9. Nov 26, 2006 #8
    Research project for science/engineering fair.

    Thanks for the info, carp. Which article did you get those bird facts from? Also, how much power exactly can the human body output via arms, legs, etc.?

    As for the Wright brothers, flapping arms takes a lot more energy than sitting in a plane ;)
  10. Nov 26, 2006 #9


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    The reason for "that bicycle thing" is that our human legs are much stronger than our arms. and when the dinosaur ancestor of the birds started to evolve wings, they couldn't use them to fly either, but they could run very fast and use the proto-wings as stabilizers. So learning a little biology wouldn't hurt you.

    You might also see if you can find an online video of the famous newsreel compilation of failed human flight experiments in the early twentieth century.
  11. Nov 26, 2006 #10
    selfAdjoint, that's rather evident that legs are stronger than arms in humans; more common sense than biology (I never actually learned that in biology). My point wasn't to not use legs; it was to not use bicycles. It's, well, much more idealistic to fly without using bicycles, i.e. by flapping your arms/legs.

    Mmmmm....it seems somewhat decided that one cannot fly using human power without bicycles...if anyone has anything to the contrary, I'd be really interested. Thanks for all the replies.

  12. Nov 26, 2006 #11


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    No, it isn't possible for a human to propel him/herself efficiently enough by flapping wings.
  13. Nov 26, 2006 #12


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    Yes. History is dotted with many ambitious entrepreneurs who have successfully flown for short distances of a few dozen to a few hundred yards.

    Unfortunately, while none of the methods has succeeded in the Holy Grail of human flight: horizontal flight, all of them have succeeded extremely well with the rather easier component of vertical flight.

    A mystery remains why history does not recount any subsequent attempts of any of these fliers.

  14. Nov 26, 2006 #13
    I think you should look into a different topic. Maybe something like measuring the drag on bodies.

    Your premise for this project is fundamentally wrong and will result in a F.
  15. Nov 30, 2006 #14
    without gene splicing, anabolic steroids, cybernetic implants, or rocket thrust caliber flatulance, a human has no chance of flying on their own. All you can hope for is finding a way to fall a little slower than every other roof jumper before you.
  16. Nov 30, 2006 #15


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    Forget that, too. After 16 or 17 beers and a load of nachos last night, I managed to alienate everyone in the bar... but I still couldn't get off the ground. :grumpy:
    Maybe a worthwhile project would be to explain why humans can't fly without mechanical aid. I'd suggest starting with body density and relative muscle mass.
  17. Nov 30, 2006 #16


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    Make sure and take video when and if you try, I suspect it would be quite hillarious to watch :rofl:
  18. Nov 30, 2006 #17


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    I don't think its anything to do with body density and muscle mass. If those were the problem, we wouldn't be able to fly WITH mechanical aid because we couldn't generate enough power.

    The obvious problem is geometry. Human bodies don't have any parts that can work as a wing.

    For comparison, the heaviest bird which regularly flies long distances (i.e. several kilometers without stopping) is the Mute Swan, with a typical mass of 10Kg and a wingspan of 2m.
  19. Nov 30, 2006 #18


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    That's pretty much it. Most of the relevant muscles are the same in birds as they are in humans, but while our leg muscles are many times larger than our chest and back muscles, for birds it is the opposite.
  20. Nov 30, 2006 #19


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    Sorry, guys; I stated that badly. I meant certain muscles relative to other muscles, as well as to other species. Even with perfect artificial wings attached, I'm pretty sure that a human's chest muscles couldn't develop enough power to overcome the density of the body. I also don't think that a bird with solid bones could either. After all, bats have almost perfect flight adaptation for mammals, and they can't take off from ground level.
  21. Nov 30, 2006 #20


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    In a way it is related to muscle density because of our skeletal systems. Ours are built like tanks compared to a bird's. That also decreases our range of motion and types of motions we can perform.
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