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 Post subject: Roll Jibe
PostPosted: Sat Mar 21, 2009 2:58 pm 
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Location: Thunder Bay,On
Nice medium air roll jibe,drop tiller and steer with cross bar
Image
Both crew and skipper stay on the windward side
Image
Boat pivots with front of hull lifted
Image
As boom crosses over skipper goes to other side
Image


Last edited by mmadge on Sun Mar 22, 2009 7:43 am, edited 1 time in total.

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 Post subject:
PostPosted: Sat Mar 21, 2009 11:30 pm 
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Just curious - why would you do this on a cat?

The physics on a mono-hull make sense and we roll tack and gybe everything up to TP52. I have been thinking about this quite bit tonight and from the photos dont see an advantage.

Are you turning the boat with the new leeward hull with less tiller movement? It did not look like you pumped the boat out of the gybe as the leech of the main looks slack.

Not being critical - just tying to understand.


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 Post subject:
PostPosted: Sun Mar 22, 2009 5:44 am 
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I don't think it's a "roll jibe" per se. They're jibing around the weather mark - the crew is not in the same position as when you're jibing from broad reach to broad reach.

This is not something I would want to do (especially on a 16) in any kind of breeze. You'll end up with the boat on top of you.


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 Post subject:
PostPosted: Sun Mar 22, 2009 7:56 am 
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MBounds wrote:
I don't think it's a "roll jibe" per se. They're jibing around the weather mark - the crew is not in the same position as when you're jibing from broad reach to broad reach.

This is not something I would want to do (especially on a 16) in any kind of breeze. You'll end up with the boat on top of you.
Yes you are probably right Matt.For sure they are gybing around the weather mark,these series of pictures is of Cam Owen(third at the worlds) and Sue Ferris (Singapore National Sailing coach).They are executing a gybe almost exactly like what you do on a laser and I know the dynamics of the boat are different,but it does look some what impressive.When I talked with one of of the guys I know from Aust. he says they are always experimenting with ways of making the 16 sail faster around the course.
Actually a lot of things that we do to sail the boat around the course fast involve sailing on the edge,i.e roll tacking,sitting as far forward as possible downwind..


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 Post subject:
PostPosted: Mon Mar 23, 2009 8:59 pm 
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It looks like they are jibing around the leeward mark. The skipper and crew start the turn with weight well back and stay there to get the bows up for the turn. It almost looks like the team doesn't move because the front boat is about to be run over and keeping the boat turning to avoid collision is currenlty more important than keeping speed. See how close the boats apear in the first photo and how the first boat is pulling away with the crew better positioned in the last photo? The boats may look closer in the first photo than they really are. Telephoto lens' do this, but it does look close.


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 Post subject: Gybing the H16
PostPosted: Tue Mar 24, 2009 11:21 am 
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Location: SE PA/ Chesapeak Bay
Guys,

Gybing the H16 is different from Gybing other boats, especially other boats w/ dagger or centerboards.

A boat w/ a center or daggerboards "Pivots" about the location of the boards. The H16 w/o any center or daggerboards has a tendency to pivot on its rudders .... so to make the H16 gybe the fastest you move aft to raise the bows and reduce the waterline length ... put the helm over to just short of "stalling the rudders" and carve the turn. The lighter the air/wind the more/longer you want to stay on the origonal "upwind" side and "roll tack" the boat. Now you want to roll tack the boat so that the boat assumes the proper "angle of heel" and re-attaches the airflow over the sail and starts generating lift/power and off you go on your new tack. As you finish you gybe you must "flatten" the boat out fore and aft with-out shaking the boat to much ... position the "movable ballast, ie the crew wieght properly for the conditions.

Now you gybe a H18 slightly different .... as the daggerboards are not in the center lengthwise on the H18, you move the crew wieght to a position that raises the bows slightly effectively placing the daggerboard in the center of the actual waterline length ...... smoothly put the helm over again just short of stalling and carve the turn ..... staying on the origonal windward side to help "pull" the boat over on the new tack and assume the proper "angle of heel" ... let the boat start to accelerate and gently reposition the crew wieght trying hard not to violently shake the boat.

From the series of pics the team/crew on the H16 behind did an excellent Gybe!!! Though their crew wieght could have been slightly more aft ... but there is a balance of enough room for the helm position to "work in" and standing the H16 up on its sterns to pivot

I do the same when Gybing with the tiller stick and Rudder crossbar as in the pics on my H18

So .... a H16 you tend to "slam" around more on a Gybe vs w/ a center/daggerboard boat where you want to "carve" the turn. Also the H18 is a much heavier boat and you want to conserve the momentum of the boat as it takes slightly longer to accelerate.

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 Post subject:
PostPosted: Tue Mar 24, 2009 11:33 am 
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You know looking at the third pic again I noticed that the crew is all the way aft to the crossbar ... that is a very very good gybe .....

But I would suggest to both teams that they need a float on the end of their tiller sticks so the sticks do not sink and are thereby harder to retrieve. If the stick is floating on top it is easier to pick-up .... but that is only a small detail ....

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 Post subject:
PostPosted: Tue Mar 24, 2009 3:01 pm 
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Harry I totally agree, this is a text book gybe at the weather mark.BTW Cam(skipper in the pics) uses a carbon tiller so it probably floats.


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 Post subject: Great Gybe
PostPosted: Tue Mar 24, 2009 3:40 pm 
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Location: SE PA/ Chesapeak Bay
The tiller sticks maybe "Carbon" and in the first two pics Cam's Tiller stick is bouncing on top of the water's surface ..... but by the last pic it appears that Cam's tiller stick is angled at maybe 45* downwards and is no longer on top of the water's surface.


As that tiller stick is smaller in diameter then a "Hot Stick" it will not hold as much water internally and may not be too heavy. Idea: fill the end w/ spray foam to keep the water out????

A "Hot Stick" full of water is heavy!!! .... and once I actual somehow had the tiller stick sink and during the gybe it got caught under the hull , in front of the rudder!!! Definately NOT fast sailing!!!! and a "Pain" to lift the rudder and retrieve the tiller stick. So instead of exiting the mark and concentrating on boatspeed and tactics ..... I'm screwing around facing the wrong way at the back of the boat. Definately NOT a "textbook" rounding!!!!!

First thing on a new "HotStick" .... a "corkball" float!!!!

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H-18 mag/ #9458
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 Post subject:
PostPosted: Tue Mar 24, 2009 6:56 pm 
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Location: Clinton Lake Kansas
Harry,

It's either carbon or a newer Hobie USA issue. Standard white stick is now covered with black shrink tube and the end has a cap or a grip.

Nobody races with an adjustable on the 16 (well almost nobody).

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