foil kites slack line

[looowis]

hi,

can you get slack in the lines of a foil kite like you can with an lei?
i.e. will edging hard and popping pull the kite out of the window then give some slack, then regain line tension smoothly?

and when riding waves, will a foil sit in the sky with not a lot of tension in the lines like an lei does.

lewis.

[Pump me up]

Unfortunately, foil kites (aka ram airs) have MUCH more drag than inflatables (i.e. are aerodynamically inferior).

This is one of the reasons Peter Lynn has recently begun production of inflatable kites for kiteboarding. It is the reason other ram air manufacturers such as Flysurfer continually fail in competitions.

Excessive drag causes ram air kites to sit deeper in the window. While good wake-style inflatables are designed to sit deeper in the window, this is achieved by deepening the luff curve; it is not a consequence of aerodynamic inefficiency (drag). Hence, although you can get slack in the lines of a ram air, it is of shorter duration and "sloppier" in feel.

Edging hard and popping is still possible, but once again, it is sloppier, spongier, less predictable, shorter, and harder to control.

The same problems occur with wave riding: Ram air kites drag a lot more, so sit deeper in the window (i.e. sit deeper down the line). Hence, it is a lot harder to cut back against the kite and get as vertical on the wave face. Also, because of excessive inertia, ram airs are much slower and are harder to crank to the position you want them while wave-riding. In addition, ram airs have a tendency to asymmetrically collapse when riding towards them down the line, leading to rare but catastrophic back-stalling into the whitewater.

Ignore the lies: Ram airs are aerodynamically inferior compared to inflatables.

[balugh]

hi,

can you get slack in the lines of a foil kite like you can with an lei?
i.e. will edging hard and popping pull the kite out of the window then give some slack, then regain line tension smoothly?

and when riding waves, will a foil sit in the sky with not a lot of tension in the lines like an lei does.

lewis.

Depends on the foil... My Flysurfer S3 will hang in the air with slack lines and little or no input from me until I catch up to it or it catches up to me. Sometimes in these situations with a LEI the kite will fall out of the sky. The Unity / Psycho IV / S3 are all very different kites though. As different to each other as they are to a LEI. Try a couple...I quite like them although I also fly inflatable kites too (e.g. North Vegas). Flying technique is a bit different but not radically so. And no, there is nothing inherently inferior about the aerodynamics of ram air kites... A well designed wing will work well regardless of whether or not it has a semi - rigid tube in the leading edge....

[s1buell_wl]

hi,

can you get slack in the lines of a foil kite like you can with an lei?
i.e. will edging hard and popping pull the kite out of the window then give some slack, then regain line tension smoothly?

and when riding waves, will a foil sit in the sky with not a lot of tension in the lines like an lei does.

lewis.

Watch some of the FS videos their riders seem to have no issue.
is it equal? no idea.....

Gunner could tell you.

[plummet]

check this vid (not me)

might answer some of your questions

[Bille]

Unfortunately, foil kites (aka ram airs) have MUCH more drag than inflatables (i.e. are aerodynamically inferior).
...

I kite board with an Ozone Edge ---

That being said; I've "NEVER" flown a Para glider with an inflatable leading edge !

Ram airs have LESS drag than a LEI,(( because of the twin skins)) and That is Why
a foil "Needs" to have More square foot of aria than a LEI.

Since a Foil develops it's power with speed ; if you over sheet,( pull in ) and allow the speed
to decrease, the power will in-turn decrease.

SO YES the rear lines will be a bit slack at times.
But when you Do pull in, your replacing the speed with power and the kite will
slow down.

It's a Balance.
A good reference would be : if the wind is so light you can Only do
Down Loops, or the kite will fall out from the sky.
As the kite is going UP the hill...
the lines will be slack.

--Pump me up-- i enjoy your passion, but Ya Need to be careful how you word
things; there are some on this forum with a Lot more experience in aerodynamics
than you .
I Built the HG that i placed on in ACRO

Square Foot for square foot :
**A twin skin has less drag .
**A LEI has More power !

Bille

[jakemoore]

IMO the slack is bigger with Flysurfer Psycho4 than a LEI kite because of how the wingtips fold in when the lines become slack.

One thing about the foils that are great is that the hindenburg problem just isn't there. That is to say, when you go very slack the whole kite deforms and does not fall to the ground so easily due to its irregular shape and also because of the very even weight distribution. This is a plus for wave riding because you have much longer to recover.

But one thing that happens with foils is that it takes longer for the kite to regain its shape and smooth airflow after it goes slack. Since the whole bridle is slack and the kite is depressurized it takes a few extra seconds to get into flying shape. Then the kite needs airspeed to develop power. This gentle development of power is one reason Flysurfer kiters are so comfortable with the hot launch. However IMO it is a disadvantage in waves because if you lose power for a second it takes a little more time to get it back.

[voodoospirit]

Peter lynn arc kites will have slack lines , they behave as a C-shape kite and will have the same behaviour.
if u can have slack lines with bow kites, u can have with pretty much anything on the market.

[snobdr]

Funny because ive never seen a C kite open up untill it inverted.
Slack lines on a PL let the wingtips spread apart, enuff slack and the kite opens untill its completely flat and it inverts.

[DrLightWind]

Unfortunately, foil kites (aka ram airs) have MUCH more drag than inflatables (i.e. are aerodynamically inferior).

Excessive drag causes ram air kites to sit deeper in the window.

If they "have MUCH more drag"
than why in reality high performance foil kites are flying closer to the edge

DrLW