Re: Foil Kite folding in half when going upwind!?
Posted: Mon Jul 09, 2018 11:18 am
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Really? Single skins can fly further in the WW when slightly sheeted in. This is because when fully depowered there is so much drag from the unsupported and flapping part of the kite.foilholio wrote: Situation in foil kites exist where bar is pulled in but AoA is reduced.
? When depowered kite seeks the AoA in which it wants to settle. If kite is stable enough, it will then fly mostly or fully on A lines, all other line rows are slacking.foilholio wrote: The kite designer has spent much effort finding the correct limit for B
I mean really? You switch positions just like that?kitexpert wrote:Good points from evan and foilholio.
Yes but you will also find Z will shrink more still in those areas. Effect of A shrink there does though amplify the problem of a shrunken Z. The problem of shrink exists on all lines to kite. It is biggest on the rear of the kite being rear lines and rear bridles. The order of most shrink to least goes simply Z,C,B,A . The shrink would most likely be caused by either lower forces there or less time with force or both. Bridle shrink tends to stay in ratio except for Z. Span wise shrink is an issue, like you mentioned with A.kitexpert wrote: However also A can shrink and especially in the wingtip area where loads in the lines are smaller and where problems quite often exist.
I mean very LEI there, everything is about looks. Z has a large effect on the performance of a kite, I adjust for this. Biggest change is power and upwind.kitexpert wrote:I've always adjusted Z for feel and look
I am not talking just about just window change but an AoA reduction where the kite collapses. You are correct that drag changes window position, but I am talking about a kite with Z shorten more than what the designer intended. Like this with bar in kite then collapses. It makes me doubt your experience with foil kites you have not experimented with a very short Z.kitexpert wrote: Really? Single skins can fly further in the WW when slightly sheeted in. This is because when fully depowered there is so much drag from the unsupported and flapping part of the kite.
Airfoil shape, A position, if solely on A and then also B position and then AB length if on A and B ,define AoA minimum. But also Z could be used but not very practical and also drag as you mentioned.kitexpert wrote: I don't know what "limits" there should be, usually there is no "arbitrary" way to restrict kite AoA range.
I'm not switching anything these things are not black and white. Reasons for problems and cures are quite often complex. However if kite collapses in a situation OP described reducing camber/increasing AoA (limiting lowest AoA) is the fix. There is no harm to do it by stretching A's, and like I wrote effect of it is bigger on wingtips where it is needed usually more.foilholio wrote:I mean really? You switch positions just like that?
If this happens there is something very wrong with the kite. Never happened to me. And why on earth kite wouldn't have collapsed earlier, bar sheeted out? Or is kite so bad bar should be sheeted in all the time?foilholio wrote:Like this with bar in kite then collapses.
No reason to do that. I have not experimented many other nonsense things.foilholio wrote: doubt your experience with foil kites you have not experimented with a very short Z.
Basic kite design parameters. One of them is by far most important, most crucial, others just more or less fine tuning (within sane values). This defined minimum is not a design goal, but a result of chosen parameters (which should be of course in harmony with general type and intended use of kite).foilholio wrote: Airfoil shape, A position, if solely on A and then also B position and then AB length if on A and B ,define AoA minimum.
No. Lenghtening Z can't affect A - BC relation. If you want to adjust A-B relation you must do it between A and B. If you take Z completely away A-B-C are still pulled like before and also presets they had (mixer adjustment positions/designed bridle lengths) of course remain the same.
It makes no sense to worry about some lost depower if kite is so unstable it collapses during the normal use. Some acceptable setup for stability must be found, then depower is what it is for that kite.
Of course it does. How can you be so stupid.kit expert wrote:No. Lenghtening Z can't affect A - BC relation.
Everyone should worry about lost depower, it is not just lost depower but lost range. The kite will stall in the window at higher wind(at lowend) with B not slack enough. It's also the reason users like Pullstrings can't understand how foils fly in 1-2knots. If kite is not tuned correctly this is not going to happen. Because of companies like Flysurfer and stupid people like you giving out this advice no one actually fixes the AB relationship correctly.kit expert wrote:It makes no sense to worry about some lost depower