Sailing UPWIND.

Up wind sailing.

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It is the first thing you learn in windsurfing and the hardest thing to do on a short board.

The question is always “full planning or slow down and work up wind?”

So lets have a look at going upwind not planning first.

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The longer the waterline length not planning, the faster the board will go. 1.a) sailing with the front up, b. creating as much length as possible. Once the board starts moving, the rocker line will be trying to lift the front up when kept flat.

2.) You also need to create as much sideways resistance as possible, so angle the board, weighting the windward rail. This will also make the nose go down easier. You have to find a happy medium but on a sinker you can even have the front slightly underwater.

Obviously the more board in the water (waterline length), the position of the central lateral resistance will change. You can see in 3.) and 4.) the rig position is very different just to keep the board going straight.

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The closer to the wind you try to sail, the more sideways pressure you will get as the sail becomes nearly parallel to the board. As in 1.)

So again you have to find a compromise and sail at a slightly lower angle as in 2.) keeping the sail more open. The faster you go the more apparent wind you will have, you must find the optimum speed. When you go above that optimum speed you just open the sail and spill wind.

When can you plane upwind?

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A windsurf board starts to plane when the board speed is around 10 knots, so in this graphic I have placed the wind speed at 10 knots. Very marginal planning conditions, it can be done on large boards with big fins and sails. Most short board sailors have a minimum of 12/15 knots

Sector A.) shows that there is no problem going up wind planning when you are going at a speed up to wind speed.

1.) is not planning, so you can point at 45 degrees to the wind.

2.) Your optimum sail angle is about 20 degrees to the wind. So yes you can still go upwind with enough sideways resistance from the board and fin.

Sector B.) is where you have to choose speed or point upwind. In 3.) you can see that if you travel at 15 knots, you are only just going up wind.

Sector C.) Unless you have very specialised material you will not go upwind but be enjoying the speed, reaching in and out.

Most people sailing are traveling at around 18/20 knots so when the wind is 20+ knots they are in sector A.

When planning, the board is at it’s fastest when it is flat. When you have large enough fins to create lateral resistance, you turn the  board to your upwind course and just let it ride.

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However when you are using wave or freestyle boards, the fins are small.

The classic way to go upwind is to depress the windward rail as in Y.) This works in slow planning speed but it also keeps the board going slow. You keep as much of the board in the water as possible.

When a fin is angled it creates lift on one side. Here you can see that the lift and sideways force are in the same direction, so less efficient. The board tends to track sideways.

When you can get the board going fast enough, you can encourage the windward rail to lift slightly, as in X.) This is done by a slight pressure sideways with the back foot (not down). Once the rail lifts you release the sideways pressure and let the board ride. It is the rig that is creating pressure against the lift from the fin. Yes the pressure from the rig is going through your legs but it is not a forced pressure. So when you can not find pressure in your rig (underpowered) this technique does not work.

From the front foot strap back the rails on a board are sharp. In X.3) you can see that it is in the water so creating additional resistance, especially on freestyle boards.

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As the boards get shorter and shorter we can have flatter and flatter rockers under the foot straps. A.) is a fast wave board/freestyle board, B.) is a more traditional wave rocker.

1.) this is the board planning at slow speed. You can see that B.) is pushing more water, so slower.

2.) as the board increases speed it will ride onto the rocker further back. A.) the angle of the board does not change so much, the board just lifts out of the water. B.) the front is rising as the board goes back on the rocker.

3.) With correct body and rig positioning A.) is in fact riding more on air, with only the tail and fin in the water. B.) is riding very nose high on the tail rocker so you tend to try to get it down. Sailing on a more forward rocker, pushing water. Hence a wave board is slower.

So on wave boards you do tend to use more the windward rail down to go upwind. When the rocker is flat enough you will be going upwind with the windward rail high.

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The more upright the rig can be the more power you can generate from the rig. Mast foot positioning and sail type will determine the angle the rig will be at.

On wave boards as in 1.) the central lateral resistance tends to be nearer the front footstep, where on flatter rocker boards (freestyle, free-ride and slalom boards)it is half way between the foot straps as in 2.)

You will see that the closer the mast foot is to the front foot strap the more upright the rig will be. a.) is a 5 batten sail, b.) is a 4 batten sail where the centre of effort tends to be further back.

Going upwind is all about choosing the correct speed, when you go to fast you will not be able to point very high. 45 degrees down wind is the fastest point of sailing.

So whether generating full speed for jumps, freestyle or just blasting, you do need to go upwind to have fun. And don’t forget to do down the line wave riding you will need to go upwind very well.

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