What's a Trimaran?

A trimaran is a boat with three hulls.  Unlike a catamaran, which has two equal-sized hulls, on a trimaran generally the center, or main hull, is bigger than the hulls on the sides (usually called floats).  The first boat that resembled a trimaran was most likely built by ancient Polynesians, although it was much more common for them to use boats that resembled catamarans because they were comprised of a dugout canoe with an outrigger for stability.  The outrigger was usually a log, and it was connected to the canoe with two smaller branches or saplings.  Today the floats are connected to the main hull by beams, usually made from a composite of fiberglass and/or carbon fiber.

Why build a boat with three hulls?  What's wrong with just one or two?  First, there's an enormous difference between a boat with one hull and a boat with more than one hull.  A sailboat with one hull must rely on something dense and heavy to counteract the tendency of the wind on the sails to push the boat over on its side.  This something is called  "ballast", and usually resides in a fin sticking down from the bottom of the boat, called a "keel".  Ballast usually accounts for about half the total weight of the boat.  If you can get rid of the weight of the ballast, your boat is going to go much faster.  (Not to mention be a bit safer, since its tendency to sink if it gets a hole in it is reduced or eliminated).  This is the basic idea behind a multihull.  You achieve stability via form rather than via ballast.  Since the multihull is so much wider than a monohull of comparable length, it has much greater resistance to tipping over, so it doesn't need ballast.  (The downside is that when it does flip over, it stays that way, unlike a monohull, which if it doesn't sink as soon as it flips over, might possibly roll back upright.  Choose your poison.)  The difference between a catamaran and a trimaran is much less than the difference between either and a monohull.  Typically, the center hull on a trimaran has whatever accomodations exist on the boat: anywhere from a cuddy to hold lunch and your wallet to a full living space.  The smallest catamarans have no dry space whatsoever, and the largest have multiple berths (places to sleep), heads (places to poop), and other living spaces, divided between the two hulls.

Because of the history, some sailors insist on using the Polynesian terms for the parts of the boat.  Hence they call the main hull the "vaka," the beams which connect the main hull to the float are referred to as "akas," and the floats are "amas."  This is pretentious.  After all, a modern trimaran has about as much in common with a Polynesian outrigger canoe as the Emma Maersk does with the Nina, Pinta, and Santa Maria.  At least they take their silly conceit only so far: they still refer to the sails as "sails," the rudder is still a "rudder," and so on.  I think it's odd that they would pick some words and not bother to research the Polynesian translations for others.  And it's frustrating because the words are all so similar, so whenever I'm reading one of their Internet posts and I come across the word "ama" or "aka," I always have to stop and think: is that the beam or the float?

Granted, we all like to talk like pirates once in a while.  But just the same, I think most of us find it a bit odd when confronted with somebody who insists on talking like a pirate all the time.  I think Wayne Curtis puts it best in his book And a Bottle of Rum:

"People in period dress always unsettle me.  I dread the moment they make eye contact, then snap into historic character and start speaking with a surplus of enunciatory gusto about an esteemed gentleman you've perhaps heard of by the name of Thomas Jefferson or some such thing."

The members of the "aka camp" unsettle me in the same way, for the same reason.  At least I only have to deal with them on the Internet, and aside from their jargon they seem to be a pretty good bunch.

Ian Farrier sums it up from the designer's perspective: "One other thing, I have always used the terms floats, beams and main hull. I have never used ama, aka, or vaka, as these are terms from another era, and are too easily confused with one another. I have had emails from owners who have been having a problem with one of their akas, only to find they really meant their ama, or was it vaka, and then what about the haka? I would much rather keep terminology modern, simple and understandable."

So why do some trimaraners insist on this palaver?  Beats me.  Maybe they just think it makes them sound erudite, but I suspect it has more to do with the general sailing community's attitude towards multihulls in general.  Historically, multihulls have been shunned by the yachting world because they're too fast, and tend to spank the multimillion dollar fully-crewed toys that you see in Newport and on Long Island Sound.  So using the archaic language is a way to remind everyone that trimarans, in one form or another, have been around for 4000 years or so, long before the first Europeans decided to see who could go fastest by putting rocks in the bottom of a tub.