* Hobie 16's will float with both bows broken off at the crossbeams. It's like towing a wind chime though

* The pieces of old soft Gougeon Tornado's float after the boat breaks up. One nice thing about wood.

* Hobie 18's will sail with the first foot of both bows broken off. They do not point very well though.

* Reg White Tornado's will sail with one hull full of water and half the skin missing and only the sub deck holding the other togather. They go faster than a Hobie 18 with both bows broken off too.

* Marstrom Tornado's float with both hulls full of water. They reverse pitch pole if you are not careful though.

* H20's, P18-2 & N5.8 float with no bottoms. Hitting rocks or oyster reefs is a bad idea.

I seem to remember a couple of requirement that boats not sink. One was a US safety requirement and the other a general racing requirement from IYRU.