wind density

General discussions about the weather, incoming storms and swell, complaining, why is it always so windy at night etc.

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JL
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Post by JL »

Thanks. Interesting envelope 8)
Thermals are good.
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juandesooka
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Post by juandesooka »

I was clicking around this site, found something interesting. Click on any site, then check out the wind forecast on right side of page:
http://localkitespots.com/kitesurfing/BC

What's interesting is their "Boost" rating:
http://localkitespots.com/boost.htm

They explain the math, probably what MortonMike did for his calculation. The Boost is a percent, multiply it by the windspeed for a temperature adjusted reading. In other words:

Wind speed x (1 + Boost%) = DreadKnot (DKt)

Science!
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windaddiction
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Post by windaddiction »

Are kites flying high enough to get a boost due to the fact they maybe out of the ground level turbalnce? There is a wind gradiant when you get higher up. I know when I used to race sail boats , my instructors would lose thier minds unles your sail was at the very top of the mast, saying there is more wind speed the higher you go.
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duckbill
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Post by duckbill »

I hope it gets windy soon I'm actually reading this stuff.
like a duck to water
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mortontoemike
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Post by mortontoemike »

I'm trying to work in the orientation of the Nitrogen molecules into the calculation. If they hit the sail end on there is less cross sectional area than if they strike the sail side on ... hmmmm ...
Last edited by mortontoemike on Tue Sep 10, 2013 10:36 am, edited 1 time in total.
I wish my TOW was longer!
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abetanzo
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Post by abetanzo »

I second the height of a sailboat's main helps.... the bigger boats with height and sail area totally generate their own speed in the light stuff!
with kites the maneuverability would create even more pull in colder air....

although I did hear if you're racing at Nitinat keep the kite low! but I can understand that would generate more pressure on the fins etc to drive you up wind more...
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windaddiction
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Post by windaddiction »

So what is the practicle limit to line lenghts?
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JL
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Post by JL »

1. Launch area 2. line drag 3. As the line length increases the kite feels less responsive BUT the sining creates a massive power stroke. Try flying a kite @ different heights each session & you will find the wind changes from surface to the peak of the arc. Some times the surface has more. 8) Some times the wind is better 'up top' 4. Take lines off a bar & double your lines on another 8)
Thermals are good.
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