Aluula Composites | Episode # 135

[Greenturtle]

I prefer the left to the right , and toby prefers a tube kite

[foilholio]

chop chop

[purdyd]

We’ve been down this road before

viewtopic.php?f=1&t=2316077

But for smaller kites it states:
"Good aerodynamic efficiency, however, while of key importance in larger kites, say 12 meters and up, is not as important in sizes 10 and under. Instead, for smaller kites we place more emphasis on good handling. Ironically, the handling of smaller kites is enhanced by the long, thick leading edge so despised in large kites. Such a leading edge can (a) reduce turning quickness, thus making the kite easier to control, lower speed through the window, which decreases the amplitude of dangerous power spikes while lengthening the power stroke to a more useful duration, and (c) cause the kite to ride deeper in the window, which prevents overflying and excessive surging during gust-lull cycles. For these reasons, we made the LE of the Rhino 9 and 10 as long and thick as was possible, consistent with other design considerations. "

Bill Hansen was a leading edge small as structurally possible proponent

http://switchkitesriders.blogspot.com/2 ... -bill.html

Optimizing Leading Edge Diameter
The most difficult task is optimizing the diameter such that it is just small enough to support the dynamic lifting and bridle loads without buckling under normal pumping pressures and use. The optimal tube will vary substantially between kites of different outline, profile, use and construction (such as segmented or constant curve.) Kites with extremely small tubes tend to be very responsive and fast but lack power in turns due to excessive twisting and can fold during water re-launch. Kites with excessively large tubes tend to be slow and have higher turning bar pressure because they are overly stiff. They can also be hard to water re-launch.

Kite designers have played with the leading edge diameter for years and we’ve had fancy material and fancy bridles.

Again, the ocean rodeo roam has had.a rather large leading edge. In fact the first roam aluula prototypes kept that same size leading edge,

I don’t believe kite designers are all stupid.

But I tell you one thing that has changed, we seldom get designers or industry representatives posting on this forum.

And who can blame them?

[Kiterpep]

A larger tube diameter basically leads to a thicker airfoil.

No, a tube is not an airfoil.

Airfoil thickness directly translates into more lift.

No. An airfoil with no thickness can have high lift. How thick is the fabric on a kite? Point proven.

In low-speed applications, you will see many thick airfoils, which allow more lift even when the wing moves slowly

No. You don't understand what it is on your so called thick airfoil that is producing the high lift. It is the AoA and camber. Needless to say kites are not fixed and can move independent to the rider. Trying to limit the speed of the kite by having a high minimum drag through extra thickness is... incredibly stupid. But hey hello all to those kite designers, Durrdedurrdurr.

This increases the stall speed drastically.

You mean reduces, but you are wrong.

Furthermore, thinner airfoils can have worse stall characteristics.

Nope wrong again.

All this aside from the structural benefits you mention.

Well congratulations, 1 out 10 ain't bad!

A thinner leading edge is not necessarily leading to higher performance especially in light winds.

O dear well what can I say! Are you a kite designer? Or some how associated to a brand? Have input designing kites? Got this knowledge from a kite designer? Too many guesses I know. You are a kite designer aren't you. You little rascal you making shitty designs. Now go stick a chickenloop up your ass, right up there. Feel good? Ok now give up designing kites please. Thanks.

You should maybe read a paper like this before you claim you know what you're talking about: https://onlinelibrary.wiley.com/doi/pdf/10.1002/we.2329

The leading edge of a tube kite creates a wake flow that basically acts like a virtual airfoil.

This is quite a good explanation about the wing thickness effect on lift and stall: https://aviation.stackexchange.com/ques ... namic-lift

And indeed, I meant reduces stall speed, sorry for the typo.

Finally, I am not a kite designer, but I do have a degree in flight performance and now am working with kite designers on a daily basis.

[madworld]

I loved and always promoted the idea of less weight and more rigidity. Aluula hopefully is that kite, but for over 5-6 years we've already had a much lighter, cheaper and faster turning kite - the BRM Cloud.

10m Aluula - 5.1lbs
10m Cloud - 4.3lbs

A pound lighter. Based on review vids, a good bit faster turning and drifting too. Clouds are almost religiously loved by pretty much every non-race foiler out there, including myself. Yet mainstream reviews for Clouds barely exist, outside of this forum. I don't mean to bark on Aluula at all or turn the discussion to the Clouds. Quite the opposite - major hopes for OR and will be first in line to demo it. It just seems strange that how much hype is going to Aluula tech vs. something we've had for years that's proven to work.

Cloud kites are strut-less and have a small wind range, this Aluula kite has a tremendous wind range and three struts, a very different style of kite. The cloud kites size labeling is weird too.

[Greenturtle]

I loved and always promoted the idea of less weight and more rigidity. Aluula hopefully is that kite, but for over 5-6 years we've already had a much lighter, cheaper and faster turning kite - the BRM Cloud.

10m Aluula - 5.1lbs
10m Cloud - 4.3lbs

A pound lighter. Based on review vids, a good bit faster turning and drifting too. Clouds are almost religiously loved by pretty much every non-race foiler out there, including myself. Yet mainstream reviews for Clouds barely exist, outside of this forum. I don't mean to bark on Aluula at all or turn the discussion to the Clouds. Quite the opposite - major hopes for OR and will be first in line to demo it. It just seems strange that how much hype is going to Aluula tech vs. something we've had for years that's proven to work.

Cloud kites are strut-less and have a small wind range, this Aluula kite has a tremendous wind range and three struts, a very different style of kite. The cloud kites size labeling is weird too.

Weigh posted there for aluula 10m is wrong-
Aluula 10m 1.9kg (4.2lbs)
Same weight as strutless cloud

[windmaker]

I loved and always promoted the idea of less weight and more rigidity. Aluula hopefully is that kite, but for over 5-6 years we've already had a much lighter, cheaper and faster turning kite - the BRM Cloud.

10m Aluula - 5.1lbs
10m Cloud - 4.3lbs

A pound lighter. Based on review vids, a good bit faster turning and drifting too. Clouds are almost religiously loved by pretty much every non-race foiler out there, including myself. Yet mainstream reviews for Clouds barely exist, outside of this forum. I don't mean to bark on Aluula at all or turn the discussion to the Clouds. Quite the opposite - major hopes for OR and will be first in line to demo it. It just seems strange that how much hype is going to Aluula tech vs. something we've had for years that's proven to work.

Cloud kites are strut-less and have a small wind range, this Aluula kite has a tremendous wind range and three struts, a very different style of kite. The cloud kites size labeling is weird too.

Weigh posted there for aluula 10m is wrong-
Aluula 10m 1.9kg (4.2lbs)
Same weight as strutless cloud

Aluula though makes your wallet much lighter.

[Daversj]

Finally, I am not a kite designer, but I do have a degree in flight performance and now am working with kite designers on a daily basis.

7E4BF091-5E5A-4EA8-B56F-7F60C3F3CFDF.gif (1.27 MiB) Viewed 995 times

..........But Foilhulio did stay at a Holiday Inn Express last night.

[iriejohn]

Great to see a company really doing something innovative

Couldn't agree more. It's amazing how so many who have never flown these kites are naysayers and furthermore diss what is more likely than not the beginning of a new technology which will transform kiting. Just loving the Luddites.

[iriejohn]

I don’t believe kite designers are all stupid.

Foilholio does!

But I tell you one thing that has changed, we seldom get designers or industry representatives posting on this forum.

And who can blame them?

Nobody.