| Re: F20 Freestyle
[Re: BLR_0719]
#221400 10/11/10 01:09 AM 10/11/10 01:09 AM |
Joined: Nov 2007 Posts: 271 Atlanta, Ga BLR_0719
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Posts: 271 Atlanta, Ga | It's a copyright problem. I'll PM you how you can watch it. | | | Re: F20 Freestyle
[Re: Lockenfisch]
#221403 10/11/10 01:40 AM 10/11/10 01:40 AM |
Joined: Nov 2007 Posts: 271 Atlanta, Ga BLR_0719
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Posts: 271 Atlanta, Ga | Okay I found the answer. Its a legal dispute between youtube and our organization GEMA that works for artists and their copyrights, earnings when their music is played in public. Blame Google. | | | Re: F20 Freestyle
[Re: BLR_0719]
#221405 10/11/10 02:41 AM 10/11/10 02:41 AM |
Joined: Feb 2009 Posts: 43 where the wind never blows Lockenfisch
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Posts: 43 where the wind never blows | Thank you guys. BLR I can't try your proposal cause I have no account there. Tony your link works fine  Really interesting movie. It looks like when the boat is coming out of the water it loses speed for some reason and falls down, again takes up speed and falls again ... did somebody ever try the F20 with straight boards? Do the curved ones really make a big difference?
Last edited by Lockenfisch; 10/11/10 02:44 AM.
| | | Re: F20 Freestyle
[Re: macca]
#221418 10/11/10 05:55 AM 10/11/10 05:55 AM |
Joined: Sep 2007 Posts: 757 japan erice
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Posts: 757 japan | any ideas of the speeds at that sweet spot?
eric e 1982 nacra 5.2 - 2158 2009 weta tri - 294
| | | Re: F20 Freestyle
[Re: macca]
#221419 10/11/10 06:04 AM 10/11/10 06:04 AM |
Joined: Sep 2005 Posts: 893 waynemarlow
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Posts: 893 | The quickest mode is in the middle part of the video, where we are twin trapezing downwind, the leeward board is up a little bit and the windward board is up a lot more.
Why bother then to put curved boards on then if the quickest part is when the boards are raised somewhat, you would be better off with inclined boards in that case. The A camp has the curved boards in the not sure camp still and many are complaining of the number of broken boards + the time needed to raise one board to get best effect, Me thinks the jury maybe still under deliberation. As to the minscule little bit of " jump " mode followed by immediate slow down of the boat ( induced drag of the foil breaking back into the water is more than if the foil was in the water ), nah find a boat wake and then you would see some real air time . | | | Re: F20 Freestyle
[Re: macca]
#221423 10/11/10 06:51 AM 10/11/10 06:51 AM |
Joined: Sep 2004 Posts: 2,584 +31NL Tony_F18
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Posts: 2,584 +31NL | The quickest mode is in the middle part of the video, where we are twin trapezing downwind, the leeward board is up a little bit and the windward board is up a lot more.
I noticed they where sailing with the windward board fully raised going upwind yesterday as well, even though the wind was quite light. | | | Re: F20 Freestyle
[Re: waynemarlow]
#221424 10/11/10 07:08 AM 10/11/10 07:08 AM |
Joined: Jun 2001 Posts: 1,021 Australia macca OP
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Posts: 1,021 Australia | The quickest mode is in the middle part of the video, where we are twin trapezing downwind, the leeward board is up a little bit and the windward board is up a lot more.
