How its Possible for Bumblebees to fly?

[josephcaritel]

As per Aerodynamics theory, Bumblebees can't fly, prove it how can they fly,
Their wing to body weight ratio is very critical to prove,
And we have not succeeded to do aircraft with flapping wings.
http://library.thinkquest.org/08aug/02343/Pictures%20-%20Bumble%20bee/bumble%20bee.jpeg

 

[D H]

As per Aerodynamics theory, Bumblebees can't fly ...

Nonsense. This is an old urban myth that just won't die.

 

[Danger]

The original concept didn't take wingtip vortices into account. Bees' wings don't just flap; they twist.

 

[cjl]

The original concept didn't take wingtip vortices into account. Bees' wings don't just flap; they twist.

The version I heard is that the myth originated when someone didn't take into account the very low reynolds numbers at which bumblebees fly. The aerodynamic principles change quite a bit in this flow regime - viscosity becomes more important, while having a nice, streamlined shape becomes a whole lot less important (especially for the lifting surfaces, such as the wings).

 

[Danger]

The version I heard is that the myth originated when someone didn't take into account the very low reynolds numbers at which bumblebees fly. The aerodynamic principles change quite a bit in this flow regime - viscosity becomes more important, while having a nice, streamlined shape becomes a whole lot less important (especially for the lifting surfaces, such as the wings).

I was unaware of that one, but it seems logical. There is no doubt, though, that the vortices are a major contributor. If you watch extreme slow-motion movies of the wings, you'll see that there is a tremendous "whiplash" imparted by the outer extremity when it snaps around. (The closest analogy that I can think of is the wrist action of a person throwing something.)

 

[rcgldr]

As per Aerodynamics theory, Bumblebees can't fly, prove it how can they fly.

There have been several versions of how this misconception came to be. Wiki article mentions a few possibilities:

wiki_bumblebee_misconceptions.htm

The other issue is the amount of energy consumed by bumblebees or hummingbirds during flight, but they rely on rubber band like muscles (and/or flexible membranes for some insects) that vibrate elastically, reducing the energy required to maintain flight.

And we have not succeeded to do aircraft with flapping wings.

There are motor powered models that fly. Human powered models haven't done very well. Wiki article:

http://en.wikipedia.org/wiki/Ornithopter

 

[A.T.]

There are motor powered models that fly.

May favortite one, because it bends the wings like a bird, not just flaps them:

https://www.youtube.com/watch?v=nnR8fDW3Ilo

Human powered models haven't done very well. Wiki article:

Not self starting, but sustained flight for a while:

https://www.youtube.com/watch?v=0E77j1imdhQ

I'm not sure if they were limited by the stamina or just by the available space to land safely. Human powered propeller planes flew tens of kilometers.

 

[turbo]

As per Aerodynamics theory, Bumblebees can't fly, prove it how can they fly,
Their wing to body weight ratio is very critical to prove,
And we have not succeeded to do aircraft with flapping wings.

Ask the bees. They do not follow our preconceptions.

 

[Danger]

Ask the bees. They do not follow our preconceptions.

And I'd love to hear their version of "the birds and the bees". (It's always been my contention that the bees would be food in that relationship, but maybe that's why I don't have children.)

 

[josephcaritel]

Ask the bees. They do not follow our preconceptions.

Man Got the concept of Flying from Birds, Not by Asking Bro...

 

[cjl]

I was unaware of that one, but it seems logical. There is no doubt, though, that the vortices are a major contributor. If you watch extreme slow-motion movies of the wings, you'll see that there is a tremendous "whiplash" imparted by the outer extremity when it snaps around. (The closest analogy that I can think of is the wrist action of a person throwing something.)

Oh, certainly. Vortices are crucial to bumblebee flight - the wings undergo a stall on every wingbeat which causes the shedding of a fairly sizeable vortex. The very low reynolds number causes this to affect substantially more air than you would otherwise expect given the wing size as well, so the combination of low reynolds number and vortex formation allows flight with a surprisingly high wing loading (when compared to the wing loading of objects at scales we are more used to dealing with).