High speeds in winds <= 14 kts - Page 3

Roger · 15th December 2008, 11:48 PM

Carlos,
Let us know how it works, please?
I always wonder if the advice I'm giving actually works for
the sailors who are asking.
R

andretsin · 16th December 2008, 01:54 AM

Roger,
I thought more about this question. Well, first of all i wanted to tell you that when i said that i think is the wind which is lifting the board i was meaning the action of the wind directly on the board, not to the rig.
Anyway as you said, this science is very complicated (that is why i love it), and I think there are two different situations.
One of them is the one we are speaking about here. Is in low winds, and is the fin which is giving the lift when rolling quite enough the board. (Much more clear in centerboard boards!)
The other situation is the one i was reffering to. When you sail in high winds >13knots, mainly across the wind or a little bit downwind, at full speed, if you roll just a little bit the board to leeward, the board is behaving like a wing and is lifted by itself. Then you reduce wetted surface to half or even less and you are almost flying. And this i can feel it much more in raceboards because the size of the "wing" (board) is much bigger in comparison to my weight.

Roger · 17th December 2008, 09:51 AM

Hi Andretsin,
As discussed, without alot of science based "testing" I'm not sure it's possible to answer
this question.
I do know that since boards got alot wider and fins alot deeper the whole dynamic seems to have changed and as you suggest, it could be some sort of "surface effect".
If you've ever sailed a Hypersonic, on really flat water with > 15 knots of windspeed, I'm reasonably sure some sort of "surface effect" is taking place.
With flatter bottomed formula and slalom boards it's not so clear, but again as you suggest, rolling the board so that you reduce the wetted surface by almost 50% has to
reduce the drag significantly.
Hope this helps,

michelb · 17th December 2008, 06:41 PM

There is a Link to Carbonsugar.com that shows in the article a very nice photo about flying the fin.

http://www.carbonsugar.com/technique...it-go/#more-27

All need to read this article it shows very clear how to do it.

I learn from there.

Michel

carlosgp5 · 19th December 2008, 04:40 AM

Quote:

Originally Posted by Roger

Carlos,
Let us know how it works, please?
I always wonder if the advice I'm giving actually works for
the sailors who are asking.
R

Hi Roger and everybody,
just came from sea, it was very gusty around 16k, and I had in my mind:
I tried to pull the frontstrap while pushing the backstrap sort of sideways...
I got better angles upwind, but when the gusts arrived, I had to really sit on the harness, so kinda leaving some weight down on the board... And then after the gust I would start again pulling the front and pushing the back sideways, kinda canting to leward...
Am I on the right way? at least close?
Tks

Roger · 19th December 2008, 05:16 AM

Hi Carlosgp5,
Soundws like you are getting very close.
I do not understand why when a gust comes along and you "sit down" you increase the
weight on the board.
Seems to me that you would "sit down" to increase your weight on the rig when the power is coming up.
Also, are you lifting and pulling with your front foot, or only pulling?
When you get it right, your hips will kinda "lock" into a position that's quite uncomfortable
thr first few times you get it, but soon it will feel completely natural and become "how I go upwind fast at the best angle".
Is your rear heel over the edge of the board so you are actually pusing sideways (downwind) on the rail of your board?
Hope this helps,

marek · 19th December 2008, 03:54 PM

carlosgp5 · 19th December 2008, 04:46 PM

Hi,
Well, I sit on the harness when get the gust because of the extra power, otherwise would lose trim and open the sail... isn´t it right?
If I´m actually pulling and lifting I´m not sure, but I have that in my mind and I´m trying to do so. You´ve got it perfectly, I really felt my hips. I´m also using the heel on the edge of the board... let´s see how does it go on the weekend.. my forecasts are NE15k 1m of swell- Formula classic conditiions down here.
By the way... aren´t these guys on the photo going downwind?
Thanks for helping

Ken · 19th December 2008, 10:26 PM

Roger,

I know you know this, but Carlos "sitting down", as you said, "increases weight on the rig", which is the only way to keep a formula board from taking off. Sheeting out on a formula board takes the downward force of the rig off the board, which can result in "flight", especially if the windward rail is lifted while "riding the fin" in a gust of wind.

I learned early that if you get overpowered on a formula board, you must keep the power on, sit in the harness to increase weight and downward force on the board. Just the opposite of what I had been used to on other boards.

