High Pressure kite by Bruno Legaignoux

[BWD]

More than the amount of pressure, i am interested in the use of a tube on the top of TE to support TE and as a reflex former to potentially stop overflying etc. That’s innovative, cool if it works well.

[Toby]

I think many of us would be happy already, if the diameters were 2/3 of the diameters today.

Pumping an 18 every time I can only agree

[grigorib]

I think many of us would be happy already, if the diameters were 2/3 of the diameters today.

Less floatation, way less structural rigidity, questionable benefits.
Also kite sizes are going down, specifically for freeride foiling (and for boosting 9 is the sweetest size), 11m is a "big" wing nowadays and pumping up a 4m or 5m-7m-9m is not that big of a deal.

Even as of weight reported by Bruno - my 3 strut 8m Rally 2012 weighed 2.4 kg, and single-strutted Clouds are lighter than that. But I agree on one thing - less of heavy material adds to low end and "pocket" kites, just as "pocket boards are awesome

[tilmann]

way less structural rigidity

Keep in mind that future tubes will have 5 times more pressure in than today !

[grigorib]

way less structural rigidity

Keep in mind that future tubes will have 5 times more pressure in than today !

Of course you need to pump smaller diameter harder.

But diameter matters for rigidity. Remember how moment of inertia for a given object cut shape is a key in “strength of materials”. If you combine all the material mass of I-beam or a pipe into a rod it won’t hold crap. It’ll be only as strong for lengthwise pull, but not for bending nor twisting. That’s why inflatable SUPs are fat.

Problem of kitesurfing is that all better engineers are employed building airplanes and tanks and we get community college graduates design stuff which should be climbing grade simple and climbing grade reliable. Even when inventors are geniuses they make their prototypes pretty and let amateurs do production. It took damn 3 decades to create a seatbelt-buckle-click chickenloop (thank you Ozone!) and there’s barely a simple/short foiling production chickenloop yet. What a shame for all of us.

I have huge appreciation for work inventors and companies do for us all but there’s huge list of failures and plain questionable solutions driven merely by hype and greed. Maybe if we were paying a bit more for gear the situation would be different

[Toby]

Problem of kitesurfing is that all propehr engineers are busy building airplanes and tanks and we get community college graduates design stuff which should be climbing grade simple and climbing grade reliable. Even when inventors are geniuses they make their prototypes pretty and let amateurs do production. It took damn 3 decades to create a seatbelt-buckle-click chickenloop (thank you Ozone!) and there’s barely a simple/short foiling production chickenloop yet. What a shame for all of us.

might change now with NTG into the game...

[tilmann]

@ grigorib: inflatable SUPs have 15 PSI but future kites will have 60 PSI and more ...

[grigorib]

@ grigorib: inflatable SUPs have 15 PSI but future kites will have 60 PSI and more ...

Pump-in pressure in air-structure stadiums is 0.01 psi max and it holds tons of material because area is huge.
Pressurize a 1/4” copper pipe at 300 psi inside and I’ll still bend it easily.
But regardless - moment of inertia of object cut shape defines rigidity for twist and bending and anything thin will probably need way more bridle suppprt, just like foil kites do.

[tilmann]

moment of inertia of object cut shape defines rigidity

mmmh, can you explain this ?

[JakeFarley]

Moment of inertia is generally the cross section of the load bearing element. A larger diameter tube is more rigid than a smaller one given the same thickness, internal pressure and material.