Duckworks/Small Craft Advisor
- Design Contest #7 -
Class IV Everglades
Challenger
ENTRY #6
Bedlam
Statistics
LOA |
- |
26ft |
Max Beam |
- |
11ft |
Min Beam |
- |
8ft |
Draught |
- |
3ft 6in/9in |
Sail Area |
- |
130 sq ft |
Race Displacement (at start) |
- |
800lbs |
Boat weight |
- |
275lbs |
Crew weight |
- |
350lbs (2 @ 175lbs) |
Stores |
- |
175lbs |
Sail area displacement ratio |
- |
24 |
Displacement length ration |
- |
20 |
Description
Bedlam is a 26ft ultra lightweight pacific proa.
A couple of factors pushed the design in this direction.
The first of these was the latest record for the course
of 66 hours. Set by a class IV boat, in what was probably
close to optimal conditions. The fact that much of
the course doesn’t require a boat that will
win a tacking duel, but rather one that is weatherly
and fast in a straight line. And the availability
of high quality offshore sailing clothing, designed
to give the wearer some small comfort in extremely
adverse conditions.
Last years winning Core Sound 17’s average
speed over the course was about 4.5 mph. This is an
exceptional average, and one that would be hard pressed
to exceed with any monohull that meets the “small
craft” designation that seems to regulate class
4 boats. Multihulls should easily be able to maintain
this average, and even increase upon it, but with
them the complexity rises and/or compromises are made
in the design. Hence the proa design. Proa’s
have exceptional performance potential in a straight
line, and are also very simple devices, carrying all
their rigging loads in the leeward hull. Because of
this their weight is much lower than other multi’s
with the same potential, and I felt that a proa with
a low drag ama would stand the best chance if the
race devolved into a paddling contest between the
class 4 boats.
Bedlam’s vaka and ama are both strip planked
in ¼ inch bead and cove strips of red cedar,
or another appropriate wood. This is then sheathed
inside and out with 6oz fiberglass cloth set in epoxy
with an additional strip of kevlar down the center
of both hulls to provide abrasion resistance. To achieve
the design weight of 275 lbs. of boat weight the builder
will have to be careful not to allow any extra weight
to creep into the build. The beams are simple carbon
fiber tubes that are bonded to the hulls. They telescope
together with a basic cam locking mechanism to lock
the boat to a set beam.
The foils are P30212 bi-directional laminar flow
sections made up of a foam core covered with fiberglass.
They are mounted to outriggers that kick up in either
direction by mounting to the circular beams. These
are locked into position using a similar cam locking
mechanism that will hold the boards in the vertical
position while allowing them to pivot if they hit
something. The other advantage of this is that they
can be swung around completely so that they are positioned
vertically on the trampoline between the beams, decreasing
the draught to 9 inches or less and allowing paddles
to be used from the dual cockpits in the vaka. The
foils work as both rudders and dagger boards. When
sailing, the aft board is locked in its fore and aft
position and the forward board becomes the boat’s
rudder. When shunting these two are reversed, the
new sheet is pulled in, and off we go on a new tack.
The rig is a simple una rig using an extended sailboard
mast with a track bonded onto it to carry the sail.
The mast drops over a stub extending vertically from
the vaka, and pivots on this stub. The boom is fixed
in relation to the mast, therefore the whole rig pivots
when shunting or trimming sail. In case of a light
wind deficiency a code 0 or drifter could be set flying
on an additional halyard. This sail would have to
be doused when shunting, but is shouldn’t cause
too much difficulty in the light airs it is intended
to assist in. For paddling, the whole rig lifts off
and is secured to the ama, clearing the vaka for paddling.
The vaka has two cockpits for paddling, these are
separated from the rest of the hull, with spray skirts
for paddling and more secure solid covers for sailing.
The fenders used to role the boat down the beach at
the start are stored in these, as well as the paddles
when they are not needed. The section between the
beams is where the water, food and other stores are
kept. It is accessed through two touring kayak style
hatches. The ama is designed for minimum drag, but
is sized to have both crew standing on it without
submerging. It has a 6ft long seat designed into it
between the two beams. The seatback is a simple fabric
covered aluminum tube that folds down into the seat
area to minimize windage while paddling. Crew, when
they need a rest are intended to curl up on this seat
in their survival gear and nap.
Bedlam comes by its name, because when my wife saw
the drawings she said that one would have to be crazy
to race it! This is probably true, however at my young
age (30) I can just imagine screaming down course
at 10 – 15 knots with the ama just kissing the
wavetops. A rooster tail coming off of the back of
the vaka and foils, and all the other boats receding
into the distance behind. I think I could manage that
for the two and a half days necessary to set a new
record!
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