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Re: Pulsion 18m

Posted: Sun May 27, 2018 9:02 pm
by Regis-de-giens
I know and defend this idea for years and years ... i would like to get the opinion (I mean confirmation...) through a back to back test for sceptical people.

Re: Pulsion 18m

Posted: Mon May 28, 2018 2:33 am
by jakemoore
Nem0 wrote:
Sun May 27, 2018 8:02 pm
Zenith parking and handling depends on less weight per squaremeter!
But also lift and drag, the forces that tense the lines. The same kite in heavy cloth or when wet obviously flies worse. But a kite with more pull can counter more weight.

Re: Pulsion 18m

Posted: Mon May 28, 2018 6:22 am
by Sombra
....but will Backstall easier especially if you try to steer the kite for the powerdive. ( Or not?)

Re: Pulsion 18m

Posted: Mon May 28, 2018 3:12 pm
by foilholio
Not. More lift from either less weight, or higher lift profile, i.e. more camber, will backstall less.

Maybe Regis is inferring some autozenith trait that would give better zenith.

Re: Pulsion 18m

Posted: Mon May 28, 2018 8:07 pm
by Regis-de-giens
@foilholio: I do not want to get too deep in general kite design question; I just wanted to bounce on following remark
Nem0 wrote:
Sun May 27, 2018 8:02 pm
Regis-de-giens wrote:
Wed May 23, 2018 11:55 pm
Can you compare the marginal wind flight of Pulsion vs soul at the zenith ? When working the kite ? Even if even with same kite model, 12m2 is easier to keep in the air tat 18m2.
Do you mean comparison 18m Pulsion with my 12m Soul or 18m Soul?
Zenith parking and handling depends on less weight per squaremeter!
... and say that I agree with Nem0 that the main parameter to kept foil kite in the air in low wind is weight per square meter (more precisely weight by projected area) ;
... and to comment Jakemoor: indeed more lift will lead to better hanging in light wind, however lift is (overall) proportional to area ... which is (overall) proportional to weight ... so in detriment of light wind ... so (assuming you have set the camber at the optimum) the main way to lower the minimum wind to fly the kite is to get a light kite / projected sqm like cloth weight or flatten the profil.

... sorry for the out-of-topic, we should stick to Pulsion feed-back for readability of the post

Re: Pulsion 18m

Posted: Mon May 28, 2018 8:37 pm
by Nem0
For a comparison I make some pics of the 12m Flysurfer Soul...
Profile... similar to Pulsion.
Screenshot_20180528-212952_Gallery.jpg
Leadingedge... lot thicker than Pulsion.
Screenshot_20180528-213015_Gallery.jpg
Inside direction to TE... 2 big ellipse wholes.
Screenshot_20180528-213035_Gallery.jpg
Inside direction to LE... 1 big ellipse whole.
Screenshot_20180528-213023_Gallery.jpg

Re: Pulsion 18m

Posted: Mon May 28, 2018 8:40 pm
by Nem0
Nem0 wrote:
Sun May 27, 2018 8:02 pm
Regis-de-giens wrote:
Wed May 23, 2018 11:55 pm
Can you compare the marginal wind flight of Pulsion vs soul at the zenith ? When working the kite ? Even if even with same kite model, 12m2 is easier to keep in the air tat 18m2.
Do you mean comparison 18m Pulsion with my 12m Soul or 18m Soul?
Zenith parking and handling depends on less weight per squaremeter!
@ Regis-de-giens
Do you mean comparison 18m Pulsion with my 12m Soul or 18m Soul?

Re: Pulsion 18m

Posted: Mon May 28, 2018 9:24 pm
by kitexpert
Regis-de-giens wrote:
Mon May 28, 2018 8:07 pm
... and say that I agree with Nem0 that the main parameter to kept foil kite in the air in low wind is weight per square meter (more precisely weight by projected area) ;
I must say no. Because if kite has very low or even negative camber it does not produce lift at all at low AoA's and will not keep in the air, almost no matter how light weight it is constructed. Airfoil has a significant role how kite behaves in low winds.

Compared to Soul Pulsion is lighter but if Soul does not stay in the air conditions for kitesurfing are hopeless for 99.5% of kiters, even for hydrofoilers.
When snow kiting I can keep a LEI in the air perhaps to 4-5kn, but then using it for moving it is very difficult. In 6 kn most kites will stay in the air but it is too lame to be useful. 6-8kn snow kite sessions are sometimes nice if weather and surface are great, if not just waste of time.

Because kites have to be usable - meaning to have depower and stability - there is unavoidable compromises to be made. Airfoils are not very efficient and also if structures are simplified for light weight and lower costs it means added drag.

I very much doubt if there is much practical advantage with Pulsion 18m compared to Soul 15m kite. For normal weight kiters foil kites above 15m are too slow, anything but moving the lawn is difficult and risk to be overpowered is big. FS kites have had very good high ends though, I'm sure Soul is not an exception.

It is not at all difficult to design very efficient low wind kite. What is difficult is to design a kite with good usability and wide wind range.
Regis-de-giens wrote:
Mon May 28, 2018 8:07 pm
... sorry for the out-of-topic, we should stick to Pulsion feed-back for readability of the post
Not at all. Pulsion 18 is a kite in which light weight is of highest priority, so discussion of the subject is not OT. Else Pulsion is a kind of "antidesign", it ignores much of the development achieved in last 15 years in foil kites (and PG's).

Re: Pulsion 18m

Posted: Mon May 28, 2018 10:24 pm
by Regis-de-giens
I strongly suggest you once try a Pulsion or even any concept'air kite before saying such non-sense arguments. No one spoke of negative camber obviously. We speak of "average-well-developed" kite of course and I think Benoit Tremblay does not need your advices since the first closed cell kite he did before Flysurfer decades ago.

Sorry to be a bit direct but you should review your light wind basics. End of theoretical discussion for me on this post. Please open dedicated (and precise ) topics if you want, I'll be happy to argue.

Re: Pulsion 18m

Posted: Tue May 29, 2018 6:54 am
by omg
Thanks for Regis etc. for very valuable info contribution!

Can I ask, what is the difference for low wind foiling between the 12m and 18m Pulsion? I have a very big front wing, so would I (78kg, very good kite skills) gain much if at all from 6m bigger Pulsion and loosing a lot at the high end? For Pulsion 12m, is the 32g/32g too heavy or will it fly well?

Thank you!