Forums > Windsurfing General

LIght winds boards quandary

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Created by Francone > 9 months ago, 30 Dec 2017
Francone
WA, 299 posts
30 Dec 2017 10:35AM
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I'm looking for a good light wind board myself to improve, if possible. on the performance of my Windsup , wich I find a bit slow in subplaning..
I am puzzled, because just about every board on the market today is spinned as an excellent light wind performer.. ( by light winds I mean sometimes as low as 10-12, peaking not unfrequently to about 15 knts.) Please note that I am after a bit more subplaning speed, not necessarily planing. So may be a larger sail on my Windsup a 9.0 m2 instead of my current 8.0 would do.. I weigh 85 kg

Here is a list of these purportedly "excellent" light winds boards :JP SLW , SB Go, SB US, Fanatic Falcon 159 lt, RRD X-Fire L.W. Exocet 205 RS8., to name just a few..

They all have one thing in common : short and wide, the opposite of traditional longboards, which even seasoned windsurfers today deem unsurpassed (and for one good reason to me)in light winds : their narrower width drastically reduces the drag while their length ensures better gliding.

How can these 250 cm long (or less !!) , 80 cm ++ wide boards be just as good in light winds as the long and narrow traditional longboards ( or their modern counterparts, like the Kona..) at the other end of the spectrum ? It baffles me..

It is a bit, on the obverse side, as though manufacturers cried wolf too much..In the end these seemingly conflicting claims make one skeptic ...

May be the secret of extra-wide, extra short boards is just a piece of colossal circular thinking applied to design : they perform very well( no doubt about it!) because their exceptional width makes it possible to rig gigantic 12 m2 sails to overcome the.. drag.
But then they wouldn't perhaps require such huge ( and costly) sails if they were much narrower and longer in the first place .
Possibly they would perform just as well if not better. ...But it is difficult to dispell the hype...Without it, we wouldn't probably have $ 3000 boards which benefit only the manufacturers and we would have cheaper boards performing just as well

Unless there are other elements in a board's design that weigh more, much more than sheer length and width on the light wind performance.Volume? Rail thickness? Rocker? Board's weight?

May be there is something I'am missing that only a designer can explain

Thanks

Francone

TDG1959
VIC, 27 posts
30 Dec 2017 1:42PM
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Have a look at the WindTeck site on seabreez, the owner/designer sails out of Pelican point and would be quite happy to talk to you.

boardsurfr
WA, 2454 posts
30 Dec 2017 11:59AM
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Check Jim Drake's paper on "Sailboard Hull Forces". Here's the relevant section:


For simplicity, assume that lw = b in the second formula. Then, the formulas simply state that a very wide board will have twice as much hydrodynamic lift relative to width (b) than a long and narrow board. Since the width is also larger, the actual gain in lift you get by going from a 60 cm wide board to a 100 cm wide board would be almost 5-fold.

That's a bit of an oversimplification already, but let's rephrase what this means in non-mathematical terms. The board moving through the water pushes water down and to the sides. The downward push in turn moves the board up, and helps to get on a plane. The outward push is just wasted energy. The ratio of (desirable) downward push and (wasteful) sideways push is about 2x better for the very wide board. That's one reason why very wide boards plane earlier. This part applies even when using the same size sail, for example a 9.5 m sail on a classic race board or on a new "super light wind" board.

Of course, a wider board also allows you to use a longer fin, which in turn allows you to use a larger sail. A formula board can carry a 14 square meter sail, but 12 m is the practical limit. Even that is something most windsurfer's don't want to touch. The advantage of a 12 m sail and formula board over a 9.5 m sail on a full race board in 10-12 knots, peaking to 15, is rather minimal. The workout effect, however, is pretty dramatic. I'm basing that on the last time I raced, where we had a mix of longboards and formula sailors on the water, in exactly these wind conditions.

The next issue that comes into play is hull speed. Shortening the board length from 12 to 8 feet reduces the maximum non-planing speed from 8.5 to 5 knots (check boardsurfr.blogspot.com/2015/08/maximum-speed.html). That means short and wide boards have a larger "planing hump" than longboard, which requires either a lot more power, or a lot more pumping, to start planing.

All the short wide boards you mention will not give you more sub planing speeds - quite the opposite. Their claim to fame is that they will plane is less wind than narrower boards. However, this requires technique and/or larger sails and/or "active sailing" (good pumping).