Why bother then to put curved boards on then if the quickest part is when the boards are raised somewhat, you would be better off with inclined boards in that case. The A camp has the curved boards in the not sure camp still and many are complaining of the number of broken boards + the time needed to raise one board to get best effect, Me thinks the jury maybe still under deliberation. As to the minscule little bit of " jump " mode followed by immediate slow down of the boat ( induced drag of the foil breaking back into the water is more than if the foil was in the water ), nah find a boat wake and then you would see some real air time . We raise the boards a little bit depending on the wind strength, we start off with the board down and then once you are trapping fully downwind, then we raise it a little and then we go back down fully in really windy stuff. Also wave state plays a part in the balance too, so its a lot more complex to get the most out of the boat compared to a F18 but the reward is a very quick machine. The reason the A class guys are not fully converted to the curved foils is for a number of factors:- 1. The limited amount of foil curve/length allowed under the rule 2. The A cat is narrow anyhow and the curved foils reduce the righting moment even further 3. The A cat is not adding any sail area downwind and as such the foil effect is not as apparent. We had 2 M20's which were identically rigged and both had interchangeable daggerboard slots, we did many, many hours testing and the result was very clear: The Curved board boat was always quicker. And Inclined boards are not even close to as good as the curved boards in that application. We have some pretty good designers... and from their assessment it wasn't even worth exploring. In the video we are just playing around with the boat, jumping it a bit and having a bit of a laugh. When you have the boat in full speed mode, it looks pretty boring.. just hammering along faster than you think is decent for any sailboat! | | | Re: F20 Freestyle
[Re: erice]
#221428 10/11/10 07:34 AM 10/11/10 07:34 AM |
Joined: Apr 2002 Posts: 602 Wilmington,NC Dlennard
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Posts: 602 Wilmington,NC | any ideas of the speeds at that sweet spot? Mike and I found out that the boat will foil out of the water at 16knts down wind. | | | Re: F20 Freestyle
[Re: Lockenfisch]
#221432 10/11/10 08:04 AM 10/11/10 08:04 AM |
Joined: Jun 2001 Posts: 9,582 North-West Europe Wouter
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Posts: 9,582 North-West Europe | Really interesting movie. It looks like when the boat is coming out of the water it loses speed for some reason and falls down, again takes up speed and falls again
It is an unstable system with a positive feedback loop where the foils eventually stall en the whole thing starts all over again. The same thing was happening with the ORMA tris as far back as 5 years ago. That is why foiling moths have a control rod that adjusts the angel of attack of the foil to smaller values when the boat rises too high. The Nacra Freestyle as no such thing and this is the result. Wouter
Wouter Hijink Formula 16 NED 243 (one-off; homebuild) The Netherlands
| | | Re: F20 Freestyle
[Re: Wouter]
#221433 10/11/10 08:20 AM 10/11/10 08:20 AM |
Joined: Jun 2001 Posts: 12,310 South Carolina Jake
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Posts: 12,310 South Carolina | Really interesting movie. It looks like when the boat is coming out of the water it loses speed for some reason and falls down, again takes up speed and falls again
It is an unstable system with a positive feedback loop where the foils eventually stall en the whole thing starts all over again. The same thing was happening with the ORMA tris as far back as 5 years ago. That is why foiling moths have a control rod that adjusts the angel of attack of the foil to smaller values when the boat rises too high. The Nacra Freestyle as no such thing and this is the result. Wouter It's actually stable when you have your weight placed properly because these are not foils designed to lift the boat clear of the water. As Macca mentioned, in this video they were purposely putting their weight to the rear of the boat to make it leap out of the water when that critical speed (16knots) was obtained.
Jake Kohl | | | Re: F20 Freestyle
[Re: Lockenfisch]
#221438 10/11/10 09:43 AM 10/11/10 09:43 AM | MN3
Unregistered
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Unregistered | it loses speed for some reason and falls down, again takes up speed and falls again ... Have you tried it while wearing a cape? it seemed to work for Jake, but perhaps you need to also carry a plunger at the same time?  | | | Re: F20 Freestyle
[Re: taipanfc]
#221472 10/11/10 08:04 PM 10/11/10 08:04 PM |
Joined: Jun 2001 Posts: 12,310 South Carolina Jake
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Posts: 12,310 South Carolina | Must be a way to control the height rather than crudely pulling boards up and down. As Wouter said above, the moths have this semi-automated with the wand allowing you to control your height. The manual part is setting what level of ride height you want, and you regularly change this based on your speed and wave/wind conditions. Moving weight back/forward was what the mothies did initially when foiling started, but now don't move at all as the systems work.
And this new 20 better be quicker than the old 20! In 15 knots of breeze and flat water on the weekend, it didn't stand a chance against the moth downhill. Motored past it when they thought they were doing full noise... It's definitely faster than the N20 and by a fairly substantial margin.
Jake Kohl | | |
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