- Foam fibreglass construction automatically complies with the 50L flotation per hull. Each of my hulls has 60L of foam in it. (PS. I don't understand the point of this rule. Is it for safety? This seems pointless with a redundant second hull to keep crew afloat in the case of a big leak, plus only stupid ppl don't wear life-jackets. Or is it to restrict builders/designers to closed hulls, ie. no **** boats? Can someone please explain...)
We must remember that there are multiple ways of building a F16 hull. Not all are using the foam cored laminate method. I myself have a ply hull. Here the ply skin will only provide some 1.5 kg of bouyancy per hull. As such the pure ply hull will barely float itself when submerged. In the past fully glassed hulls have been made and these will indeed sink when filled with water.
The ideas behind many of such rules in the F16 framework is to garantee that the boat remains sailable in case of accidents, so that the crew can sail themselfs to safety unaided. You can't sail a catamaran back with one completely sunken hull, the rig will then by laying on the watersurface. Not always does a crew have a recue boat around. Most of the time the owners will sail recreationally with only very limited help nearby. We wanted the F16's to be safe boats to own and operate. Fast and high performance but still safe and dependable. I agree the damaged baot will sail badly but at least you can limp back into port without outside assistance.
In you case if you can proof that your foam core is closed cell and of sufficient volume then you can satisfy the F16 bouyancy requirement that way. I don't see any reason why you couldn't. You have satisfied the spirit of the rule.
Personally it seems you did it in a smart way because you have used the bouyancy requirement in a constructive way so the weight added by this foam is now utilized twice, i.e. it is not dead weight you carrying around for as long as the hulls are undamaged. In your case you have made the hull skin stiffer as well. I think that an excellent example of how clever engineering can optimize a boat design under the Formula 16 rules. A line of thought I always wanted to engrane in the F16 rules personally. Giving enough freedom in the rules to allow for smart double application of required components. In my own hulls the foam floatation aren't simply floatation blocks without a secondary functions but are primairily the (stiffening) bulkheads and the floatation devices in a secondary sense.
Wouter
