Design Contest Entries  


Duckworks/Small Craft Advisor
- Design Contest #7 -

Class IV Everglades Challenger

ENTRY #6

Bedlam

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Statistics

LOA
-
26ft
Max Beam
-
11ft
Min Beam
-
8ft
Draught
-
3ft 6in/9in
Sail Area
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130 sq ft
Race Displacement (at start)
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800lbs
Boat weight
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275lbs
Crew weight
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350lbs (2 @ 175lbs)
Stores
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175lbs
Sail area displacement ratio
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24
Displacement length ration
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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!

SAILS

EPOXY

GEAR