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In a form off a kite can wind be redirected like a sail boat in any direction? Can cross winds around a jet stream be helpful in speed in such a design?

Steve V.
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  • You can't sail a sailboat directly up wind. Winds don't usually oppose, so what do you mean by crosswind? – Ron Beyer Feb 22 '16 at 20:09
  • related: http://aviation.stackexchange.com/questions/24420/can-a-foot-ball-field-size-kite-carrying-person-s-fly-around-the-world-by-ridi –  Feb 22 '16 at 20:22
  • Boats have a keel and contact with water. – Steve Feb 22 '16 at 21:22
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    Hi Jen, I modified the title of your question. Aviation.SE is a little bit different than most web sites. Around here, we encourage you to repeat your actual question in the question title. If I misunderstood what you were asking, please feel free to re-edit. – Steve V. Feb 23 '16 at 01:50
  • @RonBeyer: It depends on the type of sail you use :D – slebetman Feb 23 '16 at 02:01
  • @slebetman Do you have any references for that? I can't find any kind of sail that can go directly upwind without tacking. – Ron Beyer Feb 23 '16 at 03:22
  • @RonBeyer: A windmill sail can go upwind. Though not sails in the traditional sense because the windmill is used to drive a propeller it is technically sailing. It's not so much the propeller that's pushing the ship - it's the interaction between the windmill and the propeller that extracts energy out of the shear forces between the wind and the water - the same way a normal cloth sail work with the keel. – slebetman Feb 23 '16 at 03:39
  • Plane can. Look dynamic soaring. – Andrius Feb 23 '16 at 07:33

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Why do you need a kite? A glider is much better suited to the task.

Again, nature has invented this long ago. Albatrosses use a technique called dynamic soaring to cover wide distances over water, using the windshear close to the surface.

Humans have tried to imitate this with gliders, albeit with limited success. The few who tried it could indeed stay in the air by harvesting energy from windshear, but the dynamic loads (up to 4 g) were too much to do this over an extended time.

Peter Kämpf
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  • a plane cannot bend its wings to maximize redirection of like a sail boat. –  Feb 25 '16 at 04:16
  • @Jen: Redirection of what? If you have discovered a new law of physics, we would like to hear about it! – Peter Kämpf Feb 25 '16 at 22:26
  • a bird can bend one wing in on direction to redirect wind downward from a cross wind some what like a sail gliders can do that but a kite can. –  Feb 26 '16 at 02:06