Weather helm

Olympic sailor Paul Brotherton advises on how to deal with it
First, get in touch with your sailmaker to find out the working mast bend range for your mainsail. This is fundamental, although a lot of good sailors do not have a handle on this. Your sailmaker should be able to tell you what sort of mast bend you should be setting up for the sail that they have produced. Unfortunately, that is only a starting point, because setting up static mast bend on the shore is not the crucial measurement. What really matters is the mast bend you have while you are actually sailing, and that can vary depending on variables such as crew weight. For the Youth Worlds in the 420, we set up the boys' rig with a straighter mast than the girls, although when they were sailing the resulting mast bend would be the same. It is important to find out the flexibility of the mast. For instance with the 470, many sailmakers produce two distinct types of mainsail - one for a stiff section such as the Proctor Epsilon and one for more flexible masts such as the SuperSpar M7 or the Proctor Stratos. An Epsilon-style mainsail is cut with minimum luff curve, so if you put it on a flexible mast the chances are the mast will bend too much for the sail and you will see nasty creases coming away from the centre of the luff. These are so-called starvation creases and they are a strong sign that all is not well with your set-up. This can happen even if you are using the right sail and mast combination but allowing too much bend to creep into the mast set-up, either through setting up your spreaders incorrectly or through insufficient chocking at deck level. On the other hand, putting a sail designed for a flexible mast