Aft aka airfoils on Sodebo

Lykke

Member
87
21
So Cal
Does anyone know the logic behind these? When you stuff your bows your AWA shifts way aft, so it would seem that they are more, not less, likely to make you pitch pole. 

[My wife’s breasts are way too nice for this here snake-pit of wisdom, besides I’ve been here for over a decade, until I forgot my password and my email address from way back is long gone]
 

3E15C197-433F-4A47-9E23-8E6004E4AA90.jpeg

1BD94900-24D9-4FB2-8187-A8FB80C5455A.jpeg

 

3to1

Super Anarchist
I'll bet they're far less worried about what happens when the AWA goes aft than they are about keeping the stern down in the first place at speed. the thing is flying, those are essentially elevators, they also reduce drag.

 
Last edited by a moderator:

Airwick

Member
491
229
Victoria, BC
Pretty sure the main function is just to reduce drag on the aft face of rear beam. it doesn't looks like they are shaped to generate any lift one way or the other.
They would be a "liability" when stuffing the bows going downwind for sure...

 

vokstar

Member
242
128
Tasmania
To reduce drag for the most part, it's becoming a bigger deal in foiling boats. Gitana did an interesting vid on it. There is a series of vids discussing other aspects of foiling boats, they are really rather interesting indeed. 




 

Sidecar

…………………………
3,132
1,497
Tasmania
I'll bet they're far less worried about what happens when the AWA goes aft than they are about keeping the stern down in the first place at speed. the thing is flying, those are essentially elevators, they also reduce drag.
^^^^^ This. And don’t be surprised if the leeward one can be angled down to produce upward lift, whilst the windward one is angled up for downward lift. In either position, they both help with drag.

 
Last edited by a moderator:

Zonker

Super Anarchist
9,716
5,673
Canada
Beam bat wings!

If you want an efficient BEAM you don't make it the shape of a wing. You make a rectangular box section. Material in the shape of a wing isn't a weight efficient beam.

It's a drag reduction device primarily. 

 

Rasputin22

Rasputin22
13,911
3,470
Beam bat wings!

If you want an efficient BEAM you don't make it the shape of a wing. You make a rectangular box section. Material in the shape of a wing isn't a weight efficient beam.

It's a drag reduction device primarily. 
Happy now?

7xlK8.jpg


 

karst

New member
37
39
Bat wings have been used for quite a while. The DOG Cup (Dogzilla v A5) saw use by both teams. 
 

image.jpeg

 

3to1

Super Anarchist
^ that event was a freak show and an absurd pissing contest, but the the oracle tri was and always will be one of the straight-up illest boats ever to touch water. beat that cat like a red headed step child.

 
Last edited by a moderator:

jmh2002

Member
68
66
To reduce drag for the most part, it's becoming a bigger deal in foiling boats. Gitana did an interesting vid on it. There is a series of vids discussing other aspects of foiling boats, they are really rather interesting indeed. 
This, but these sections are also actually creating lift too. The recent Gitana video is good, and I'll post an older one below too (their whole channel is has interesting technical insights, so I'll also add the recent cavitation video too).

There is an old Sail-World article that covered it very well, and here is the most relevant paragraph https://www.sail-world.com/news/222146/?source=rss

"This new form not only reduces the drag, by pulling the flow of air tightly around it, but it also creates lift, which will have the effect of making the platform more lightweight. This fairing was made of Oratex and it's a flexible canvas akin to what you find on glider wings or microlights. This represents an additional surface area of around 32m2 and weighs in at nearly 50kg. In optimum conditions, studies predict a gain of over 1 knot at 30 knots of boat speed."

yysw266201.jpg





 
Last edited by a moderator:




Top