Polar Diagrams are a graphical representation of the speed through water at various wind angles. They are very handy for planning your route as they will tell you (under ideal conditions) what speed you will make at varying wind angles. This will allow you to choose a route that is best suited to your yacht.
Polar chart of Wisdom. A full keel, cutter rigged, heavy displacement boat.
Now, a sloop with a very high-aspect ratio rig and keel will perform very well to windward. This will let you sail to a windward destination with ease and efficiency. In our case, the above polar diagram well demonstrates our performance statistics.
As you can see, we do not sail well to windward, but we do sail quickly on a beam reach and down wind, but when we turn the wind forward of our beam, we instantly slow to a crawl.
After enough data collection, I was able to compile our own polar chart that will now help us choose a better weather route to our next destination.
An important thing to note on a polar diagram, you will see that you will be able to point to windward, but you won't sail very fast. This means that you will not cover as many miles and you will get stuck somewhere as the weather changes over you. If you could choose a course that will have you sail faster, you will minimize the time of the voyage and allow you to get there in a quicker fashion. A quicker voyage means that the weather forecast won't expire before you get to your destination.
