Just a quick note regarding mast rotation and the diagram from Tom Speers site (it's worth checking out his site, lots of good information there. Tom works as an aerospace engineer, and is highly competent within his field).

The foil used as an example is a Clark Y foil, and methinks it is a bit to full forward for a sloop rig. So dont take that example as holy writ for all boats/sails.
The example is taken from an article about wingmasts and their design, so please take time to read his criteria on why he used the Clark Y foil before you go racing with your mast rotation set to 53degrees


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