Ken

Roger · 20th December 2008, 08:51 PM

OK Ken and Carlos,
I'll defer to Ken's greater experience on modern formula boards and larger sails here.
I may even be "sitting down" a bit myself, but just not realizing it.
Unfortunately, I haven't raced formula or FE boards in several years, so my technique
would be a bit outdated and "rusty" for sure.
R

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

15th December 2008, 11:48 PM	#21
Roger Dream Team - School Guru Join Date: Aug 2006 Posts: 2,060	Carlos, Let us know how it works, please? I always wonder if the advice I'm giving actually works for the sailors who are asking. R

16th December 2008, 01:54 AM	#22
andretsin Member Join Date: Oct 2008 Location: Spain Posts: 28	Roger, I thought more about this question. Well, first of all i wanted to tell you that when i said that i think is the wind which is lifting the board i was meaning the action of the wind directly on the board, not to the rig. Anyway as you said, this science is very complicated (that is why i love it), and I think there are two different situations. One of them is the one we are speaking about here. Is in low winds, and is the fin which is giving the lift when rolling quite enough the board. (Much more clear in centerboard boards!) The other situation is the one i was reffering to. When you sail in high winds >13knots, mainly across the wind or a little bit downwind, at full speed, if you roll just a little bit the board to leeward, the board is behaving like a wing and is lifted by itself. Then you reduce wetted surface to half or even less and you are almost flying. And this i can feel it much more in raceboards because the size of the "wing" (board) is much bigger in comparison to my weight.

17th December 2008, 09:51 AM	#23
Roger Dream Team - School Guru Join Date: Aug 2006 Posts: 2,060	Hi Andretsin, As discussed, without alot of science based "testing" I'm not sure it's possible to answer this question. I do know that since boards got alot wider and fins alot deeper the whole dynamic seems to have changed and as you suggest, it could be some sort of "surface effect". If you've ever sailed a Hypersonic, on really flat water with > 15 knots of windspeed, I'm reasonably sure some sort of "surface effect" is taking place. With flatter bottomed formula and slalom boards it's not so clear, but again as you suggest, rolling the board so that you reduce the wetted surface by almost 50% has to reduce the drag significantly. Hope this helps,

17th December 2008, 06:41 PM	#24
michelb Member Join Date: Jun 2008 Location: Chile, Santiago Posts: 92	There is a Link to Carbonsugar.com that shows in the article a very nice photo about flying the fin. http://www.carbonsugar.com/technique...it-go/#more-27 All need to read this article it shows very clear how to do it. I learn from there. Michel

19th December 2008, 05:16 AM	#26
Roger Dream Team - School Guru Join Date: Aug 2006 Posts: 2,060	Hi Carlosgp5, Soundws like you are getting very close. I do not understand why when a gust comes along and you "sit down" you increase the weight on the board. Seems to me that you would "sit down" to increase your weight on the rig when the power is coming up. Also, are you lifting and pulling with your front foot, or only pulling? When you get it right, your hips will kinda "lock" into a position that's quite uncomfortable thr first few times you get it, but soon it will feel completely natural and become "how I go upwind fast at the best angle". Is your rear heel over the edge of the board so you are actually pusing sideways (downwind) on the rail of your board? Hope this helps,

19th December 2008, 03:54 PM	#27
marek Member Join Date: Aug 2007 Posts: 95

19th December 2008, 04:46 PM	#28
carlosgp5 Member Join Date: Dec 2008 Location: SC Posts: 61	Hi, Well, I sit on the harness when get the gust because of the extra power, otherwise would lose trim and open the sail... isn´t it right? If I´m actually pulling and lifting I´m not sure, but I have that in my mind and I´m trying to do so. You´ve got it perfectly, I really felt my hips. I´m also using the heel on the edge of the board... let´s see how does it go on the weekend.. my forecasts are NE15k 1m of swell- Formula classic conditiions down here. By the way... aren´t these guys on the photo going downwind? Thanks for helping

19th December 2008, 10:26 PM	#29
Ken Member Join Date: Aug 2006 Location: Dallas, Texas USA Posts: 797	Roger, I know you know this, but Carlos "sitting down", as you said, "increases weight on the rig", which is the only way to keep a formula board from taking off. Sheeting out on a formula board takes the downward force of the rig off the board, which can result in "flight", especially if the windward rail is lifted while "riding the fin" in a gust of wind. I learned early that if you get overpowered on a formula board, you must keep the power on, sit in the harness to increase weight and downward force on the board. Just the opposite of what I had been used to on other boards. Ken

20th December 2008, 08:51 PM	#30
Roger Dream Team - School Guru Join Date: Aug 2006 Posts: 2,060	OK Ken and Carlos, I'll defer to Ken's greater experience on modern formula boards and larger sails here. I may even be "sitting down" a bit myself, but just not realizing it. Unfortunately, I haven't raced formula or FE boards in several years, so my technique would be a bit outdated and "rusty" for sure. R