Deep-V hulls get their name from their
shape in cross-section: ;e more V angle
they have, the more stable they are.
CATAMARANS. Unlike the deep-V monohulls, catamarans have two separate sections of
hull, called “sponsons,” that run the full length of the boat and ride in the water. ;e center hull
section is raised out of the water and creates a tunnel area between the sponsons, reducing
the amount of drag from contact with the water. Additionally, the tunnel traps air as the boat
moves forward, which lifts the hull out of the water and further reduces drag at speed. ;e
combination of the two makes these hulls almost literally “fly”—just skimming the water’s
surface and allowing amazing speeds! Because these hulls ride just
at the water’s surface, they are more sensitive to water
conditions and will tend to jump and bounce around
more as the water gets rough.
Catamaran hulls feature two sponsons that run
the full length of the hull. Combine them with the
tunnel area between and you get a boat that flies!
Hydroplanes are designed to “fly” just above the water’s
surface. Once up to speed, only the sponsons, the rudder, and
the propeller are in the water.
HYDROPLANES. Hydroplane hulls come in two styles: full-bodied hydroplanes, often referred to as “sport hydros,” and
outrigger hydroplanes, or “riggers.” ;ese boats are designed
to skim the water’s surface, with only the sponsons, the
rudder, and the propeller in the water.
Sport hydros resemble the full-size limited or unlimited
hydroplanes you might see on TV, and consist of two
sponsons in the front that only extend back to just forward
of the hull’s midpoint. ;e rear section of the hull, or
“afterplane,” is generally flat from the sponsons back to the
transom. Some designs have small rear sponsons as well. ;e
full-body acts to increase aerodynamic lift, helping to fly the
boat above the water’s surface.
Outrigger hydros also have front sponsons, but they
are attached to the center section of the hull using rods,
usually made out of carbon fiber. ;ese boats resemble an
airplane fuselage with sponsons “out-rigged” on each side.
Outriggers are the most pure hydroplane design and are
capable of the highest speeds. As such, they are exclusively
kit and custom models, not RTRs.
;e majority of RC boat hulls are made of either ABS plastic
or fiberglass, with plastic being the most common option.
ABS is the most common plastic used, and plastic hulls are
common because the material is lightweight, easily molded,
and inexpensive. Most plastic hulls are made using the same
process as RC car bodies, wherein heat-softened plastic is
pulled over a positive mold.
As you move up in size,
fiberglass becomes the
construction material of
choice because of its strength
and the ability to customize
hull thickness by varying
the layers of fiberglass
cloth. Unlike plastic hulls,
fiberglass hulls are laid up in a
negative mold, which allows
them to better reproduce
sharp-edged hull details
such as strakes or steps.
;e downside of fiberglass
construction is cost and
weight—both are higher
compared to plastic.
Boat hulls can be made from injection-molded plastic, thermoformed
plastic, or fiberglass. Fiberglass is has a great combination of strength
and low weight, which makes it a popular choice for a lot of hulls.