Upwind Kinetics:
by Steve Cockerill, Rooster Sailing

Currently the most contentious aspect of Olympic sailing is rule 42 - the one that polices anything that comes outside propelling the boat other than by the action of the wind and the waves. This difficult subject is revisited in the months leading up to the Olympics in a vain hopeto see what it is the sailors are developing this time. When you look at rule 42 it allows for movement to adjust the trim of the boat, but not to energise the boat though waves. When I discussed this article with a top judge, he was able to say that he interpreted body movement inwaves as legal or illegal by imagining how those movements would effect the position of a chair on a polished floor. If the chair were to move across a room then the action would be illegal, but that other movements that merely changed the angle of the chair could be acceptable,except of course where the action of the sailor caused the leach to flick. He also stated that this was only his interpretation and that by no means would this be acceptable to all judges. Despite this, his words made great sense to me and took a cloud of misunderstanding away. It isvery hard to remain within the rule and to police the rule if you do not understand what it means.
My perspective is that the action of an Olympic sailor in a boat on the sea is a fantastic sight and makes our sport look worthy of its Olympic status. However, I am unsure how this relates to the sailor who will find it difficult to compete on the sea with someone who has perfectedkinetic body movements for sea sailing. I guess that in all true sports there comes a point where we are not trying to make my Father compete on equal terms with Linford Cristy. Perhaps sea sailing makes demands on us that are more in the extreme so that the younger ones might have aphysical edge.
Despite this debate - one of the most commonly asked questions from aspiring sailors, young and old is how do you sail through waves upwind? Which way do I steer and which way should I move my body? The easy answer is to try to trim the boat with body weight and rudder so that the bowof the boat makes the least up and down movements though the waves, i.e. to reduce the pitching and slapping. If there were some way we could pre-jump the bumps on the race course (much like a downhill skier) then we could at least keep the big leaps into the air followed by a bigdive into the next wave down to a minimum. Smooth is fast as they say. Olympic sailors are becoming fitter and stronger and are not using their bodies not to propel the boat, but to reduce the effects of the action of the waves on the speed of the boat though the water.
This explanation is not easy - as it involves an investigation of hiking style, which links to trim with an analysis of the rudder and how it acts as a lifter or sinker of the bow - all this before we look at the kinetic movements within the boat. So find a nice quiet place to take itall in and read on. Watch out Lindford Cristy!

Hiking style
It might be worth a little read of my article on hiking style but in brief it discussed the advantage ofstraight leg hiking from the perspective of knee damage and hiking stamina. It argues that straight leg hiking reduces the load on the knee and that pointed toe hiking helped keep the knee straight. What it did not say is that it also increases the grip of the sailor on the deck ofthe boat. Because it gives a large contact area with the side of the boat, leading to good transmission of kinetics to the hull. That said - there is another - perhaps more important aspect that straight leg hiking improves - TRIM.

When bent leg hiking - sailors have a tendency to have to keep the boat heeled to stop their bum from hitting the water. This is done by bearing away in the lulls - when perhaps keeping the boat on the straight course might be more effective. In the gusts the boat has massive weatherhelm and the effort required to keep the boat from luffing is basically effort trying to stop the boat with the rudder. The more the heel - the more the boat naturally wants to luff through the natural shape of the hull. So bum down is slow and harder work.
Rudder analysis
In the downwind article called the 4th dimension I introduced the effect of rudder as a way to control the roll of the boat (the rudder as a life saver). In that account we could also add that in using the rudder to steer the way the boat wants to go flattens the boat, sinks the transom andlifts the bow.
Every pull of the rudder when heeled slows the boat down and lifts the transom out of the water, burying the bow and making the boat heel even more - see the diagram.

This does not include the added wind pressure in the sail that comes from bearing away in the gusts.
Every push of the rudder will lift the bow/sink the transom and drive the back of the boat flat, relieving the pressure of the weather helm and reducing the conflict of the forces = speed and height. Obviously the hiking style becomes important again as if the sailor is drooped overthe side, he will hit the water far too soon and reduce the tendency to want to push the rudder at all.
One important thing to take from this explanation is the effect of the rudder when heeled on the weight of the bow, pushing the rudder makes it lighter and pulling makes it heavier. Too droopy a bum and the push becomes unusable as the sailor hits the water.



