# Is it possible to take off like the birds?

#### meloettakawaii

Q: Is it possible for humans to takeoff from the ground similar to how birds, first run or jump and then flap their wings?

(but not powered by human muscle, since numerous experiments have proven that humans can't really power a machine capable of flapping like the birds)

I've read in aerodynamic books that the easiest way to understand how birds takeoff is simply newton's law:
~ the force generated by the birds flapping their wings down is greater than the gravity on the bird so they literally push themselves off the ground by pushing air down.
~ this of course requires and immense burst of energy

Q2: Do we have a powerful enough motor / actuator / that's light enough (similar to bird's chest muscle) to strap on like a backpack that would allow us to push ourselves off the ground like the birds?

thanks!

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#### Dale

Mentor
The largest known living birds that fly is the albatross, which is nowhere near as massive as a human (< 15 kg vs ~75 kg).

There are fossilized skeletons that look like birds which may have been nearly as massive as humans, but certainly none that we have ever observed to "run or jump and then flap their wings". Such birds, if they could fly at all, may have had extreme difficulties taking off and landing.

#### meloettakawaii

thanks, but we are humans, we invent things that don't exist.
i guess what i really want to know is what exactly are the math calculations behind such a motor/actuator to enable this kind of flight... like just how much torque, and how little weight it has to be to achieve this... and how big the wing span....auaaaah to much questions! my mind is blown!

#### berkeman

Mentor
Q: Is it possible for humans to takeoff from the ground similar to how birds, first run or jump and then flap their wings?

(but not powered by human muscle, since numerous experiments have proven that humans can't really power a machine capable of flapping like the birds)

I've read in aerodynamic books that the easiest way to understand how birds takeoff is simply newton's law:
~ the force generated by the birds flapping their wings down is greater than the gravity on the bird so they literally push themselves off the ground by pushing air down.
~ this of course requires and immense burst of energy

Q2: Do we have a powerful enough motor / actuator / that's light enough (similar to bird's chest muscle) to strap on like a backpack that would allow us to push ourselves off the ground like the birds?

thanks!

It takes large wings and a long takeoff strip in order to get the Human-Powered Aircraft into the air...

#### A.T.

Q: Is it possible for humans to takeoff from the ground similar to how birds, first run or jump and then flap their wings?

(but not powered by human muscle, since numerous experiments have proven that humans can't really power a machine capable of flapping like the birds)
Not really taking off on its own, but holding height for a while under human power:

Q2: Do we have a powerful enough motor / actuator / that's light enough (similar to bird's chest muscle) to strap on like a backpack that would allow us to push ourselves off the ground like the birds?
We do have jet packs that fly for a short time.

#### meloettakawaii

thank for the links berkeman. my first question wasn't about human-powered flight, note the parenthesis. i'll check the 2nd link for some inspiration

#### meloettakawaii

thanks AT. yeah i've seen this before, but its not realistic.., there's no reason to make flight 'human powered', we have plenty of power sources from gas to electricity. Ironman's suit might be a little far fetched, but a set of compact wings + really powerful / light motor/actuators might do the job..

#### A.T.

but a set of compact wings + really powerful / light motor/actuators might do the job..
Something like this?

#### meloettakawaii

yes and no xD... i guess i wasn't clear.. sorry everyone.
idk, people seem to automatically think of wings not moving...
bird wings, they move, there's 2 of them flapping
jet packs lasts for a short time b4 the power is gone, birds can fly for days
i was thinking more of like copying the bird exactly as it is except that the power source is replacing the bird muscle with something more fitting for a 'human bird'

so we would take off like birds, probably a few steps running with a jump, then a sequence of flapping, and then our arms would control the all 6 axis of the wing, with the help of some sort of exoskeleton of course, and the power to flap/control these 2 wings would be ... idk some super strong super light motor/actuator.

#### phinds

Gold Member
yes and no xD... i guess i wasn't clear.. sorry everyone.
idk, people seem to automatically think of wings not moving...
bird wings, they move, there's 2 of them flapping ...
I think your original post was totally clear on that ... I think folks are just spoofing you because of a knowledge-based disbelief that what you are asking for is likely to be possible

EDIT: although, given modern materials it might very well BE possible, although I'd think that if it were, someone would have done it just to show that it can be done and to be the first to do it.

#### meloettakawaii

oh if that's the case then you better go build one, because i'm building it... xD

#### phinds

Gold Member
oh if that's the case then you better go build one, because i'm building it... xD
Uh ... why would I want to build one?

#### meloettakawaii

idk, just imagine a future where we could expand our freedom of travel with a pair of wings. we could go travel whenever wherever. there's no being stuck in a traffic jam in highway. you could live 100 miles away from your work place, maybe up in the mountains because you are sick of the over populated and over polluted cities, but can still get to work in under an hour... no traffic. you can go visit your friends and families in other continents w/o buying a plane ticket or saving up for a vacation, you just exit the door and fly there. you can go explore and experience the rest of the world in person rather than through the computer screen...idk its just freedom.

#### A.T.

birds can fly for days
So can airplanes. Birds use flapping for propulsion because rotating parts are hard to develop biologically. It doesn't make sense to insist on the same mode of operation for machines that don't have those restrictions.

#### phinds

Gold Member
You're dreaming. When I said it might be possible with modern materials, I was thinking of something like an ultra light-weight composite wing structure with something like a 100-ft wingspan (and I don't know that that would be enough).

#### meloettakawaii

So can airplanes. Birds use flapping for propulsion because rotating parts are hard to develop biologically. It doesn't make sense to insist on the same mode of operation for machines that don't have those restrictions.
the level of control you get from being able to maneuver each of the 2 wings is beyond anything even military fighter jets can do, that level of maneuverability is what keeps the bird safe and no need for a parachute. (not saying not to use a parachute, but birds have adapted with the lack of one)

#### meloettakawaii

You're dreaming. When I said it might be possible with modern materials, I was thinking of something like an ultra light-weight composite wing structure with something like a 100-ft wingspan (and I don't know that that would be enough).
exosuits, advance that area and you'll have a robot wing on your back.

#### A.T.

the level of control you get from being able to maneuver each of the 2 wings is beyond anything even military fighter jets can do
There are no birds of the mass of a military fighter jet, or even a human. Model helicopters are more agile than birds of same mass:

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#### meloettakawaii

that's more like a hummingbird

#### Dale

Mentor
thanks, but we are humans, we invent things that don't exist.
Sure, but then I wouldn't call it "like the birds". There aren't any birds massive enough to be comparable.

#### meloettakawaii

Sure, but then I wouldn't call it "like the birds". There aren't any birds massive enough to be comparable.
why are we discussing over syntax, birds flap, can humans take off by flapping?
also flapping means giving the pilot control over each wing surfaces and therefore the fine control over flight characteristics

#### Drakkith

Staff Emeritus
2018 Award
why are we discussing over syntax, birds flap, can humans take off by flapping?
also flapping means giving the pilot control over each wing surfaces and therefore the fine control over flight characteristics
I'm sure it's possible if someone dedicated the time and resources to develop it. It's just not practical.

#### A.T.

that's more like a hummingbird
It moves like one, while being magnitudes heavier. There is no bird of similar weight and agility.

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