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Wing Surface Areas

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Created by Casso A week ago, 8 Aug 2018
Casso
NSW, 3449 posts
8 Aug 2018 11:48AM
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A bit of analysis of front wing surface areas:

Casso
NSW, 3449 posts
8 Aug 2018 11:50AM
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I read somewhere the Go Foil's area is the model size x 10 in cm2 but this seems way too big compared to others that I know are similar sizes.

Does anybody know the real areas of the Go Foil wings?

Piros
QLD, 5159 posts
8 Aug 2018 1:58PM
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That was my thoughts cm2 but it's not , I even asked Dave Kalama it's just a rough figure that's it. The only ones that are dead set accurate is Axis so the Axis 820 is 1443 cm2 and if you want a good comparison it's roughly around the size of the IWA so 1700 is not accurate for it's size so it's more like 1450 not 1700 , clear as mud and I pretty sure the new Naish X/L is also a bit bigger than the IWA and they have that as 1572

colas
2639 posts
8 Aug 2018 1:15PM
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Be wary that you can measure surface in two ways: the projected surface (the surface if the shadow on a flat surface), and the "developed" one, the surface of the upper skin of the wing, following the curves.

The developed one can be useful, as the more curve the more lift, so it is a way to factor in the shape lift, and thus the surface is a more reliable indicator of the lift.

For instance the Gong Allvator L 80cm wingspan has a projected surface of 1675cm2 and 1925cm2 developed, that is 15% more. In size M, 70cm wingspan, it is 1257 / 1450, 15.4%. We do not have the dimensions of the future 90cm and 100cm wings yet.

I guess Casso figures are for the projected surfaces, but it may be worth asking the manufacturers. Maybe some are using the projected surfaces and other the developed ones?

Add to this the fact that I heard that some manufacturers (I think it was Go foil - or was it slingshot? -, but I cannot find the info) use the total surface of both wing + stab to muddy things more...

Casso
NSW, 3449 posts
8 Aug 2018 4:31PM
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colas said..
Add to this the fact that I heard that some manufacturers (I think it was Go foil - or was it slingshot? -, but I cannot find the info) use the total surface of both wing + stab to muddy things more...

Yeah - that's what I thought might be the case for the Go Foils, i.e. total of both wings.

JB
NSW, 1863 posts
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9 Aug 2018 11:03AM
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Piros said..
That was my thoughts cm2 but it's not , I even asked Dave Kalama it's just a rough figure that's it. The only ones that are dead set accurate is Axis so the Axis 820 is 1443 cm2 and if you want a good comparison it's roughly around the size of the IWA so 1700 is not accurate for it's size so it's more like 1450 not 1700 , clear as mud and I pretty sure the new Naish X/L is also a bit bigger than the IWA and they have that as 1572


Here is pics of the Naish XL vs the GoFoil IWA. Naish XL is a little bigger and way sexier .





Ride safe,

JB

JB
NSW, 1863 posts
Site Sponsor
Thursday , 9 Aug 2018 11:38AM
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FYI, some additional information I just obtained from Nil Rosenblad (Naish Foil Engineer and Designer).

All Naish Wing areas are measured in "Projected Area". Whilst actual surface area is useful for calculating parasitic drag and the like, it is projected are that will have the most importance to a rider. Here's a quick diagram for those unsure of what Projected area is.



Also FYI, our rear/stab areas are as follows,
STD - 280cm2.
XL - 375cm2.

So I guess if you're trying to compare to say GF (assuming they use combined wing area). The Naish XL combo is 1947cm2 (Projected Area).

To help with any other calculations, here is the combined projected areas of all 3 Surf Foils and used rear combos.
- Thrust Surf Medium with Std Rear - 1312cm2
- Thrust Surf Large with Std Rear - 1516cm2
- Thrust Surf XL with Std Rear - 1852cm2
- Thrust Surf XL with XL Rear - 1947cm2

I think looking at this, might make sense of the theory of combined wing projected area of GF?

Enjoy the numbers,

Regards,

JB

JB
NSW, 1863 posts
Site Sponsor
Thursday , 9 Aug 2018 11:44AM
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Here's another chart I found,




This is direct off a google search and not my numbers.

JB

JB
NSW, 1863 posts
Site Sponsor
Thursday , 9 Aug 2018 11:54AM
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Ok, so I started really geeking out with Nils and got some more insight into wing area's. And it's pretty interesting.

Ever wondered (really) why there is angled wings. They actually contribute lift to two different planes. In the Rear wing the projected area in the horizontal plane directly correlates to how much PITCH stability (resistance to 'porpoising') is being added. While the projected area in the vertical plane PLUS the area of the 'rudder' (if there is one) directly correlates to to how much YAW stability (directional stability) is being added.

If you get really 3D, you can understand these angles working to produce flight stability on different planes.

Interesting stuff,

Enjoy,

JB

Piros
QLD, 5159 posts
Thursday , 9 Aug 2018 11:57AM
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Thanks JB that's really good stuff

balinnz
1 posts
Thursday , 9 Aug 2018 12:07PM
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Another chart I found, gofoil areas seem a bit more reasonable in this one


Casso
NSW, 3449 posts
Thursday , 9 Aug 2018 7:08PM
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balinnz said..
Another chart I found, gofoil areas seem a bit more reasonable in this one


Yeah - that seems about right for the GFs. Good find.

toppleover
QLD, 1355 posts
Sunday , 12 Aug 2018 3:51PM
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Does anyone have a chart showing diff foils weights & also some foils float - others sink, what are the pros & cons please?

colas
2639 posts
Sunday , 12 Aug 2018 1:55PM
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I put here for reference what I found on the Zone from one of the Ke Nalu foil team member ("LM"):

I'm 99% sure ours are also projected (they were sized by my 3D design guy). I know when we've attempted to look at others it's projected area we were looking at (& what we found with Naish foils is that we agreed with what they reported...not so much with others. Those that do report their sizing anyway) but honestly I have no idea what others are doing when measuring their own & it does make it confusing because everyone sizes seem to be all over the map. I agree with what you mentioned Nils had to say about the comparison between actual & projected. & also the fact that without everyone measuring the same way it does throw a wrench in the works.


It reminds me of the time where some sailboard sail makers were counting the mast sleeve into the surface of the sail, and not others, a 0.5m2 difference, quite huge.

Piros
QLD, 5159 posts
Monday , 13 Aug 2018 10:42AM
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toppleover said..
Does anyone have a chart showing diff foils weights & also some foils float - others sink, what are the pros & cons please?


These are just ones I've tried , no order. Plus don't let a sinking foil put you off , it's makes no difference in flight and sometimes an advantage in choppy conditions. I do personally prefer a light floating foil on my prone but doesn't worry me on my Sup.

GF Floats
Axis Floats
Naish Floats
Carbon Innovation Floats
Signature Floats ( the lightest of all )
SlingShot Sinks
Neil Pryde Sinks
Starboard Sinks
Air Rush Sinks
Lift Sinks (but super light)



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"Wing Surface Areas" started by Casso