Contact   Imprint   Advertising   Guidelines

Tip stalling and flying line tension

For all foil kite riders
Herman
Very Frequent Poster
Posts: 553
Joined: Tue Jun 04, 2019 7:09 pm
Style: My Own.
Gear: SLE, foils and C kites, TTs, Directionals, Landboards, Buggy.
Brand Affiliation: None
Has thanked: 66 times
Been thanked: 116 times

Tip stalling and flying line tension

Postby Herman » Wed Apr 08, 2020 12:24 pm

When flying a kite across the window, generally I have allowed the top steering line and overall sheeting requirement to dictate the overall tension in the lines and this usually leaves the bottom steering line fairly slack. However, I recently acquired a very old Montana, a lively spikey kite, and the state of its bridle makes it prone to luffing. When flying towards the edge of the window the bottom half of the kite will start to luff if their is little tension in the bottom steering line. As previously stated, the kites I normally fly do not require much attention to bottom steering line tension and so I am finding this old kite interesting and fun to fly.

Before I start tuning the bridle, I would be interested to know if anybody else had come across a similar observation with a modern high performance foil?

Jyoder
Medium Poster
Posts: 189
Joined: Thu Jul 20, 2017 8:31 pm
Gear: Stringy Foil and DIY board
Brand Affiliation: None
Has thanked: 0
Been thanked: 19 times

Re: Tip stalling and flying line tension

Postby Jyoder » Wed Apr 08, 2020 5:17 pm

This happened on my Sonic2 when I played with the mixer and increased camber too much. Reducing camber fixed it.

Herman
Very Frequent Poster
Posts: 553
Joined: Tue Jun 04, 2019 7:09 pm
Style: My Own.
Gear: SLE, foils and C kites, TTs, Directionals, Landboards, Buggy.
Brand Affiliation: None
Has thanked: 66 times
Been thanked: 116 times

Re: Tip stalling and flying line tension

Postby Herman » Wed Apr 08, 2020 6:00 pm

Thanks jyoder I thought that might be the case. I am not going to rush tuning this old Montana as I want to experiment with flying it in this condition for a while. Its only a 5m and land boarding in 16-18 knots the bottom half just starts to tuck if I let the bottom steering line go slack but you can stop it luffing with slight tension and if you are delicate you can do it gently enough to not steer it down or need to oversheet the top steering line. Don't think this setting has much practical use and it makes one handed difficult but it might make my bar handling more sensitive. It is also giving me practice handling complete luffs and reinflation back in the power zone when losing it.

kiteykitekite
Frequent Poster
Posts: 272
Joined: Sun Mar 08, 2020 10:41 pm
Kiting since: 2020
Gear: Core kites
Brand Affiliation: None
Has thanked: 56 times
Been thanked: 32 times

Re: Tip stalling and flying line tension

Postby kiteykitekite » Thu Apr 09, 2020 1:11 am

It's normal for any foil kite to collapse, it can be fixed. Like Jyoder said reduce camber. Do so by lengthening Z say 10cm.

Herman
Very Frequent Poster
Posts: 553
Joined: Tue Jun 04, 2019 7:09 pm
Style: My Own.
Gear: SLE, foils and C kites, TTs, Directionals, Landboards, Buggy.
Brand Affiliation: None
Has thanked: 66 times
Been thanked: 116 times

Re: Tip stalling and flying line tension

Postby Herman » Thu Apr 09, 2020 10:11 am

As you say foil kites do collapse as a normal event, and as the kite is old, shrinkage at Z is almost bound to have occurred. What surprised me was the way I seemed to be able to control the onset of luffing with rear flying line tension which, as yet, l do not fully understand and I do not think it is just AOA keeping it from the window edge. If I can, I will try to see if the gentle rear flying line tension is pulling out camber, I will try also, to observe what the expected short Z is doing to canopy shape from the top half of the kite.

