Sail and Rig The Tuning Guide
It is generally thought that understanding the dynamics of the sail and rig makes Sailing not only more attractive but also safer too. So not just for Racers.
The latest book on the subject from the Norwegians Klann and Bordal published by BlueOceanMedia sets out to make complex things as simple as possible. In this it succeeds and at the same time provides something for every level of experience. It’s text, accompanied by lots of photos and illustrations comprehensively covers how to set up the mast and rig and in the later chapters how to handle and trim the main, jib and spinnaker for optimum performance. It finishes with useful tips and hints and a trim guide for light, medium and hard wind conditions.
I found the second part of the guide more interesting as it deals with what you can do on the water rather than setting up onshore ( I try not to take the mast out too often). How much weather helm is desirable, reefing the main downwind, the effect of forestay sag and mast bend all provided excellent advice. The page on “The invisible tornado - Vortex” gave me another insight into the cause of drag and how to minimise it. That is more noticeable when the wind increases, the boat heals and the airflow becomes more vertical, and as in an aeroplanes wing vortices develop at the boom and masthead. Apparently flattening the sail at the top and bottom help to reduce the effect as does additional twist... read all about it.