I recall America's Cup boats that had the "fish scales" added in plastic to the outer layer. They seemed to think that helped. I do not recall if they won...

> Solid/liquid friction drag (as opposed to wave generation drag) is
> generated in the water not at the water/hull boundary. Materials do not
> affect the friction drag. Surface finish will. This is different than
> solid/solid drag where the materials and the surface finish affect the
> drag.

> Surface hardness can be improved more by adding glass to the fill coats
> than by adding graphite. Simply lay a top layer of lightweight glass cloth
> (2 or 3 oz) when you lay your regular cloth, and sand it smooth (about
> halfway through the top layer). Not only is it harder it is transparent.