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I suppose your instability comes at wingtips, right ? Not a central Leading Edge collapse, could you confirm ?

In the affirmative , we noticed that you can improve stability by increasing the camber, hence shortening A or get B longer. This applies on the wave only and unlike general foilkites.

On your picture i cannot see which line goes directly to A and which goes through the pulley. So you need to attach the briddle going to A (the one without pulley), closer to the bar.

cnski wrote: ↑

Mon Apr 20, 2020 3:50 pm

Finally got to try out my CA Wave 6.5m yesterday in strong, punchy winds. I weigh 110 kg and ride a strapless surf foil. This kite was collapsing alot during my session and I was wondering if my line attachment setting choice was contributing to this? See pic below. Front line attachment on left, steering line attachment on right. Any advice on how to tune this kite to not collapse? Thx!!

I'm not as heavy as you (90-95) but I have also had some issues with an occasional collapse of my 4.5 in gusty winds. Not a major problem since it recovers so nicely but still a bit annoying. You already have it adjusted in a pretty "stable" setting I think. I presume that B is the upper left line which passed through the loop. You can try to make this a bit shorter relative to A by moving it down a bit and larks-heading A above B. B is the yellow line in this pic: This is the recommendtion I got from Mr Concept Air. The problem is that there is a limit to how much you can shorten B to get stability, as the kite starts to stall too much. This was the problem I found with the above setting.

Regis-de-giens wrote: ↑

Mon Apr 20, 2020 7:34 pm

I suppose your instability comes at wingtips, right ? Not a central Leading Edge collapse, could you confirm ?

In the affirmative , we noticed that you can improve stability by increasing the camber, hence shortening A or get B longer. This applies on the wave only and unlike general foilkites.

On your picture i cannot see which line goes directly to A and which goes through the pulley. So you need to attach the briddle going to A (the one without pulley), closer to the bar.

Are you sure about that??? The usual approach to instability in the tips/clapping is to reduce camber, by shortening B. And this is what Ben recommends for this problem.

I was as well very surprised by this method of increasing camber. So i counterchecked with the fried who did that and he confirmed (but this is not my kite and my test, hence still a risk that he did the opposite that my understanding).

BUT , i started accepting this stab improvement fir two reasons:
1- i though Benoit said the same but now you seem to say the opposite ... ????
2- when i asked him in detail what instability happened, i understood that it was quite original : not a LE central collapse like most foilkites, bur a "wing tip" collapse: kite closes in two , wing tip left against wing tip right.

And in this particular case, more camber may help depending on briddle plan.

Best is to test ....

Real stable depowerable kite should be able to fly on A line row only. So every bridle/mixer tinkering advice suggests kite already has some issues with stability. I mean kite itself, the wing. If you have to support kite further back (B-C) it also means some depower is lost, in worst cases very much of it is lost (or actually it wasn't there in the first place).

To think adding camber for more stability is quite same as to eat the cake and still have it. You can ask how much more camber you should have and why this higher camber with more lift and claimed better stability isn't used in that kite already? Why isn't it used in all kites?

In reality there is no such miracle values, only trade-offs and compromises.

Ok, and ????
Setting knots are here for that purpose, set (or reset in case of fabrication tolerance or wear like all kites) the kite at the correct setting for example.

And ok, of course the CA wave is very stable on A only , obviously ! and it is even one of the best if not the best drifting double skin kite, so without rear line tension ....

A lot of riders in our tricky spots here (e.g. Almanarre) used it as their storm kite in 40-45 knots with TT's were even good riders on small LEI complained about their own LEI stability.

So, stable; it IS stable ,one of its main feature... now things can move or require re-setting...

Moreover Stability requirement and "compromise" as you said, depends on spot (level of turbulences or suden gusts , weight of rider (linked to wind range), ect ... no kite is 100% stable in evry harch conditions. So adapting stability requirement to each rider is not a shame. Personally i have not touched my 3m wave and its stability suit me on my spot.

All in all, my friend is a regular foilsurfer in mediterranean gusty conditions and is fan now that he tested this increased camber setting, whatever your theorical view of "unsusefulness" of playing with those settings.

No offence here my dear , just arguing.

Once can experiment indeed.

Just to confirm, Benois said that the problem might be "Maybe is too relax on the B line please test this position on the adjustment knot,,,,Ben" (the pic that I posted with B shortened more than A).

I was thinking that a possible cause might be that the internal strapping between the ribs (the black tape near the lower skin) might be a bit too tight. One fix would be to lengthen it a bit in key cells. Another possible fix would be to make some foilholio/Peter Lynn pleats

viewtopic.php?f=197&t=2392853

The effect of these should be similar to the flysurfer PMA adjusters (so adding some of those might also be an option):

Ok, very low AR kite which is stable on A lines only - if that has stability issues wind is just too poor for kiting. I don't even remeber when I had stability issues with any of my kites, partly it may be because I don't kite in miserable conditions.

Ben's advice seems to be normal shortening B, so decreasing camber not increasing. You can also interpreter tighter B as having more support further back of kite which of course helps against front stall.

merl wrote: ↑

Tue Apr 21, 2020 10:28 am

"Maybe is too relax on the B line please test this position on the adjustment knot,,,,Ben"

Relax can be also lengthern B ... no ? to be confirned (hence more camber ?).

I Just a feedback from real user : more camber works to stabilize in high winds / gusts ; this configuration is quite rare on foil kites often used in light / medium winds, hence new "stability types" to sort out with very small small kites.

Can you precise if the instability is the LE or the kite folding in two from tips ?

Regis-de-giens wrote: ↑

Tue Apr 21, 2020 1:27 pm

merl wrote: ↑

Tue Apr 21, 2020 10:28 am

"Maybe is too relax on the B line please test this position on the adjustment knot,,,,Ben"

Relax can be also lengthern B ... no ?

That's not the way I would read it. And it would not be consistent with the picture.

Can you precise if the instability is the LE or the kite folding in two from tips ?

I can't speak for the OP, but in my experience (and Horst too, from whom I bought the kite) we are talking about clapping rather than front stall. This might just be a case of winds which are too poor - but I am only talking about once or twice an hour on a gusty day..