Windsurfing slalom/speed sail twist

Too much downhaul can utterly kill a sails performance and stability. Just as bad as too little.

I am following this topic with great interest and thank you Andrew for raising the question :-).

To me it's totally clear we're already bound by the box that we created the last decennia. Remember, it's only decennia of knowledge from the start of our beloved sport that got us here in the first place.

So why bother looking for the smoking gun within the box, litterally, when in reality the answer lies outside of the box we created ourselves.

The answer is not with the question how much twist is the right amount of twist. The answer is with the question why we need twist in the first place. The answer really is with the lack of power to compensate for the added drag that water brings, in it's non frozen state.

I see ice as a metaphore within our sport and it shows us our mortality as human beings and species. However important we might feel as "leading" organism in the world, we constantly forget to raise the right questions and in this case it's no different.

How can we increase efficiency, realizing the limitations we have as humans: length, weight, power, regardless how large one is as individual rider compared to the norm?

How can we increase efficiency per size? This is what we should look at from all given angles possible, knowing what we know after a few decades of development to unravel the mystery that makes us fly like butterflies over the waters of the seven seas.

Twist only holds so much of the answer. It's the sum of all elements that creates an optimum amount of twist for a given sail. A top rider can feel exactly which amount of twist is needed, which amount of positive or negative outhaul is needed, batten tension etc., in order to squeeze out the last drop of a given rig.

The main question here is: what kind of overall shape do you want a rig to have in order to maximize the power for a given person's weight, size and strength and, equally important, to minimize drag. When thought through in an eloquent way, the answer will automatically come from deeper within: control should be the base layer on which you build that rig as a designer of sails for those with limited strength: windsurfers.

We are the sum of the stays that hold the rig of a sailboat AND we've got something extra. We've got sensors in our body, organic sensors that help us stabilize the platform on which we stand and the rigs that's being connected by a small joint.

For us as windsurfers this is normal. For those who never felt what we are feeling on any day with more than a mild breeze, it's not.

We should take advantage of our biggest weakness: the lack of strength, and turn it into a feat. We could do so through accepting that given fact, embrace it and look for what we're best at: feeling.

We humans feel and can connect in ways no other organic system seems to do. But, just like with this sailing metaphore, we're succeeding to create a big mess out of the opportunities at hand. To me this also comes from the fact that we as humans feel superior to those on which our pleasure is based. The seacreatures where we come from. We are organisms formed by the force that shaped us and forms the largest part in us: water.

Now if we would think cellbioligy instead of physics. How would we then create the best sail possible? Wouldn't we adapt, just like we have done as species? This rethorical question brings me back to the sensors in the here and now: we humans.

We are wired through the WWW. We send and recieve. That's something we forgot but could be more aware of in the now than we have been for centuries. A time in which we forgot about higher values in life. A time in which we thought we were superior to those who said: ich habe es nicht gewusst. And what are we doing? Aren't we the same?

We look away from violence and act as if it's just not there. We live our happy lives and feed on fear, in the most in your face way as one could ever imagine. The news we're watching is showing us how to think and to be fearfull.

I might be crazy but I feel this simply wrong and a simple sport like windsurfing could be an incentive to turn this fear around and help make human life into something beautiful. All human life! So also those who now need to seek for shelter when bombs are hitting their homes because of some morons at the top who feel war is needed to calm the masses down. And we, silly cows, we consume and point fingers at the planes in the air, the boats that are cruizing the waters and ride our cars as if nothing could happen to us. We like pointing fingers and use facebook foor that. That's why I left. That's why I stopped looking at what's actually happening in the world: a totally stupifying, numb making dragon is catching us by our throats and leads us to oblivion as we're not seeing the kid anymore that is now hoping for a bomb to drop on his or her house as this little child doesn't WANT to live anymore.

Windsurfing was the first funsport born out of the hippie era. We evolved from triangle sails into sails with battens and wider heads. We then invented cambers to support the draft and balance. We then moved to easier to hold platforms on which kids could easily get to learn the sport and glide within a few hourse. Trapeze, for the talented to be learned within a week in which a mild breeze hits the shore.

What I hope for, and what I dream off, is that we, through sports and a new to be formed game could help turn the youth of the world around and give them a perspective to live for. Getting together. That's what this all should be about. Getting together by accepting your personal limitations as man and mankind.

Let cell biology be leading. Let organisms be leading and who knows, we might leave our grandchildren a world in which no whale washes ashore anymore with a belly full of plastic.

Lets start cleaning this earth and follow in the steps of Mandela, Ghandi, Matin Luther King, and not to forget: all mothers in the world. It's time for a turn around. It's time for the matriarch to rise and this is what I see in the now. We need to respect the fact that earth is our mother.

