Would planes be better if they were more like birds?

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nestofdragons

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many airplanes have wings inspired on the seabirds with high aspect ratio. If i recall it right, i have read that several landbirds have the same glide ratio as those seabirds, BUT ... at lower speeds. They have lower aspect ratio which might have advantages in construction. So ... if you go towards landbirds, don't expect high speed applications. I would indeed consider bird inspired wings for low speed flying. For the sunday flyers or the beginners or the ones that land on their feet (a twisted ankle is so easy to get).
 

Tom DM

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JoS

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This thread is a treasure chest of info on bird flight - thanks all! Don't know how i missed this for so long....

I'd like to understand though how a lot of these ideas could aver be applied to human flight and the large Reynolds numbers and wing loading typically involved? My understanding is that wing flapping is efficient when there's an instationary vortex with diameter close to wing chord coming off the upper LE (sorry, can for the life of me not remember the reference :( ); which simply doesn't happen at high Re's.

Likewise i think the only human-carrying aircraft with wing loading close to birds are paragliders and hanggliders - both are somewhat flexible wings, both suck when trying to go fast ;) - but thermal great!

My writ is not intended as any critic of previous posts - i'd love to be proven wrong, and go fly with one of our local wedgetail eagles!

Cheers, Jo
 

Sraight'nlevel

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How about ground effect ? All swans that I saw in 3 days on an island in the sea....were flying in ground effect....and trailing another...saving "fuel".

Is this what the birds can tell us ?
 

addaon

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bird wing is STATIC stabil and controlable !

Not really meaningful to analyze stability of a wing in isolation. Birds (the combination of wing, body, and tail) are generally able to vary their static margin from about +30% to -30% (see Figure 4b of this paper; the whole paper is worth a read); basically all birds are able to transition from positive to negative static stability. Range of stability is a factor in maneuverability, but is not particularly indicative of it.
 
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