It will also be interesting to see how much, or maybe, how little drive is being delivered from the bottom half of the canopy. You can easily ride with a slack bottom steering line but I have never bothered to feel how much tension there is on the bottom center line compared to the top one. Is there something for the racer to optimize here - can you tell that I am only allowed out for an hour a day!!!!!!!!!! Can't even get the materials to build a couple of mini ramps for the garden!!!!!!!!.....................

Still a lot lot lot lot lot..............better than being stuck and bombarded in a muddy trench!!

Jyoder
Medium Poster
Posts: 189
Joined: Thu Jul 20, 2017 8:31 pm
Gear: Stringy Foil and DIY board
Brand Affiliation: None
Has thanked: 0
Been thanked: 19 times

Re: Tip stalling and flying line tension

Postby Jyoder » Thu Apr 09, 2020 11:50 am

kiteykitekite wrote: It's normal for any foil kite to collapse, it can be fixed. Like Jyoder said reduce camber. Do so by lengthening Z say 10cm.
In my case it was mixer adjustments of B and C vs A that caused the behavior.
These users thanked the author Jyoder for the post:
Herman (Thu Apr 09, 2020 12:45 pm)
Rating: 8.33%

kiteykitekite
Frequent Poster
Posts: 272
Joined: Sun Mar 08, 2020 10:41 pm
Kiting since: 2020
Gear: Core kites
Brand Affiliation: None
Has thanked: 56 times
Been thanked: 32 times

Re: Tip stalling and flying line tension

Postby kiteykitekite » Thu Apr 09, 2020 4:04 pm

Yes there is more than one way to change camber, adjusting B or A is not the right way.

Jyoder
Medium Poster
Posts: 189
Joined: Thu Jul 20, 2017 8:31 pm
Gear: Stringy Foil and DIY board
Brand Affiliation: None
Has thanked: 0
Been thanked: 19 times

Re: Tip stalling and flying line tension

Postby Jyoder » Thu Apr 09, 2020 9:22 pm

kiteykitekite wrote:
Thu Apr 09, 2020 4:04 pm
Yes there is more than one way to change camber, adjusting B or A is not the right way.

Then why is B and C easily adjustable on the Flysurfer sonic2 mixer but not Z?

kiteykitekite
Frequent Poster
Posts: 272
Joined: Sun Mar 08, 2020 10:41 pm
Kiting since: 2020
Gear: Core kites
Brand Affiliation: None
Has thanked: 56 times
Been thanked: 32 times

Re: Tip stalling and flying line tension

Postby kiteykitekite » Fri Apr 10, 2020 1:26 am

Because they assumed wrongly it was the best way to do it. The same BC adjustment has been on Flysurfers for I think nearly 2 decades. Better experience has been gained in those 20 years.... Armin is working on a new mixer, hopefully he does it right. It would probably be better to have no adjustment than B and C. It is definitely better to have just Z than B and C. Z and C is all you need for the profile/camber adjustment. You do need to adjust B ,or the pulley travel length, to maintain or alter the depower limit. I think it would probably be best to have no B adjustment and instead just have a stopper knot or adjustment on the pulley line/s. Adjustable pulley lines would probably be good. Armin has a simple adjustment method that will make the mixer much better.

viewtopic.php?f=197&t=2392205

Herman
Very Frequent Poster
Posts: 553
Joined: Tue Jun 04, 2019 7:09 pm
Style: My Own.
Gear: SLE, foils and C kites, TTs, Directionals, Landboards, Buggy.
Brand Affiliation: None
Has thanked: 66 times
Been thanked: 116 times

Re: Tip stalling and flying line tension

Postby Herman » Fri Apr 10, 2020 9:47 am

^^ Unless you are returning things to spec tuning a bridle is going to be a bit of an art form. Certainly it seems sensible to leave A alone as this, maybe, the least shrunk and it is the obvious new datum. It is also easy to extend that argument to B as well, all be it without the same conviction.
That leaves adjusting Z and C, sounds plausible and thank you kiteykitekite. Would be interesting to set one up in a big wind tunnel to check these things out as I can also see the obvious argument for adjusting the middle of the bridle if you want to effect camber.


Return to “Foil Kites”

Who is online

Users browsing this forum: bragnouff and 3 guests