thought

Originally posted by mike ellis isnt it short foils which stall easier barty

To over simplify a *very* complex subject then, for the same area and section, the longer and thinner the centre/daggerboard then the lower the drag will be, the lower the range of angles (ie leeway) it will operate efficently at, and the more easily it will stall. This is complicated by the section being dictated as much by making the board thick enough to survive capsize recovery and a billion other factors.

One of the big limits on the foil properties is that it needs to work effectively coming out of tacks with tons of leeway and very little speed. Very low drag foils are rarely good at this and need more skilled handling, and you can readily reach the point where you lose more tacking than you gain in between tacks with reduced drag. For example learners boats need thick and relatively low aspect ratio foils because they're easy to sail with, don't break if the crew jump on the end, and the drag is less of an issue.