FAQ

1. Which has more lift, symmetric or asymmetric sections?

How long is a peice of string, in general aysmetric hydrofoils are designed to produce more lift with less drag. However if it is only lift you are looking for then the standard NACA00XX sections are pretty good. For instance the symmetric NACA0012 section produces the same maxuimum lift as the equivalent and popular asymetric NACA2412 section. Both have a maximum lift cooeficient of 0.15. The difference between the two is that the NACA2412 section has less drag for that lift.

So if your aim is only to prduce lift then you can stick with a symmetrical section but if you are racing someone in a similar boat then the sailor with the aymmetric foil may be faster than you!

2. What are the material properies for strength and deflection calculations?

For both Modulus of Elasticity is 69GPa and Tensile Yield Strength is 145MPa

For the FF27 the second moment of area is roughly 200,000mm^4 (calculation by hand!)

For the FF13 the second moment of area is roughly 10,000mm^4 (calculation by hand!)