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 Post subject: Re: Changing lengths of lines (Ozone kites)
PostPosted: Sat Nov 02, 2013 8:26 pm 
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lobodomar wrote:
"

Thirdly, what do you mean by "camber?" Although I have heard this word before, I am not 100% clear on its meaning.

"

Camber is the curvature of the profile along the chord. Some poster said above that apparent wind kites are higher cambered, but its quite the opposite. High camber (deep profile) means power at low speeds, but way too much drag preventing the attainment of higher speeds.


Not true !!!

Higher cambered kites dont have more drag - they actually have lower drag, at the same high lift coefficients :thumb:

Of course they also got power at low speeds, because of the higher max lift coefficient.

And if these kites are high AR (needed, otherwise they WILL have a huge amount of drag at high L.C.), they will generate an enourmous amount of power when apparent wind strikes - that being when ridden fast or flown in sinus :naughty:

An example is the North Dyno.
High Camber - High AR.

This kite is a pure power machine, when you ride it fast, and the apparent wind kicks ass on such a kite - GREAT !!!

Whereas a low cambered wavekite, low AR - will not gain much if flown fast, compared :(
This is the whole idea of a wavekite though - that it should never have powerspikes at all, like the apparent wind kites has :nono:


I think some are confused about the fact that low cambered kites (with no power), NEED to be flown faster, in order to GET any power, for the same size.
But this is just an unfortunate mishap, and not something wanted - unless you ride waves.


If you exaggerate the camber, you might get even more low end at low speeds, but not max L/D and not very efficient.
When you reach this point, yes, the apparent wind will not have the same beneficial effect as maxed L/D kites will, that is true.

But IMO most kites are far from that camber - because we need way more range and depower in general in kitesurfing.

A low cambered kite has a huge amount more wind range than a high cambered one - but of course its lowend is much worse.
Because the high cambered kite will still pull and have drag even with fully slack lines - whereas a totally flat kite (no camber at all and a thin LE) could almost be held in infinite high winds (and still be able to lift somewhat, believe it or not)

8) Peter


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 Post subject: Re: Changing lengths of lines (Ozone kites)
PostPosted: Sun Nov 03, 2013 10:51 am 
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Maybe what you call higher cambered is what I would call moderately cambered.

It's true that some camber is important to achieve max L/D. But any camber higher than that will make a kite less and less usable as an apparent wind kite, while still usable at low flying/travelling speeds.

The fact that a wave kite should be low cambered in order to prevent power spikes doesn't mean that race kites are higher cambered than for example wakestyle kites.

Grunty kites (which are ideal for wakestyle) have what I would call "high camber", and are definitely not apparent wind kites.


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 Post subject: Re: Changing lengths of lines (Ozone kites)
PostPosted: Tue Nov 05, 2013 12:09 am 
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mmeyers12 you are exactly on target about how line length works with slower and faster kites.

Now it is true that shorter lines make the kite feel more responsive and quicker.

And it is also true that longer lines make the kite feel soggier and less responsive.

Right. So the natural inclination is when you have a very slow kite you want to "speed it up" by having shorter lines and if you have a very fast kite you want to "slow it down" by having long lines.

But it doesn't work! As you found out.

When you have a really slow kite it means it takes a really long time to complete a turn, and if you give it a lot of line it means you don't have to yank like the devil to get it to complete an entire turn.

By contrast if you have a very squirrel evil hornet tempered kite, if you put it on long lines it will spin there like a demented bee, but if if you put this devil on short lines it will feel incredibly quick but a lot more controlled.

so yeah, slow kites work better on long lines, quick kites work better on short lines, and medium tempered kites can improve in performance on the 25 meter lines like you noticed.

Just my opinion on the lines.

I think most people only modified the bar width when they have a slow kite, they give it a wider bar, and when they have a fast kite they get a short bar, but you can also help improve the handling by changing the line lengths. You want to experiment with both to find the sweet spot.

As for your catalyst try it again on the 20 meter lines but this time try a wider bar 55cm or more.


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 Post subject: Re: Changing lengths of lines (Ozone kites)
PostPosted: Thu Nov 07, 2013 5:40 pm 
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lobodomar wrote:
"

Thirdly, what do you mean by "camber?" Although I have heard this word before, I am not 100% clear on its meaning.

"

Camber is the curvature of the profile along the chord. Some poster said above that apparent wind kites are higher cambered, but its quite the opposite. High camber (deep profile) means power at low speeds, but way too much drag preventing the attainment of higher speeds.


Well put. I have a 8 10 12m kites, two bars, one 20m one 23m lines, and I swap around between them. Longer lines, longer swoop, so get's going in lighter winds. As an example, if I struggle to get going on my 10, rather than changing up, I use the longer line bar. Once going, the kite stays powered (apparent wind)


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