A bit of theory
From SecondSailing
Like with most things, a bit of understanding of things going on is helpful with sailing in SL.
So let's peek behind the curtains.
Of course, a lot of things here discus real world concepts but it's the model all boats in SL follow closely. So discussing them as if things are really this way in SL helps understanding.
How a sailing boat works
If you ask people, most will answer you "A sailing boat works, because it is pushed around by the wind". This is as true as it is wrong.
Just drifting in the wind, going in the direction the wind pushes us is surely the oldest and most simplest form or sailing. But these ancient times when this was the only form of sailing have long gone. Todays boats allow to follow the course, we want (well, sometimes at least).
The following graphic shows three possible situations you might find on the water.
Like in most diagrams in sailing, the wind, indicated by the arrows, blows from the upper edge of the image.
In the first situation, the wind comes from behind, blows into the sail. This is the situation already discussed. The boat simply is pushed by the wind. This is called going "down wind".
The second situation shows a boat with the wind coming from the side. The third shows a boat with the wind coming from ahead. Modern boats can sail in this situation and the sail works in a different way (more to the theory goes --> here), nevertheless the boat can sail forward in this direction.
Let's take a closer look. The first boat has an angle indicated, called α. This angle is called the sheet angle. You might note, that in all situations the angle is so that the wind hits the inside of the sail.
This is important and true for all situations. If the wind hits the sail from the outside it can't sail. Being hit inside is mandatory but not the only criterion for good sailing. As a rule of thumb one can say, that, the more the wind comes from behind, the larger should the sheet angle be. Some good values to remember are:
| wind angle | sheet angle |
|---|---|
| 40° | 20° |
| 90° | 45° |
| 180° | 90° |
For the beginning sailing with these three values is sufficient. It is also sufficient to use these numbers roughly, say use a sheet angle of 25° for all wind angles between 40° and 70°. The more you learn and get experienced the better you will be able to control the sheet angle.
The forbidden area
A sailing boat sails, when the wind is blowing inside the sail. If the angle between the wind and the sail gets so small, the boat won't sail anymore. On the other hand the sail must have a certain angle to the centerline of the boat to sail. The more you sail upwind, the smaller get both angles until they get to small to sail. For this reason, there is an area upwind, that you can't sail into. This is the forbidden area. There are ways to get around the deficit. We will get to that later.
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