Sailing Multihulls Part 2: The Disadvantages
Disadvantages-- In serious wind and seas, a monohull sailor can,
if absolutely exhausted and no longer able to steer, strike all
sail, lock all hatches, and go below to wait it out and hope for
the best. A well-found boat will most likely allow this. The
boat will roll around like a cork, and even if it rolls 360
degrees it should be ok, as long as the mast doesn't break off
and put a hole in the boat. A Multihull in huge seas, however,
must always have a helmsman, or some other way to keep the boat
pointed into the waves. Without this, the boat will end up in
the wave troughs, with the waves beam on; this is an invitation
to capsize. Knowing this, the ocean going sailor should be
prepared with a parachute sea anchor and with attachment points
for it on the boat that are absolutely bombproof. Properly
deployed, a parachute anchor will allow a multihull to ride out
a hurricane in near comfort, as it keeps the bows pointed into
the wind and waves and with several hundred feet of line led out
to the sea anchor, there is no jerking or lunging on the line.
Once the sea anchor is properly set, the crew can go below and
safely wait out the storm. This assumes that there are no
dangers, such as a landmass or reef systems, lying in wait
downwind. Plenty of sea room is needed for these manuevers.
Marinas-- Finding space in a marina for a multihull is not
nearly as easy as it is for a monohull. They require either an
end space or a double berth, which will likely cost more than a
single.
Weight constraints -- Since a multihull sits on the water
instead of in it, unlike a keel boat, the payload, or weight
carrying capacity of the boat, can not safely be exceeded. A
catamaran, with essentially two full boats in the water, can
carry more weight than a trimaran of the same length, which
consists of one full hull and two floats. A 35 foot monohull can
carry much more weight in stores and equipment than a 35 foot
trimaran, and this is a consideration when provisioning a boat
for cruising. The cruiser in a small multihull may find himself
reprovisioning along the way more often than the cruiser in a
small monohull.
Trailerability-- Large multihulls cannot be shipped over the
road, due to their wide beam. Only some of the smaller, folding
designs will allow trailering.
Haulouts also can be more complicated for multihulls. There are
yards that have travelifts wide enough for them, or cranes to
lift them, or railways to pull them out of the water on tracks,
but these yards are fewer and farther between than those that
can't handle the extra wide beam.
Conclusions -- It seems that outside of a couple of minor
inconveniences, a multihull is the only boat that makes any
sense. If this is the case, why doesn't everyone have one? There
are a couple of reasons. One is the unfortunate reputation they
earned early on in their evolution. The other is the expense
involved in achieving ownership of a quality cat or tri. These
boats are expensive to build, whether as one offs or as
production models. With a trimaran, 3 hulls (amas) and crossarms
(akas) to connect them all together are needed. For production
this requires expensive tooling up for a company to invest in
even before they ever get a boat on line. There are also a lot
more materials needed to build two or three hulls than are
needed for the one finished hull of a keel boat.
Other than a production model the buyer has the option of having
one custom built by a reputable yard or of building it himself.
Neither of these options is cheap, fast, or easy.
There are used multihulls on the market, and there are a lot of
good ones out there. There are also a lot of not so good ones.
It's critical to hire an experienced multihull surveyor to be
assured that the boat was built and maintained properly and is
sound.