Kitefoil, double skin - single skin Peak/FireFly?

[jakemoore]

I can definitely waterstart easier in light wind with HL7 than Peak5. I tried back to back a year ago. No access to either kite now. I think 5 vs 5 it would be close in favor of the peak. There is no question Peak is a joy to fly.

And if comparing 5m peak to an 8m soul then I can only wonder if the soul was out of tune or on very short lines. I can get out in very light wind on my 8 but again will go bigger for better angles or more lift. I can compare 8 soul to 6 Marabou and would say better bottom and top end but the downwind antics are fun on the single skin.

[Janus]

"Or the smallest Soul in 6 m2, is it a powerhouse that can start in maybe under 9 knots for the average weight on a surf foil?
Or is it an upwind high wind kite that has less low end, but HUGE range?"

Don't know.. never tried it on my surf wing & in low wind.. my Soul 6m is a great foiling kite and it has huge range, used it in 12 kts on my medium front wing, Used it on the Kool in 15kts while learning to tack.. it is a very fun kite and as we know we can screw things up easily while learing new things.. so the easy water relaunch is very handy..
But having some waves and a surf foil.. Peak time nothing comes close.. you can let the Soul drift if you keep it lower in the window at the right moment, time the gybes correct.. but riding (a wave &) the foil relaxed like on the Peak, nope.

[Herman]

When I first moved onto depower foils coming from fixed bridle I felt the depower foils did not produce as much power as I would have expected, ie needed a smaller kite if using fixed bridle. As I learnt to use depower foils more aggressively this gap in size required seemed to diminish but I am not sure it completely closed. I never came up with a decent aerodynamic hypothesis that explained this. Obviously the piloting and flying characteristics are different but does anybody have an explanation of how the aerodynamic properties of the optimal fixed bridle wing and the optimal depower wing might differ; and of course, to keep to the thread how are the aerodynamics different to the single skin?? Hard to imagine that a single skin wing could generate more max line tension than a optimum double skin wing, but just sitting in the window............

[drsurf]

When I first moved onto depower foils coming from fixed bridle I felt the depower foils did not produce as much power as I would have expected, ie needed a smaller kite if using fixed bridle. As I learnt to use depower foils more aggressively this gap in size required seemed to diminish but I am not sure it completely closed. I never came up with a decent aerodynamic hypothesis that explained this. Obviously the piloting and flying characteristics are different but does anybody have an explanation of how the aerodynamic properties of the optimal fixed bridle wing and the optimal depower wing might differ; and of course, to keep to the thread how are the aerodynamics different to the single skin?? Hard to imagine that a single skin wing could generate more max line tension than a optimum double skin wing, but just sitting in the window............

You have to try the Peak4 single skin to truly understand how it feels.

But to get to the physics of why the Peak4 feels so good on a surf foil:

(1) The weight of the popular Peak4 kites, 6m, 5m, 4m & 3m is less than 1kg. The kite drifts like a helium balloon and flies upward as fast as down. The manoeuvrability is only matched by the instant power/depower characteristics.

(2) Being a single skin kite it sits deeper in the wind window compared to a twin skin foil. Although this means less upwind ability, (not a problem with hydrofoils), it doesn't hunt for the edge of the wind window and stall when turning. Being further back in the window gives it similar characteristics to an LEI wave kite but even more so. The kite is more responsive and resistant to stalling not to mention the fabulous drift.

That's the brief technical reason for the difference between a single skin Peak4 and a foil kite like the Soul/Hyperlink. Also the inertia caused by the trapped air in a twin skin foil kite works against it for manoeuvrability. However if you want straight line speed, upwind ability and big floaty jumps, a kite like the Soul is hard to beat. But if you have a hydrofoil of 1000 sq cm or more and want to turn fast and ride even small wind waves the Peak4 can't be beat. Even in the small sizes the Peak4 wind range is impressive.

[Cefirmeza]

"Or the smallest Soul in 6 m2, is it a powerhouse that can start in maybe under 9 knots for the average weight on a surf foil?
Or is it an upwind high wind kite that has less low end, but HUGE range?"

Don't know.. never tried it on my surf wing & in low wind.. my Soul 6m is a great foiling kite and it has huge range, used it in 12 kts on my medium front wing, Used it on the Kool in 15kts while learning to tack.. it is a very fun kite and as we know we can screw things up easily while learing new things.. so the easy water relaunch is very handy..
But having some waves and a surf foil.. Peak time nothing comes close.. you can let the Soul drift if you keep it lower in the window at the right moment, time the gybes correct.. but riding (a wave &) the foil relaxed like on the Peak, nope.

