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Old 7th May 2009, 04:52 PM   #1
iago
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Default volume/knots/sail ... or width/knots/sail

with the new boards have the sense to speak of liters required for planar or would be better to speak a minimum width?
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Old 7th May 2009, 07:12 PM   #2
Roger
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Hi iago,
For early planing (in the < 10 knot range) width is usually more important than volume (as long as there's enough volume).
A narrow board (<70 cm) with 140-160 liters of volume will not plane nearly as early as a board with a similar volume but 80-100.5 cm wide.
At one point, we actually had "virtual volume" ratings, but that did not reflect the true volume of the board and was confusing to many sailors.
So we have the true "tank test" volume of both wide and narrower boards, but there is no "test" for how early each will plane.
Part of the puzzle here is that wider boards use longer span fins, and in general, much larger sails.
Formula boards are pretty much the acknowledged "earliest to plane" (the Apollo may be slightly better) and they have around 140-160 liters of true volume but are 100.5cm wide.
The Formula Windsurfing class rules stipulate the 100.5 cm width, and 70 cm max. fin depth with a 12.5 m2 max. sail size.
So, for earliest planing, you need a wider board, with a huge fin, and a huge rig.
Once you get above around 15 knots, then width becomes more a liability than an asset as wider boards (without the huge fin and rig of a formula board) do not handle the chop so well and once you get to 20 knots, narrower is often better as it gives you more control.
Hope this helps,
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Old 7th May 2009, 08:43 PM   #3
iago
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follow your reasoning,
if I quietly planing with futura 122lt (width 71.5) 6.4 sail with 10/12 knots,
with futura 111lt (68 width) and 7.2 sail. ( always with 10/12 knot)
I can get the same result?
Sorry for my English very elementary
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Old 8th May 2009, 07:59 AM   #4
Roger
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Hi iago,
If you are currently planing with a Futura 122 and a 6.4 m2 sail how are you measuring the windspeed, and what is your weight.
Planing on a 6.5 m2 rig, in 10-12 knots is quite a feat.
You either must be very light weight, or the wind is really a bit more than 12 knots.
If you were currently planing with a 7.4 m2 in 12 knots, then yes, increasing the sail size between 0.5 and 1.0 m2 might allow you to plane in the same conditions with a Futura 111.
Figuring out what board and sail combination will plane in what windspeed with what sailor weight is not so easy.
Sailor skills, wind quality, fresh vs salt water, the type of sail are some of the other variables that make it difficult to predict what will plane in what windspeed with what size rig.
Hope this helps,
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Old 8th May 2009, 04:40 PM   #5
iago
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in my usual spot, we have a fixed anemometer at a height of 5 meters .
when I see that there are 12 knots i can always leave a planar, clearly depends on the constancy and the gusts of wind. to start in planing using the technique of pumping. Use futura122 with fin "liquid pro maui 42cm" and a sail" Neil Pryde 6.4 excess "
my weight is really 65 kg.
I expect to use in the future:

futura 111 and sail Point7 model "square" 7,2 mq.
What do you think?

Last edited by iago; 8th May 2009 at 04:47 PM.
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Old 10th May 2009, 01:36 PM   #6
PG
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At your weight (65) kg and a 6.4 sail I do think that the F122 is an oversized board, especially if you are skilled enough to pump well. I believe that you should plan as early with the F111, with the same sail, and somewhat earlier with a sail almost a square bigger.

I would say: go for the switch. You will have more fun!
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