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Old 09-18-2008 | 08:43 PM
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OffroadBEAR
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From: Wichita, KS
Default RE: Zero speed landing possible ?

Okay, I think I understand you a little better now. Its not that I am trying to hassle you or anything, but a little reading into fundamental aerodynamics goes a long way.

Basically, an airplane has to have forward "freestream" velocity to fly, that is, it must have air flowing over its wings. A wing just sitting there in space does not generate lift. I guess you could call it a landing, but if a plane's forward speed is reduced to zero, its wing stops generating lift and it gains velocity downward resulting in a crash (landing of sorts). If it pitches forward whilst moving downward, it can generate lift again, but pitching downward changes the flow velocity in relation to the wing.

A bird on the other hand is an entirely different animal (pun intended). A bird's wing has camber like an airplane's wing, but this camber can be affected by the bird's muscular movements. The angle of attack of the bird's wing is also highly variable depending on muscular movements. An ornithopter only replicates the up and down motion of a bird's wing, but does not include the forward-backward motion and rotational motion of a bird's wing, nor does it replicate the muscular movements of a bird.

I would think it is highly improbable that you could accomplish a robotic bird that is actually capable of flying due to the amount of equipment you want along with the equipment needed to flap wings. Wind tunnel models have been made replicating all three movements of an avian wing, but to my knowledge, a working, flying robot bird has not been made yet (I could be wrong), so here's your chance.

Get the book "Model aircraft Aerodynamics."