Photo: Wikipedia, public domain.
Learning from Evolution by Natural Selection
Long before the word 'biomimicry' had been coined, humans were looking at how nature is solving problems and trying to learn from it. When it comes to designing flying machines, studying birds has been the norm as far back as Leonardo da Vinci. But while our feathered friends have taught us a lot about what to do (and what not to do), we have so far neglected the study of flying fish, according to Haecheon Choi, a South-Korean mechanical engineer at the Seoul National University.
Photo: Wikipedia, public domain
Indeed, flying fish are actually better at flying than most people would expect. Some of them can glide for more than 40 seconds, over distances of over 1,300 feet, and at speeds of around 40 mph. Their wings/fins also have pretty decent lift:
As the researchers report in the Journal of Experimental Biology, compared with other flying animals the fish score well at 4.4:1. This makes them more efficient than swallowtail butterflies (3.6), fruit flies (1.8) and bumble bees (2.5). Flying fish are just as effective at gliding as birds that are known for being strong flyers, like red-shouldered hawks (3.8) and petrels (4). Nighthawks (9) and black vultures (17) make more impressive gliders. [...] The experiments also revealed that the fish could glide even farther if they were just 4-5cm from the bottom of the wind tunnel. When the experiment was repeated with a tank full of water in the bottom, the fishes' lift-to-drag ratio rose from 4.4 to 5.5. This, the researchers believe, is caused by the surface of the water smoothing out a vortex of air coming off the flying fish and reducing drag. (source)
Dr. Choi is hoping that we can learn new things from flying fish and apply these tricks to airplanes. If we can increase lift and decrease aerodynamic drag, it woud make planes more fuel efficient and thus greener.
Via The Economist
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