Your board has a decent sub-planing speed that is higher than the sub-planing speed of any short and wide board. It is, however, somewhat lower than the speed of a narrower longboard, especially a full race board. But the big problem is that it's not designed for planing in flat water. Full race boards like the Starboard Phantom 377 or old Fanatic Cats are designed for planing, so they behave very different in 10-15 knots if you know how to sail them well. Unlike the BIC, they will keep accelerating when the wind picks up from 10 to 15 knots. But for "full fun" on these boards, you need to be able to use the daggerboard to rail them up in marginal conditions.

The Kona One is somewhere in between the BIC and the race boards. You won't get the same speed and the "full fun", but it can plane (although you'll probably need more than 15 knots). It does not rail up as nicely as race boards since it has soft rails and a less powerful daggerboard. On the plus side, it's easier to sail than an old race board since it's wider, and it more robust and a lot cheaper than a Phantom 377. Would it make you happy? That's questionable, since you might regard the performance as too similar to the Bic, especially in 10-12 knots. But I'm very much looking forward to some Kona One racing at the US Nationals in April.

BSN101
WA, 2374 posts
30 Dec 2017 12:54PM
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I love my Mistral EQ2 8.2&8.7 sails but also really enjoy my UltraSonic 147lx95wide with same sails. The US is best planing while the qe2 goes well either way. I won't go larger than KAR8.7 or out in les than 10knots, family life kicks is then or gardening.

If if you get down Sth you can have a go on either. There is an RRD LW on gumtree now in Perth. Or find those boards in Perth to test.

Try them and report back.

Swindy
WA, 456 posts
30 Dec 2017 1:06PM
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All the above boards you mention are designed to be sailed planing in light winds and would be no faster than your windsup in non planing conditions and probably less fun for you. You use big sails and big fins on them and in light airs still have to pump like hell to get them on the plane. Once on the plane they generally keep planing unless the wind dies but do keep going through the lulls. This is what the people that buy them want and they work well for the purpose they are designed for. Also if the wind dies they are big enough to float you home. Its obvious to me this isn't for you so just get an old long board and have fun. It will be an improvement on your windsup.
There are now three choices for light winds. Long boards, big wide boards and foiling. No conspiracy, the choice is all yours.
Hope this finally answers your question.

NCUSAGUY
65 posts
30 Dec 2017 10:02PM
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As stated above, but in simpler terms:

Short wide boards are designed for planing and are dogs as slogging.

For them to plane early, good pumping technique (3-4 pumps) is essential.

Large sails (9-10m) help with the early planing, but only just a little and for most recreational sailors, it's not worth the cost.

If you are stuck with winds around the 10 knot range most of the time, a longboard with good glide is the answer (a windsup is fine, but will become boring quickly). Unless you want to work on good light wind freestyle moves.

Francone
WA, 299 posts
31 Dec 2017 4:55AM
Thumbs Up

Select to expand quote
boardsurfr said..
Check Jim Drake's paper on "Sailboard Hull Forces". Here's the relevant section:


For simplicity, assume that lw = b in the second formula. Then, the formulas simply state that a very wide board will have twice as much hydrodynamic lift relative to width (b) than a long and narrow board. Since the width is also larger, the actual gain in lift you get by going from a 60 cm wide board to a 100 cm wide board would be almost 5-fold.

That's a bit of an oversimplification already, but let's rephrase what this means in non-mathematical terms. The board moving through the water pushes water down and to the sides. The downward push in turn moves the board up, and helps to get on a plane. The outward push is just wasted energy. The ratio of (desirable) downward push and (wasteful) sideways push is about 2x better for the very wide board. That's one reason why very wide boards plane earlier. This part applies even when using the same size sail, for example a 9.5 m sail on a classic race board or on a new "super light wind" board.

Of course, a wider board also allows you to use a longer fin, which in turn allows you to use a larger sail. A formula board can carry a 14 square meter sail, but 12 m is the practical limit. Even that is something most windsurfer's don't want to touch. The advantage of a 12 m sail and formula board over a 9.5 m sail on a full race board in 10-12 knots, peaking to 15, is rather minimal. The workout effect, however, is pretty dramatic. I'm basing that on the last time I raced, where we had a mix of longboards and formula sailors on the water, in exactly these wind conditions.

