Anti Stuff Fins
In the mid 90s I drove a Frode 19 in what used to be 1.3 Litre. It had a terrific pair of anti stuff fins made from aerofol shaped aluminium at probably vaste expnse by Mr Pascoe and his team at Vulture Ventures.
They did actually work quite well, we even managed to bend them once.
Its all down to hull shape, they are all a compromise; To go fast into a big head sea you need very little forefoot and a fine bow to stop the waves deflecting the boat to far upwards, a little water in the bow tank, level trim and commitment should see you just cut the top of the waves off and run level. Going downwind a boat like this will need even more commitment as it does not have the volume in the hull forward to aid the recovery as the boat travels down a wave, hence anti stuff fins; first used by Fabio, "cheat to win" on some of his finer shaped monos. He even put them on some of the Iveco cats if I recall correctly.
When we built the Frode 23s for racing in about 1992 we put small alloy rails down the chines for the first 4 feet forward as they would aid this process without making the bow too full. Again you needed commitment and to be under power to make them work, back of and they would stuff. Many of the owners couldn't get the hang of it and so weren't as fast as they could be and complained that the boats wouldn't go in a following sea !
So in conclusion yes they do work, if they stick out far the forces involved can be immense so make them strong, and tie them together inside the hull. You need to know how to use them as well. don't put in too much angle of attack or you will tear them off with possibly catastophic damage to the hull.
Mr F you been pokin around in his cockpit then??