In love is the answer and only if we live from love for all living creatures in the world we can expect ourselves to get to the next stage of the computergame our world has become.

Think human: feel, love and then you find the answer. Think machine and you will become a machine that neglect all the facts written above. I truly believe we, as society are using this society as excuse for the missing personal action. We lack the wisdom, courage, determination and care to ensure our grandchildren can live the day. Now what does this say about us. What kind of message do we send to those out there?

We are not alone, even Nasa acknowledges that and expects to find proof of life on another planet within a decade.

The answer on twist? Think the small people we are and think the strength: feeling we hold, and you find the answer to the next generation of sails and who knows, much more.

Chris249 explains pretty well in general forum thread by Nubie "Who invented loose leech sails." Sail twist is needed at differing amounts according to the style of sailing to be done.. A raceboard sail leech differs heavily to a slalom sail. An old 80s 6.5m possibly has same power as a new 8.0m loose leech sail. Its the development of better boards n fins as a complete unit which has made necessary the twist n loose leech sail to be investigated.

With the greatest respect Kwibai, I think you are missing the point.

It is a given that the sailor and whole rig interaction is part of the equation, but what I want to know is the physics a behind it.
Why is it that we have arrived at this point?
Before we know something concrete about that, we are just flailing around in the dark with trial and error.
Now if we could get a grasp on just some of the reasons for why this system works, we may have a more definite direction to go in.

What we see is different. You see that there is something that works and you are happy with that.

I am not happy with all the differing thoeries that may or may not explain it, and have little or no proper evidence to back them up.

I see qustions of WHY it works and WHAT is it about it that works. I know it works - more or less. I what to see some hard science evidence to explain it properly so we can focus on taking it further without lots more of the 'error' part. With trial and error, it is very easy to go down dead ends and waste a lot of energy and time. The history of windsurfing design is littered with it. If we had some evidential scientific explanations, we may be able to find ways to tune the whole rig to suit all size sailors better, and find those directions much faster to make us faster.

What you describe is the way things have been done and evolved, very slowly, because no one REALLY understands the physics and aerodynamics involved. It is that part I am trying to find answers to.

Biological evolution too untold millions of years to tune lifeforms to the environment. I just have not got that much time.

Purely biologically speaking we are all one. We can conclude that we need to find the best synthesis possible between the visible components water, board, fin, sail, rider and then combine them with the non visible components. If you think deep enough you get to the words: air and feeling.

Take a breath first, before you read on (if you haven't fallen asleep). Feeling. The answer is with air and feeling.

Now if we could use the laws of physics to measure the combined forces the elements involved evoke, we might be able to find an answer to the question how much twist is needed but if we forget about cell bioligy, we might forget about that what cannot be seen.

I am sure the fastest responding sail possible, will be fastest for all and that given sail should first of all be incredibly easy to handle.

The better a rig feels the sailor, not the other way around, the faster one could go. So concluding and as a direct answer to your question: twist is related to body tension of the package at hand: the sailbody. The sailbody is related to the mast and cambers holding on to the mast, seen from this equation. The mast is related to the twist.

The sailor holds the rig with his or her fingertips and feels the tiniest change in windstrength at the various sections of the sail through the self balancing rig he or she holds. He is doing so while the seas outside break on a tormented shore which in leeward has a sandy coastline and the perfect speedstrip. It's blowing 35 knots on average. Wind is pretty laminar.

What kind of twist would we need you think?

How fast could we theoretically go you think?

We could go easily, hands down, go faster than 100 kn/h in that given breeze, relatively speaking to the forces on the sail that are being translated to the fingertips of the rider at hand. The rider glides and doesn't have to fight. Please again, try to understand or better feel what I am implying here. Visualize yourself on the speedcourse, every muscle tensed..

There is no answer possible to your question other than that we need a constantly varying amount of twist in a self setting sail that can be held with support of the harness, the righting moment and a few fingertips that steer this rig into the right direction with no problem whatsoever to balance the rig.

That my friend (litterally as eventhough we never met in the flesh I highly value you as a friend), is the right amount of twist. And that my friend is also an answer, but from the complete opposite side of the room.

I would really advice you to sit, relax and watch the movie as that guy ain't dumb. And if you listen carefully, he is also talking about twist. Organic twist. The twist I am trying to explain to you :-). I am windsurfer like you, and translate that what is being said to the thing I love most in my life, next to my beautiful girlfriend: our beloved sport.

In cell biology there are answers to be found, just like there are technical solutions to make these answers, visions of a sail that could be real, come alive. For that you need physics.