The next issue that comes into play is hull speed. Shortening the board length from 12 to 8 feet reduces the maximum non-planing speed from 8.5 to 5 knots (check boardsurfr.blogspot.com/2015/08/maximum-speed.html). That means short and wide boards have a larger "planing hump" than longboard, which requires either a lot more power, or a lot more pumping, to start planing.

All the short wide boards you mention will not give you more sub planing speeds - quite the opposite. Their claim to fame is that they will plane is less wind than narrower boards. However, this requires technique and/or larger sails and/or "active sailing" (good pumping).

Your board has a decent sub-planing speed that is higher than the sub-planing speed of any short and wide board. It is, however, somewhat lower than the speed of a narrower longboard, especially a full race board. But the big problem is that it's not designed for planing in flat water. Full race boards like the Starboard Phantom 377 or old Fanatic Cats are designed for planing, so they behave very different in 10-15 knots if you know how to sail them well. Unlike the BIC, they will keep accelerating when the wind picks up from 10 to 15 knots. But for "full fun" on these boards, you need to be able to use the daggerboard to rail them up in marginal conditions.

The Kona One is somewhere in between the BIC and the race boards. You won't get the same speed and the "full fun", but it can plane (although you'll probably need more than 15 knots). It does not rail up as nicely as race boards since it has soft rails and a less powerful daggerboard. On the plus side, it's easier to sail than an old race board since it's wider, and it more robust and a lot cheaper than a Phantom 377. Would it make you happy? That's questionable, since you might regard the performance as too similar to the Bic, especially in 10-12 knots. But I'm very much looking forward to some Kona One racing at the US Nationals in April.


Thanks boardsurfr for your clarity.

Your explanation that the width of the board ( contrary to what I thought) helps planing makes full sense and goes a long way towards explaining my quandary. I

In fact , it is based on something as elementary as Newton's 3rd law. I should have picked it up !

At first, if the 3rd Newton's law factor was the only parameter affecting planing ability, I could not understand why much narrower boards like a Mistral Equipe or even Konas , are viewed as excellent light winds performers, which, I assume, also means planing ability.

The inverse correlation you pointed out between width and maximum hull sub-planing speed has helped me to understand why.

In fact, it may be the equalizing factor between , on one hand, short and wide boards and , on the other hand, longboards in terms of planing ability.
In fact both have at the onset a handicap for planing: a large board because it reduces the maximum subplaning hull speed , a narrow board because the hull has less surface on the water, hence less lift..

These handicaps are overcome , as I see it, by the increased maximum hull speed inherent to the narrower boards and an.. increased muscle effort ( pumping_) as well as by larger sails. in the wide boards .

In the end, can a longboard equal a Formula board in terms of planing ability by changing other parameters in the formula?
Or will a Mistral or any other similar longboard be doomed to a poorer planing performance than short and wide boards? Can this be evinced from the formulas?

You can give me, if you want, a short non-mathematical answer, but it would help me to at least understand their inner, formal logic of your formulas, by understanding the symbols and the concepts behind them, even though my knowledge of maths doesn't go beyond college algebra, .50 years ago .

1.What is the definition of linear component ? Whatever it is, is it the symbol LL ( the left side of the equations)
2. What is q and ? ( alpha)?

Your explanations make my choice much clearer. Others have perhaps told me the same thing, but it is important for me to know the " whys" of things..

All in all, I'll probably stick to my Windsup, hoping that perhaps a larger sail ( a 9.0/9.5 will bring it closer to its maximum subplaning hull speed. By the way, I tried to look at Jim Drake's paper. Unfortunately it was published on the Windsurfing Magazine which has ceased publication. T

Thanks for your help

Francone

boardsurfr
WA, 2454 posts
31 Dec 2017 8:34AM
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Select to expand quote
Francone said..
... The inverse correlation you pointed out between width and maximum hull sub-planing speed has helped me to understand why.



Either you mistyped, or you got something wrong. In first approximation, board width has no relation to maximum hull speed. Maximum hull speed is primarily determined by board length (or, to be exact, the length of the waterline). Wide, early planing boards just happen to also be shorter. It's their shorter length that reduces the maximum hull speed compared to longboards.