Kinetics - The simple 'purist' approach - passive movement -

the sailor tries to reduce the pitching moment of the bow by moving his/her weight back and forwards over the waves to remove their own weight from the pitching weight of the boat. See diagram
The more active approach is that the sailor uses his/her weight to push the bow of the boat down or lift it up. In this case it is the stopping of the forward movement that throws the boat down and the stopping of the movement back that lifts the bow up. I tend to demonstrate thispoint by sitting on a chair, and instead of leaning side to side, (left and right) leaving the legs of the chair on the floor, the stopping of the left lean should lift the right legs and the stopping of the right lean should lift the left legs of the chair. Considerable strength andcontrol is required though the core of the backbone and pelvis. A popular new phrase now used by physiotherapists is 'core stability'. This is the jargon for backbone and pelvis lower support, a bit like lowers on a 4000 rig. The tighter they are the more the mast (backbone) staysupright and in column. It also allows the backbone to move better around its centre of gravity or in a sailing analogy - it allows us to sail the boat with slacker shrouds and let the rig do more work for us.
Moving away from analogies, again the hiking style makes a big difference to the amount of bow lifting or sinking possible. If the toe straps are loose, then I find that when I am trying to transmit to movement to the boat my legs only float around the cockpit rather than transmit themovements to the boat.
Now the kinetic movement still follows the same as the passive movement but the action is sharper and has a small time advance that allows the reaction to have some effect. When the boat has reached the top of the wave, the body should have already reacted against the bow of the boatto allow the bow to start to cut the top of the wave off and start the bow down the back of the wave. This stops the bow from launching itself into the air and piling into the next wave. Then as the boat approaches the next wave, the backwards movement has already began with the sharpstop to try and lift the bow just before piling into the next wave. Thus the dynamic movement has effectively made the ends of the boat lighter and allowed the boat to sail though the waves with less pitching and slapping.
Its not all over yet!
Rest Point Summary -
We have now the active movements sorted for the bow lifting and sinking in waves. We have a good hiking style which gives us the maximum grip on the side of the boat to transmit all these movements efficiently.
Now lets consider steering and the effects that it has on the boat. When heeled slightly we discussed earlier that the rudder is also a lifter and sinker of the back of the boat. Remember that when bearing away, the transom is lifted out and the bow is buried. When pinching up to thewind, the opposite happens - the bow becomes lighter and the transom sinks. Wow! Perhaps we can combine the two -the body movements in sympathy with the steering. The bow is then lifted by the action of the stopped back movement ' and by the use of pushing the rudder.
Perhaps we can even consider helping the rudder further with the help of another kinetic movement, so that the rudder then has more of a following action for the turn, but remains effective in the lifting and sinking areas - so less slowing effect.
With kinetic twisting body movement we can help the boat want to turn to the wind and turn away from the wind. Imagine sitting on a chair again. Instead of twisting from side to side - try twisting with attitude and start to make the chair legs move from around from side to side. Inthe same way - the movement has got to finish as you want the effect to take place. So back in your boat, the upper body can be used to generate a turning kinetic which is trying pull the bow to the wind - up the wave and turn it away from the wind when you bear away.
So combining the forwards and backwards techniques with the steering and the turning - you now have the complete answer to sailing through waves. See the complete video - sorry but it is slightly overdone to make it very clear - a little bit too much lee wobble for legality at theend.

Related products developed by Rooster Sailing to aid the top class Laser Racer -

Rooster Hiking Shorts - maximum comfort and stickability with batterns to aid hiking - arriving in April.

Rooster Hike Boot -proved to be the best at the Youth Words!

Rooster Padded Toestrap - helps thepointed toe hiker

Rooster Carbon Tiller Extension - transmits thepull and push with solid feel
( available for Topper, Laser, RS200, RS300, Enterprise, 49er, - in fact everyclass!!)

Laser Carbon Tiller - simply the strongest and very, very low!



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