Ultimately cell biology is the true gift: inspiration. Inspiration, not from survival, but from the will to evolve to the best possible evolutionary solution. The rest is execution.

So what we saw and see as leading: physics, in the end would also hold back progress if we wouldn't open up to the other side of the equation: organisms and more important, what we are filing under organism.

In this case, in answer to your question, I propose to file the rig, sail, board, fin, waterstate, air and feeling under organism. Only if we do so, we might be able to find the best possible answer on your question.

I am on love for our sport my friend. What the guy in the video is "selling" is more real than most of us realize in the now. Another guy I could advice to you is Rupert Sheldrake. He abstains more from this spiritual metaphores that Bruce Lipton is using and it would be easier for you to hear what he is actually saying after hearing Rupert Sheldrake first. Once you peel off this layers of over enthusiasm or poetic wording that, for Lipton, is needed to explain that what cannot be excplained, and get to the core, there is a lot of sense in what he puts forward.

My point is, that once you shift your focuspoint, solutions are being offered to you from an angle you simply didn't take into account before.

My suggestion is to see wind/air, waterstate, fin, board, sail, rider as one organism, the organism we truly are. If you are thinking about this from a profound level, not shallow as in...I rig my sail, put in my fin and go windsurfing. No, if you are going out and dedicate yourself to get the maximum out of the conditions at hand, you start paying attention to the last drop of detail and you start to become one with your gear.

Isn't that what GPS speedsurfing is all about? Isn't that what makes it so addictive?

So, yes I like to look deeper and wider to us as society and reflect on and come back to a topic if it interests me.

Twist is the most magical word to us as windsurfers since we started out that hunt for speed and just found out longer battens up until the mast, make a sail faster. I was already in it when we started to cut-off old windsurfers and put footstraps on them. Look at where we are now.

I got hooked to speed and never let go, so my drug, the drug I am on is love for our sport. And this love makes me think, feel and act like a hippie, not the drugs the hippies once needed to set themselves free from conventions. I mean, I am not against marihuana but I don't need it or crave for it to be convinced there is more to this life than we can see as humans. I don't smoke, I just don't feel like it, obviously after having a few sips as a young windsurfer and in the now an occasional smoke with an international visitor wanting to "feel" Amsterdam.

I just feel we are slowly missing the point as society and sometimes that makes me sad, hence my remarks on the kids we forget as a reminder of the consequences of our self indulgence as society.

But then I see sparks of hope and this hope, amongst other things is within this World Wide community of speed addicts, who can dig in deep into questions like twist. That is where I started from and that is what got me "on" what you would like to be on as well.

Now the answer is simple...you will want to be on the set I am designing in my head and for which I am trying to find the right talented engineers. We are moving and I am sure we are on the right track, also in regards to twist :-).

One way to find out is to cut it off and see what happens. Got any old, surplus to requirements sails that would otherwise go in the bin?

Great find Andrew!

Well, that is my question as well.

My observation is that even when he is pumping to get out of a gybe, the top of the sail does not actually look like it has air pressure. It is still loose and flapping.

I can think of a few hypothesis that could be explored to answer this question:

1. The top of the sail IS actually doing nothing positive aerodynamically, but this actually leaves the bottom of the sail do everything so lowering the CoE to where it can be made best use of via the limited weight and leverage of the sailor. And it is better to have a long chord working area so they just make the sail bigger so it does not scare customers off, as it would if the top was just cut off. Also, if you just cut the top off you would have to have a different mast that was also cut off.

2. The top of the sail lines up with the airflow and this somehow smooths and reduces the tip drag vortex. Hard to believe this though with the sail flapping around all over the place.

3. The sailor rigged when the wind was lighter and didnt have time to change sails before the race so he just made the top past non effective so he could cope.

any other ideas?

The point is. These are all just totally unsupported hypothesis without any actual data to prove them. As far as I can work out, no one has tested a windsurfing rig in such a way to actually find out and show how the air flows over it? We know that sails like this work well in some situations, but do we really, really know the Physics of why?

Mathew, sails n fins are only trying to mimic what is found in nature. Sail designers mustve looked at a birds wing for inspiration. Twist n looseness of leech is required bcoz we need to control the power produced. The sail is not part of the human body. We cannot control its shape or power as a bird infinately controls its wing in flight. We are stuck with a lifeless man made substitute.
Sure lets do the tests n refine the design. But until we have say, 97 sensors n servos which can infinately change the shape n power at will for performance, we are stuck with what we have. A design which has come a long way in the past 40years. But still has a LONG way to go to be equal with what is found in nature.