The primary relevance of board width to speed in displacement mode (< 10 knots) is drag: wider = more drag. So while the Bic SUP has roughly the same maximum hull speed as a longboard, you'll need more power (a larger sail) to reach maximum hull speed.

But there are two additional very important factors:
1. What was the board design optimized for? Raceboards are optimized for speed at all points of sailing. The Bic SUP is optimized for ease of use in a variety conditions, durability, and low price. Therefore, race boards will be faster.

2. A good longboard can be a ton of fun in semi-planing conditions. Note the "semi" - something between pure displacement and planing. The wide boards made for light-wind planing do not have a semi-planing mode. They are strictly dual beasts: fun when planing, no fun when not planing.

I think semi-planing on a longboard in 10-15 knots is just as much fun as planing on a shortboard in 15-18 knots. If the wind is up and down, e.g. with lulls below 8 knots and gusts to 20, a Fanatic Ultra Cat, F2 Lightning, or Mistral Equipe will be the most fun you can have, unless you are really, really good at sailing huge gear underpowered and overpowered. If you're not, you'll be fighting to stay on a plane in the lulls, and fighting for control in the gusts with your 10.5 or 12.0 m sail.

A large part of the fun in these conditions comes from planing on the daggerboard and the leeward rail. For that to work in 12 knots, you need a large and good daggerboard (e.g. a carbon race daggerboard in a Fanatic Ultra Cat), and sharp rails. Your Bic SUP has neither.

Two other aspects of light wind fun on a longboard is the effortless glide through the water in displacement mode when the wind is very light, and the ability to plane fully in gusts. Again, your Bic SUP limits your fun here. In light wind, it does not quite have the great glide of a narrow board. In gusts, it does not quite jump on a plane, since it has too much rocker and rounded rails.

Your two options are to either (a) get a large sail and early planing wide board, and learn to pump, or (b) get a narrower longboard like a Fanatic Ultra Cat, and learn how to sail that well. Getting a larger sail for your Bic SUP won't do much to ease your current frustration, except perhaps every now and then on a windier day. This is pretty much what tons of people have said in answer to your various posts on various windsurf forums. If you don't want to go either way, get a foil, start working on light wind freestyle, or learn to kite.

Mark _australia
WA, 23452 posts
31 Dec 2017 8:40AM
Thumbs Up

Francone

still wanna be assured you are talking knots, not mph?
Hope you are not frustrated at not planing in 12-15mph and others are talking about planing in 12-15kn?
If thats the case it would be an easy solution.

If its not the case - very good advice above and like Swindy says hopefully it finally puts the matter to bed.... just figure out what genre you want to fit in, and do it

olskool
QLD, 2459 posts
31 Dec 2017 10:46AM
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Longboard /RB makes for easy gliding, easy to plane , go where you like. Formula from what i gather may plane earlier n stay planing longer. But is a lot harder work to get it there. Guess it comes down to whether you like to 'work hard' while sailing or is it all about enjoyment? For me there is no other than Raceboard. Whatever happened to the 80s 'FUNBOARDS'? Seems they were deleted to be replaced by the 'poorer cousin' SUP? ( no centreboard) for upwind ability.

azymuth
WA, 2154 posts
31 Dec 2017 10:26AM
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FWIW - my preference for max fun in 12-15 knots of the boards I've owned;

1) Naish foil / Isonic 121

2) Formula Starboard 186

3) Longboard F2 Lightning WC

4) Slalom Mistral 137

Foil beats the other 3 hands down

Francone
WA, 299 posts
31 Dec 2017 11:52PM
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Select to expand quote
Mark _australia said..
Francone

still wanna be assured you are talking knots, not mph?
Hope you are not frustrated at not planing in 12-15mph and others are talking about planing in 12-15kn?
If thats the case it would be an easy solution.

If its not the case - very good advice above and like Swindy says hopefully it finally puts the matter to bed.... just figure out what genre you want to fit in, and do it


Thanks

I'm talking knts/hr

Francone

Francone
WA, 299 posts
1 Jan 2018 2:57AM
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Select to expand quote
boardsurfr said..

Francone said..
... The inverse correlation you pointed out between width and maximum hull sub-planing speed has helped me to understand why.




