Birds Give a Lesson to Plane Designers

Roland Piquepaille points out a news release from the University of Michigan where researchers are looking to birds and bats for insights into aerospace engineering. Wei Shyy and his colleagues are learning from solutions developed by nature and applying them to the technology of flight. A presentation on this topic was also given at the 2005 TED conference. From the news release: "The roll rate of the aerobatic A-4 Skyhawk plane is about 720 degrees per second. The roll rate of a barn swallow exceeds 5,000 degrees per second. Select military aircraft can withstand gravitational forces of 8-10 G. Many birds routinely experience positive G-forces greater than 10 G and up to 14 G. Flapping flight is inherently unsteady, but that's why it works so well. Birds, bats and insects fly in a messy environment full of gusts traveling at speeds similar to their own. Yet they can react almost instantaneously and adapt with their flexible wings."

Comments

Re:Missing tag.

[calebt3]

***Warning: Hearsay below***

Apparently once upon a time all articles submitted by Roland linked to his blog which linked to the real article (as a way to generate ad revenue, I think). And he continues to take flak for it to this day.
Like I said, this is second-hand from earlier discussions. I was not here when it was happening.

Re:Missing tag.

[amorsen]

Considering that the laws of physics scale uniformly with size (as long as we're talking about objects bigger than a molecule and smaller than a planet) this shouldn't matter. Where do you get this junk from? Mass increases cubically when wing area increases quadratically (and wing span increases linearly).

Were an enormous 11,000kg unladen swallow to exist, it should exhibit pretty much the same characteristics as the 10g swallow, with a slight penalty for increased air resistance. With the slight difference that the 11,000kg swallow would not be able to stand up, much less fly.

Re:It's the people, not the planes.

[vbraga]

Enhancing Aircraft Conceptual Design using Multidisciplinary Optimization, by Dan Raymer.

[PDF] http://www.aircraftdesign.com/RaymerThesisFinalRevLowRes.pdf

Genetic algorithms are a pretty useful stuff, and already in use within aircraft design.

Re:Missing tag.

[jc42]

All this had to work the very first time.

Again, no. The first flocks that set out at random either end up in the ocean, or find land. Those that find land will do this because they had enough food to do this. If each bird in the flock that found land had a random amount of fat, half of them would drop to the ocean, but half would arrive and breed. They would get kids that had genes that would make them eat a little bit more than the imaginary kids from the birds that died. Now repeat for millions of generations, and you'll end up with something quite optimized.

All very true, but you missed the fact that when they started out, Hawaii and Alaska were closer. Today's Hawaiian Islands are the end of a long chain of seamounts that stretch out nearly to the Aleutians, with the seamounts getting older as you go northwest. We don't know when those plovers started this migration, but it was some millions of years in the past, when the end of the Hawaiian chain was one of those older seamounts that was then an island. It could have even been back when the islands were barely offshore from the then supercontinent of Laurasia (though it should be mentioned that we don't know this).

So their ancestors that started this migration had an easier job of it. As the islands slowly drifted out to sea, each generation would be selected for the survivors that were able to make a slightly longer flight.

Environmental change, in this case the effect of a moving geological "hot spot", must be taken into account to fully explain a lot of evolutionary events. That's one way you can get results that seem impossible in today's world, especially things like the colonization of remote islands like Hawaii by species that can't cross the open ocean.