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Sail shape, discussion in detail
I have a 42ft, 8500kg IOR Racer with a masthead rig.
My biased perception of the sail wardrobe for a yachts like this is:
Genoa1 Light: 1-5m/s, 150%
Genoa1 Heavy: 4-8m/s, 140%
Genoa2: 8-12m/s, 125%
Genoa3: 12- m/s 110%
G1-G2 should go up the top of the forestay for best aspect ratio. G3 should be somewhat reduced
I think conventional wisdom says that G1L should be very flat. G1H should have more depth, G2 same depth, and G3 flater again. The idea is that very light wind need a flat sail (G1L) to be able to follow the sail around. A bit more wind makes it possible to get more force/speed with a deeper sail (G1H). Even more wind just reduces the sail area (G2) and finally with even harder wind it is time to reduce both the area and the heel by making the sail flater.
My question is. How much.
-the G1L be 10% or 12% deep at the top or something else?
-The G1H be 14% or what?
-The G2 be 14%?
-The G3 be 12%?
What should the relation be between the depth at the bottom and top of the sail and the position of the maximum depth of the sails. Should the position of maximum depth vary on the different head sails? I think it should be around 35-45% for a head sail but were should it be?
How much twist should there be in the different head sails.
The figures above are guesses? I would find it very interesting to have a discusion about this. Also suggestions for good books or websites on this topic is welcomed.