Either you mistyped, or you got something wrong. In first approximation, board width has no relation to maximum hull speed. Maximum hull speed is primarily determined by board length (or, to be exact, the length of the waterline). Wide, early planing boards just happen to also be shorter. It's their shorter length that reduces the maximum hull speed compared to longboards.

The primary relevance of board width to speed in displacement mode (< 10 knots) is drag: wider = more drag. So while the Bic SUP has roughly the same maximum hull speed as a longboard, you'll need more power (a larger sail) to reach maximum hull speed.

But there are two additional very important factors:
1. What was the board design optimized for? Raceboards are optimized for speed at all points of sailing. The Bic SUP is optimized for ease of use in a variety conditions, durability, and low price. Therefore, race boards will be faster.

2. A good longboard can be a ton of fun in semi-planing conditions. Note the "semi" - something between pure displacement and planing. The wide boards made for light-wind planing do not have a semi-planing mode. They are strictly dual beasts: fun when planing, no fun when not planing.

I think semi-planing on a longboard in 10-15 knots is just as much fun as planing on a shortboard in 15-18 knots. If the wind is up and down, e.g. with lulls below 8 knots and gusts to 20, a Fanatic Ultra Cat, F2 Lightning, or Mistral Equipe will be the most fun you can have, unless you are really, really good at sailing huge gear underpowered and overpowered. If you're not, you'll be fighting to stay on a plane in the lulls, and fighting for control in the gusts with your 10.5 or 12.0 m sail.

A large part of the fun in these conditions comes from planing on the daggerboard and the leeward rail. For that to work in 12 knots, you need a large and good daggerboard (e.g. a carbon race daggerboard in a Fanatic Ultra Cat), and sharp rails. Your Bic SUP has neither.

Two other aspects of light wind fun on a longboard is the effortless glide through the water in displacement mode when the wind is very light, and the ability to plane fully in gusts. Again, your Bic SUP limits your fun here. In light wind, it does not quite have the great glide of a narrow board. In gusts, it does not quite jump on a plane, since it has too much rocker and rounded rails.

Your two options are to either (a) get a large sail and early planing wide board, and learn to pump, or (b) get a narrower longboard like a Fanatic Ultra Cat, and learn how to sail that well. Getting a larger sail for your Bic SUP won't do much to ease your current frustration, except perhaps every now and then on a windier day. This is pretty much what tons of people have said in answer to your various posts on various windsurf forums. If you don't want to go either way, get a foil, start working on light wind freestyle, or learn to kite.


Sorry, I meant length all along.
The gist of this discussion is based on the lower ( light) winds range of 10-12 knts/hr .

Indeed, it prevails about 45% of the time here and it is a critical range for planing, especially for my Windsup or any other shortboard that is not short and wide...

About 40% of the time, however, we are at about 15 knts/hr, still light winds area, but approaching the planing watershed for my board ( or at least allowing the Bic to approach its maximum non-planing hull speed, which would already be a welcome accomplishment,,).

My Windsup may therefore still be a good, although far from the best, solution.

I do agree that either a longboard or a short-and-wide board would be the best in these light winds ( 10-15 knts).
I could buy a 2nd hand Mistral Equipe I for a more than reasonable price, but I have already tried one and, at 65 cm wide, I found it awfully tippy, perhaps because I was spoiled by the Windsup.

I could probably get used to it, but summers are very short here and planing winds are not prevailing .I wouldn't want to spend most of my time ..swimming around the board while learning. how to keep balance on a toothpick..
It is a question of choosing the "lesser of two " evils" or, more positively, the better of two less than optimal solutions.

Somebody may frown upon the " tipping" factor as a valid criterion, or even consider it non-sensical, but we can't get away from our preferences , often based on objective factors, like our body make-up, our physical shape and our age.

I'll mull it over. I've plenty of time, until next summer!

Thanks for your input, as usual

Francone

NCUSAGUY
65 posts
1 Jan 2018 11:07PM
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Learning on a wide board and then moving to an old longboard - yes, they will seem very tippy. But anyone can overcome that with several hours of practice, then you can appreciate the "glide" and performance of those old race boards. I had/still have my first race board, a 1985 Mistral Superlight, then I moved to an F2 Lightning, then a Mistral Equipe 11 XR. The Equipe was exceptionally fast for a longboard and could blow by most intermediate short board sailors.

