Who does this for S.U.P.'s? (Video)

[StandUpRyan]

I like this show about surfboards.



And I want to know if anyone makes videos like this for SUPing.

Warning: If you don't like Red Bull (or Billy Mays) you'll hate this.

[SUPCHLU]

You're correct in your warning.

I couldn't take more than about 45 seconds before I started getting coffee jitters through my computer screen and shut it off. 

[raf]

He should try it without the coke. 

[PonoBill]

He's got aspect ration backwards--I got that far and then puked.

[StandUpRyan]

He's got aspect ration backwards--I got that far and then puked.

Can you tell me where he's wrong? I want to understand aspect ratio. He says its a measurement of the width to the length of a surfboard - and a high aspect ratio board is shorter and wider.

Can you tell me how it really works?

[StandUpRyan]

Hey PonoBill it looks like you're wrong and this video is right according to several surfboard shapers.

Rusty: http://www.surfline.com/blogs/talking-design-the-board-blog-with-rusty-preisendorfer/rusty-and-friends-on-the-physics-of-aspect-ratio-in-surfboa_41287/

And Hydrodynamica: http://surfboardsbyhydrodynamica.com/hulls/

But thats just my quick research.

[raf]

aspect ratio = width squared/area (from one of the diagrams in the link you posted), which isn't really the same as width/length.  I believe that factoring in the area rather than the length will take into account the shape of the board; ie fuller nose, pulled in tail, etc.  Personally, I think its is too complexicated for our good. 

[surfinJ]

Another simm inspired board.

[StandUpRyan]

aspect ratio = width squared/area (from one of the diagrams in the link you posted), which isn't really the same as width/length.  I believe that factoring in the area rather than the length will take into account the shape of the board; ie fuller nose, pulled in tail, etc.  Personally, I think its is too complexicated for our good. 

Thanks Raf!

[pdxmike]

You learn something new here everyday.  I'd never seen "aspect ratio" in print--I'd just heard it, and I always thought it was "pecked ratio".  As in, "That racing board has a long-ass pecked ratio" or "That stumpy board has a short-ass pecked ratio". 

[old bosun]

I think PB has it right:
"In aerodynamics, the aspect ratio of a wing is essentially the ratio of its length to its breadth (chord). A high aspect ratio indicates long, narrow wings, whereas a low aspect ratio indicates short, stubby wings.[1]"

[StandUpRyan]

I think PB has it right:
"In aerodynamics, the aspect ratio of a wing is essentially the ratio of its length to its breadth (chord). A high aspect ratio indicates long, narrow wings, whereas a low aspect ratio indicates short, stubby wings.[1]"

Are you taking into account the flow of air or water over a surface?

An airplane wing moves forward with its width pointing in the direction its moving, but a surfboard moves forward with its length pointing in the direction its moving.

So a wing has a high aspect ratio when more width is moving forward. This means a surfboard has high aspect ratio when it has greater width moving forward as well.

Which means a shorter, wider surfboard has a higher aspect ratio than a longer, skinnier surfboard.

This of cours all relates the same to SUP's.

This seems to agree with the video, and with the shapers I've researched in the last couple hours, but still interested for you guys to point out if I'm misled.

[pdxmike]

If there actually is a standard way of looking at aspect ratios for boards (which is debatable) and anyone got it backwards (which is debatable), that says more about how the frenetic narration of the video scrambles viewers' brains than it does about aspect ratios--which I think was the gist of the aspect ratio comment in the first place. 

[raf]

That makes a lot of sense, Standupryan.  I think you are correct.  Glider wings or passenger airplanes have high positive number aspect rations (8s, 10s, 11.5 for example).  Surf boards have numbers in the decimals (.65 for example).  So maybe the better way to understand it is the distance across which the flow travels (squared), divided by the area.  Or crudely simplified: distance across flow surface/distance of flow surface.  thanks for the questions...I'm learning this as I go too.

[lunchbox]

Geez...I should have paid more attention in math class instead of daydreaming about the next south swell