Imagine you see a boat for sale - you think to yourself, 'I would love to sail the seas in my very own yacht'. But how do you even begin to sail? What is it about the wind that moves a boat? Can you only travel in the direction the wind is blowing?
The first thing to get to grips with is how a sail actually works. I remember as a young child wondering what the point of a sail was. I couldn't understand how a big sheet being blown around by the wind could be an effective method of propulsion. There is of course, a lot more to a sail than simply 'catching' air and moving a craft along. While the sailor is essentially at the mercy of the elements, harnessing the power of the wind is only possible with the right knowledge.
So how does it work? Interestingly, a sail works in a very similar way to the wings of an aircraft - as in an aerofoil. Let's use the aeroplane as an example:
If you were to cut a cross section of an aeroplane wing, it would appear to be an elongated comma shape, turned on its side; blunt and round at the front, tapering off to a point at the end. The top of the wing is curved, the bottom is almost flat, with a very slight concave. As the engines drive the aircraft forward, air is forced over and under the wing. The shape and angle of the wing causes the air to flow over the top of the wing more easily than the bottom. This creates an area of lower pressure at the top of the wing and gives the aircraft it's lift.
A sail works in much the same way, only flipped over ninety degrees. As the wind passes over the sail and fills it out, it adopts an aerofoil shape. When angled so that the wind runs across the sail (like an aeroplane's wing), an area of lower pressure is created, pulling the craft in the direction of the 'lift' generated by the sail.
To keep the craft moving forward, a keel is used. A keel is a hydrodynamic device on the bottom of the yacht or boat that counters any sideways force of the wind to keep the craft moving in the desired direction. It also has an aerofoil (or hydrofoil) like shape to generate lift from the water - this is to pull it away from the force of the wind and maintain vertical stability while sailing.
So now with the knowledge of how it all works, sailing all of a sudden seems a lot more appealing! The next thing on my list? Find somewhere with boats for sale! Or at least boats for charter! Having a yacht isn't just a luxury, it's a fantastic hobby. Sailing is a physical and mental activity that can provide a lifetime of enjoyment. As long as you know what you are doing at sea and you're safe, there's a whole lot of fun to be had out on the water.
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