BSN101
WA, 2374 posts
2 Jan 2018 5:03PM
Thumbs Up

Select to expand quote
Francone said..

boardsurfr said..


Francone said..
... The inverse correlation you pointed out between width and maximum hull sub-planing speed has helped me to understand why.





Either you mistyped, or you got something wrong. In first approximation, board width has no relation to maximum hull speed. Maximum hull speed is primarily determined by board length (or, to be exact, the length of the waterline). Wide, early planing boards just happen to also be shorter. It's their shorter length that reduces the maximum hull speed compared to longboards.

The primary relevance of board width to speed in displacement mode (< 10 knots) is drag: wider = more drag. So while the Bic SUP has roughly the same maximum hull speed as a longboard, you'll need more power (a larger sail) to reach maximum hull speed.

But there are two additional very important factors:
1. What was the board design optimized for? Raceboards are optimized for speed at all points of sailing. The Bic SUP is optimized for ease of use in a variety conditions, durability, and low price. Therefore, race boards will be faster.

2. A good longboard can be a ton of fun in semi-planing conditions. Note the "semi" - something between pure displacement and planing. The wide boards made for light-wind planing do not have a semi-planing mode. They are strictly dual beasts: fun when planing, no fun when not planing.

I think semi-planing on a longboard in 10-15 knots is just as much fun as planing on a shortboard in 15-18 knots. If the wind is up and down, e.g. with lulls below 8 knots and gusts to 20, a Fanatic Ultra Cat, F2 Lightning, or Mistral Equipe will be the most fun you can have, unless you are really, really good at sailing huge gear underpowered and overpowered. If you're not, you'll be fighting to stay on a plane in the lulls, and fighting for control in the gusts with your 10.5 or 12.0 m sail.

A large part of the fun in these conditions comes from planing on the daggerboard and the leeward rail. For that to work in 12 knots, you need a large and good daggerboard (e.g. a carbon race daggerboard in a Fanatic Ultra Cat), and sharp rails. Your Bic SUP has neither.

Two other aspects of light wind fun on a longboard is the effortless glide through the water in displacement mode when the wind is very light, and the ability to plane fully in gusts. Again, your Bic SUP limits your fun here. In light wind, it does not quite have the great glide of a narrow board. In gusts, it does not quite jump on a plane, since it has too much rocker and rounded rails.

Your two options are to either (a) get a large sail and early planing wide board, and learn to pump, or (b) get a narrower longboard like a Fanatic Ultra Cat, and learn how to sail that well. Getting a larger sail for your Bic SUP won't do much to ease your current frustration, except perhaps every now and then on a windier day. This is pretty much what tons of people have said in answer to your various posts on various windsurf forums. If you don't want to go either way, get a foil, start working on light wind freestyle, or learn to kite.



Sorry, I meant length all along.
The gist of this discussion is based on the lower ( light) winds range of 10-12 knts/hr .

Indeed, it prevails about 45% of the time here and it is a critical range for planing, especially for my Windsup or any other shortboard that is not short and wide...

About 40% of the time, however, we are at about 15 knts/hr, still light winds area, but approaching the planing watershed for my board ( or at least allowing the Bic to approach its maximum non-planing hull speed, which would already be a welcome accomplishment,,).

My Windsup may therefore still be a good, although far from the best, solution.

I do agree that either a longboard or a short-and-wide board would be the best in these light winds ( 10-15 knts).
I could buy a 2nd hand Mistral Equipe I for a more than reasonable price, but I have already tried one and, at 65 cm wide, I found it awfully tippy, perhaps because I was spoiled by the Windsup.

I could probably get used to it, but summers are very short here and planing winds are not prevailing .I wouldn't want to spend most of my time ..swimming around the board while learning. how to keep balance on a toothpick..
It is a question of choosing the "lesser of two " evils" or, more positively, the better of two less than optimal solutions.

Somebody may frown upon the " tipping" factor as a valid criterion, or even consider it non-sensical, but we can't get away from our preferences , often based on objective factors, like our body make-up, our physical shape and our age.

I'll mull it over. I've plenty of time, until next summer!

Thanks for your input, as usual

Francone


Francone, where do you sail?

Francone
WA, 299 posts
3 Jan 2018 12:09AM
Thumbs Up

Select to expand quote
BSN101 said..

Francone said..


boardsurfr said..



