>> http://www.stabilityyachts.com/ >> > > This vessel looks very cool and unique in certain aspects, but they're talking about a 63 footer that sleeps 5? It look like it has the cabin space of a 40-footer. Compare it to the other 60+ footers out there for accomodations. Plus, it looks like it might be a great design for choppy seas, but for truly rough water? Any comments from designers? Malcolm? I cannot imagine comparing my skills or sensiblilties to those of Mr. Tennant, or any other credible designer -- however... It appears to me that this design is intended to bring 'reserve bouyancy' to some irreducable minimum, in hopes of finding a similar goal as that of the 'wave piercing' hull, namely that whatever the wave, the hull lifts very little or ideally not at all. That's great -- and provides the landlubber's ideal mentioned in their web piece of no wave motion -- so long as the wave is small enough to clear the bridge deck. Much larger waves, as you seem to have suggested would indeed contact the lower surface, or indeed the upper surface of the upper, or bridgedeck portion of the hull, and my intuition tells me that the result would not be very pleasant. Ultimately, it may not even be survivable. Look, if you will, at the downward sloping deck of the forward portion of the cabin structure (the one with the water slide shown on the web page), and imagine for a moment that a ten, fifteen or twenty foot wave has been taken on the bow. In the large wave situation mentioned the submerged flotation hulls would continue on the level track so envied in a small chop situation, and the wave would catch that downslope forward deck section with tons of moving water, potentially even pitchpoling the boat. Not good. Am I missing something important here...? You have also pinpointed a significant liveablility issue. Without access to space in the traditonal catamaran hulls, the remaining space will be high off the water, and limited to the rectangle provided in the bridge deck. Per the photographs, there is at least one of these beasts about. Wonder how the real performance compares to my idle ranting? Gary Bell, AKA ' Mr. Science'

Gary, There are a fair number of wave-piercing cats out in the real world. As the old saying goes, all boats are a series of compromises. Ultimate survivability in huge seas is not the most practical design parameter in most cases...otherwise we'd all be tooling around in the aquatic version of a tank. Check out these boats: http://www.goldcoastyachts.com/wavep.htm Bob Deering Juneau, Alaska