Originally Posted by SailFastTri
2) Capsize resistance: Trimaran ama buoyancy of 3x displacment or more (not unusual in more modern tri design) along with typically wider beam/length ratio compared with a cat translates to great capsize resistance. Note I didn't write "greater" because that's not a rule
and other factors are to be considered in any comparison. One must get specific about comparisons.
typically tris are wider this is true, but the moment they work on is beam over 2 (B/2) because the main hull is the weight, the wetted area, carries the rig and is hence the pivot, only half the beam works in its favour.
Whatever way you figure out the sponsons volume its going to be less than a catamaran hull therefore offer less buoyancy and less resistance to capsize.
As boat lengths come down, the catamaran offers less advantage while at the same time offering variations of less, to no accommodation. But such cats have less wetted area, will tend to pull their windward hulls higher than the waterline, have less total wetted area so boat speeds go up.
Aerodynamically it is easier to have a stayless and vastly more aerodynamic rig in a tri because the mast
can be supported within the depth
of the largest hull. You cannot do the same on a cat without adding weight to the crossbeam structure and likely reducing sail area, both measures are counterproductive.
Originally Posted by SailFastTri
Nobody has yet mentioned joy of sailing. The better "feel" of a tri comes from the fact that it has some heel so it's easier to "read" how hard you're pushing the rig, and tune in with your senses as monohull
sailors know (but at higher performance in most cases). The boat the OP showed is more like a cat with exaggerated nacelle, not like most tris. It may be technically a tri because it has 3 hulls but I would expect it to sail more like a bloated cruising cat because most of its displacment is in its amas.
most often tri designs keep a sponson out of the water
, flying a hull makes them faster because they have less wetted area. So underwater
we have a version of an atlantic proa where you would expect it to be lighter, and therefore on the same sail area faster.
Since Farrier, it has also been realised that tris are more capable of being folded which is especially useful for trailering. Here a tri doesnt need or have the ballast of a mono, and the package can generally offer good maximum boat length and still be able to afford the full share of stability at modern beam length ratios within its folding mechanism. As we concluded earlier it should also be quicker to rig/de-rig with a stayless mast
The asset allows them to be launched off the trailer; conveniently and quickly unfolded as needs be within the confines of a busy ramp
and still be able to motor
away. In these sizes they are very definitely the most all round useful of boats as demonstrated by the current
resurgence of competitive trailerable trimaran production boat designs.
The design we are offered in #1 gives considerably more hull volume, but at the expense of a lot more wetted area. I think it as close to a cathedral hull than either a cat or tri and usually best disposed to power craft.
Unless we can see some opposing data pretty much the worst of all worlds.