Francone said..
... The inverse correlation you pointed out between width and maximum hull sub-planing speed has helped me to understand why.






Either you mistyped, or you got something wrong. In first approximation, board width has no relation to maximum hull speed. Maximum hull speed is primarily determined by board length (or, to be exact, the length of the waterline). Wide, early planing boards just happen to also be shorter. It's their shorter length that reduces the maximum hull speed compared to longboards.

The primary relevance of board width to speed in displacement mode (< 10 knots) is drag: wider = more drag. So while the Bic SUP has roughly the same maximum hull speed as a longboard, you'll need more power (a larger sail) to reach maximum hull speed.

But there are two additional very important factors:
1. What was the board design optimized for? Raceboards are optimized for speed at all points of sailing. The Bic SUP is optimized for ease of use in a variety conditions, durability, and low price. Therefore, race boards will be faster.

2. A good longboard can be a ton of fun in semi-planing conditions. Note the "semi" - something between pure displacement and planing. The wide boards made for light-wind planing do not have a semi-planing mode. They are strictly dual beasts: fun when planing, no fun when not planing.

I think semi-planing on a longboard in 10-15 knots is just as much fun as planing on a shortboard in 15-18 knots. If the wind is up and down, e.g. with lulls below 8 knots and gusts to 20, a Fanatic Ultra Cat, F2 Lightning, or Mistral Equipe will be the most fun you can have, unless you are really, really good at sailing huge gear underpowered and overpowered. If you're not, you'll be fighting to stay on a plane in the lulls, and fighting for control in the gusts with your 10.5 or 12.0 m sail.

A large part of the fun in these conditions comes from planing on the daggerboard and the leeward rail. For that to work in 12 knots, you need a large and good daggerboard (e.g. a carbon race daggerboard in a Fanatic Ultra Cat), and sharp rails. Your Bic SUP has neither.

Two other aspects of light wind fun on a longboard is the effortless glide through the water in displacement mode when the wind is very light, and the ability to plane fully in gusts. Again, your Bic SUP limits your fun here. In light wind, it does not quite have the great glide of a narrow board. In gusts, it does not quite jump on a plane, since it has too much rocker and rounded rails.

Your two options are to either (a) get a large sail and early planing wide board, and learn to pump, or (b) get a narrower longboard like a Fanatic Ultra Cat, and learn how to sail that well. Getting a larger sail for your Bic SUP won't do much to ease your current frustration, except perhaps every now and then on a windier day. This is pretty much what tons of people have said in answer to your various posts on various windsurf forums. If you don't want to go either way, get a foil, start working on light wind freestyle, or learn to kite.




Sorry, I meant length all along.
The gist of this discussion is based on the lower ( light) winds range of 10-12 knts/hr .

Indeed, it prevails about 45% of the time here and it is a critical range for planing, especially for my Windsup or any other shortboard that is not short and wide...

About 40% of the time, however, we are at about 15 knts/hr, still light winds area, but approaching the planing watershed for my board ( or at least allowing the Bic to approach its maximum non-planing hull speed, which would already be a welcome accomplishment,,).

My Windsup may therefore still be a good, although far from the best, solution.

I do agree that either a longboard or a short-and-wide board would be the best in these light winds ( 10-15 knts).
I could buy a 2nd hand Mistral Equipe I for a more than reasonable price, but I have already tried one and, at 65 cm wide, I found it awfully tippy, perhaps because I was spoiled by the Windsup.

I could probably get used to it, but summers are very short here and planing winds are not prevailing .I wouldn't want to spend most of my time ..swimming around the board while learning. how to keep balance on a toothpick..
It is a question of choosing the "lesser of two " evils" or, more positively, the better of two less than optimal solutions.

Somebody may frown upon the " tipping" factor as a valid criterion, or even consider it non-sensical, but we can't get away from our preferences , often based on objective factors, like our body make-up, our physical shape and our age.

I'll mull it over. I've plenty of time, until next summer!

Thanks for your input, as usual

Francone



Francone, where do you sail?


I sail in Canada, on a large lake( when it is not frozen., ...like now at -26 C?) . The water is mostly flat or with a minimum chop. .

Francone

joe windsurf
1482 posts
3 Jan 2018 2:02AM
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this is what we are doing in our neck of the woods





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"LIght winds boards quandary" started by Francone