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Stall question for high aspect wing in light wind

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lovethepirk
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Stall question for high aspect wing in light wind

Postby lovethepirk » Thu Apr 20, 2017 11:21 pm

What's the consensus on higher aspect wings in the lower wind range in which you can get going. F-14 tomcats takeoff in their highest aspect setup. My 16m NRG(high aspect) stalls like a mother fker in light winds compared to my 17m Contra, but once up to speed my NRG is an animal. Are underwater foils subject to the same degree of stalling that you can experience with kites or not so much? I'm asking b/c it's not like I'm trying to stuff my hydrofoil near in the same angle into the power zone as a kite so I feel the hydrofoils don't experience anywhere near the stalling we see in a kite...but again, I'm a fking newbie and I don't know sheet :roll:

I've heard high aspect foils are actually better in very light winds than fatter ones? There's a brief fine line I'd prefer my 17m Contra, but still I do prefer it in really light wind.

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Re: Stall question for high aspect wing in light wind

Postby matth » Fri Apr 21, 2017 2:26 am

I don't think you can compare the two. Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle


https://www.youtube.com/watch?v=17JRkEC1Egk


http://amzn.to/2kdfGlL
Last edited by matth on Fri Apr 21, 2017 2:39 am, edited 2 times in total.

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Re: Stall question for high aspect wing in light wind

Postby davesails7 » Fri Apr 21, 2017 2:37 am

I wouldn't worry about it :D No matter what hydrofoil you use, you'll be riding in less wind than ever before!

I've ridden almost only high aspect race hydrofoils. You can get going in very light winds with a race hydrofoil. I've seen some posts on here saying that larger wings can get you going a bit earlier, but I haven't tried a larger wing back to back to see the difference.

You got a Delta hydrofoil? Is it the new one or a used one? How old?

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Re: Stall question for high aspect wing in light wind

Postby OzBungy » Fri Apr 21, 2017 2:06 pm

matth wrote:
Fri Apr 21, 2017 2:26 am
I don't think you can compare the two. Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle


https://www.youtube.com/watch?v=17JRkEC1Egk


http://amzn.to/2kdfGlL
You had better watch the video and read the book again. I think you missed something.

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Re: Stall question for high aspect wing in light wind

Postby Peter_Frank » Fri Apr 21, 2017 2:35 pm

Are you asking about high AR kites or high AR foils (wings) or both ?

Any (of them) high AR will be more sensitive to sheeting or foot pressure, but perform better so will be able to ride in less wind/speed.

It is the rider (error) when they stall, both of them, not the AR (all other parameters equal).

A low AR will need a tad more wind/power/speed to give the same lift (often not noticeable though), but will be really difficult to stall, even with major rider errors, and will turn much better :rollgrin:

8) Peter

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Re: Stall question for high aspect wing in light wind

Postby BWD » Fri Apr 21, 2017 5:08 pm

...but there is a stall speed also, for given parameters of the wing, shape, loading, etc. despite any user skills.

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Re: Stall question for high aspect wing in light wind

Postby matth » Fri Apr 21, 2017 10:02 pm

OzBungy wrote:
Fri Apr 21, 2017 2:06 pm
matth wrote:
Fri Apr 21, 2017 2:26 am
I don't think you can compare the two. Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle


https://www.youtube.com/watch?v=17JRkEC1Egk


http://amzn.to/2kdfGlL
You had better watch the video and read the book again. I think you missed something.
Did you watch the video?????????????????? start at 45 seconds, it's more about Newtons law FORCE=M x A, for every action there is an equal and opposite reaction , according to video narrator.

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Re: Stall question for high aspect wing in light wind

Postby OzBungy » Sat Apr 22, 2017 2:01 pm

matth wrote:
Fri Apr 21, 2017 2:26 am
.... Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle

...
Like I said. You obviously don't understand the principles ... and you can't spell Bernoulli.

Bernoulli is the cause. The action/reaction generating lift is the effect. It works the same for wing in any fluid, whether it's in water or air.

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Re: Stall question for high aspect wing in light wind

Postby matth » Sat Apr 22, 2017 2:18 pm

OzBungy wrote:
Sat Apr 22, 2017 2:01 pm
matth wrote:
Fri Apr 21, 2017 2:26 am
.... Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle

...
Like I said. You obviously don't understand the principles ... and you can't spell Bernoulli.

Bernoulli is the cause. The action/reaction generating lift is the effect. It works the same for wing in any fluid, whether it's in water or air.

OZBungy it's not my theory nitwit, just passing on a different opinion. You obviously believe you know more than the gentlemen in the video, is he completely wrong? did you listen to his explanation?


More reading if you have the time.

http://www.theinertia.com/surf/foilboar ... they-work/

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Re: Stall question for high aspect wing in light wind

Postby Kamikuza » Sat Apr 22, 2017 2:39 pm

OzBungy wrote:
Fri Apr 21, 2017 2:06 pm
matth wrote:
Fri Apr 21, 2017 2:26 am
I don't think you can compare the two. Hydrofoils do not get lift in the same way as a airfoil(wing) Beroulli's principle


https://www.youtube.com/watch?v=17JRkEC1Egk


http://amzn.to/2kdfGlL
You had better watch the video and read the book again. I think you missed something.
I found a .pdf of that book. Looks like heavy going for a non-specialist :o


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