Have you used the 6m on its top end?
What is your weight? Maybe the wind range is even bigger for the lighter riders looking for speed and learning tricks.

[Herman]

Thanks drsurf I think you have described it well. A happy marriage of requirements and characteristics for single skin and hydrofoil. As you said Inertia of the air in the closed cell at ~1.225 kg/cubic meter is not insignificant. It is on my bucket list to try the single skins, long time since C quads.

[Peter_Frank]

Agree fully Herman with the fixed bridle versus depower.

But things might "trick" us it seems?

jakemore, regarding the 5 m2 Peak4 versus a guy on the 8 m2 Soul:
He is not that experienced, and had not used his 8 much, but can foil and carve quite okay, and he is 85-90 kg.
So he took a 12 m2 Soul instead, and we rode at the same time, both having fun.
Same wing size, he 10 kg heavier.

Still, I could not understand how it could be fun with a 12 m2 (he dont jump or tack or go fast or anything), but apparently we both had fun, me on the low end with a 5 m2, but my next was an 8 (back then - thank god for the 6), so way more fun carving around underpowered in supersmall waves with the 5, than powered with the 8.

And having read some of the posts in here, I see the same pattern now and then, those riding double skin kites (not racing) use somewhat bigger sized kites than the Peak4 riders, instead of smaller as one would think, because of more spike and efficiency.

But it COULD simply be difference in not only liking, but also experience? (given we use somewhat the same relative wing sizes and compensate for weight)

Like you say jakemore, you think there would be a slight favor (or equal) Hyperlink versus Peak4 both in 5 m2.

This is what I dont understand, unless the design on purpose is made with less power to gain more range, but not sure this is true...

FRS in 6 m2, how does it compare to a 6 m2 Peak4 in lowend?
It should be better, if a more effective double skin kite, not lower AR.

Unless.... ???

And are there some small monsters with HUGE peak power, that can move the low end?
Like the Nasa and Long Star and others?

All kites are different, so this combined with different liking and experience, could also be the reason we see so many mixed signals regarding kite sizes.

Peter

[tomtom]

Soul 8 is MUCH more powerfull than Peak 5
FRS 9 is slightly more powerfull static and have quite more peak power than Peak 8
Soul 8 is about same power than FRS 9

all from personal direct experience

FRS is better kite than Peak in 8m+ sizes /for hydrofoil/ in everything except static stability /hang in air/

[Janus]

"Or the smallest Soul in 6 m2, is it a powerhouse that can start in maybe under 9 knots for the average weight on a surf foil?
Or is it an upwind high wind kite that has less low end, but HUGE range?"

Don't know.. never tried it on my surf wing & in low wind.. my Soul 6m is a great foiling kite and it has huge range, used it in 12 kts on my medium front wing, Used it on the Kool in 15kts while learning to tack.. it is a very fun kite and as we know we can screw things up easily while learing new things.. so the easy water relaunch is very handy..
But having some waves and a surf foil.. Peak time nothing comes close.. you can let the Soul drift if you keep it lower in the window at the right moment, time the gybes correct.. but riding (a wave &) the foil relaxed like on the Peak, nope.

Have you used the 6m on its top end?
What is your weight? Maybe the wind range is even bigger for the lighter riders looking for speed and learning tricks.

70-72kg, haven't found out the top end.. not on foil or on TT
FS gives range for hydrofoil from 11-28kts and on TT 15-37kts, looks ok. But on 15 kts and TT I would take my 12m..

[Peter_Frank]

Soul 8 is MUCH more powerfull than Peak 5
FRS 9 is slightly more powerfull static and have quite more peak power than Peak 8
Soul 8 is about same power than FRS 9

all from personal direct experience

FRS is better kite than Peak in 8m+ sizes /for hydrofoil/ in everything except static stability /hang in air/

Thanks, that would also be expected, both actually as the FRS has slightly less low end yes, but other advantages.

It must simply be individual differences which size some choose, making it even more difficult to compare.

So we should focus on same sizes, how the Peak4 low end is, compared to double skin kites in same sizes 3-4-5-6 m2.

Or other interesting faster kites.

Peter