By John C. Harris
Proas are the ONLY sailboats that can be reliably stopped, parked, and reversed on whim. I have never been in any sailboat type that I’d rather work into a crowded harbor under sail on a windy day.
Having gotten the handling peculiarities out of the way, everything else about the proa configuration is absolutely compelling. No multihull can boast a lighter or easier-to-engineer structure. This pays off for the home-builder, who is spared the need for high-modulus crossbeams and attachments. There is simply less to build than either a trimaran or a catamaran.
Proa sailors enjoy other handling advantages. Instantly noticeable under way is the easy motion. With the outrigger just skimming the water (unlike the trimaran’s hard-pressed leeward ama), the lack of nervous pitching is easy on the crew and keeps airflow attached to the sails. And the unusual rig geometry of the Brown-styled proa sloop opens a huge slot between jib and mainsail, making this style of proa exceptionally close-winded.
Madness is built using techniques that are state-of-the-art for about 1975. 6mm okoume plywood panels are stitched-and-glued together very quickly and sheathed on both sides with ordinary plain-woven e-glass. Every part in the boat is pre-fabricated on the bench. The prototype, built at Chesapeake Light Craft, was whizzed out on a CNC machine, making an affordable kit possible. Plans builders get full-sized patterns for most of the hull parts. Thanks to the fore-and-aft symmetry of a proa, the longest pattern is just over 15 feet.
Even without resorting to exotic materials, a very light hull is the result. Slung from my digital scale, the stripped main hull is right at 500 pounds. The outrigger, crossbeams, rig, and outboard account for another 500 pounds.
With sails, 4hp outboard, and basic cruising gear aboard, Madness weighs about 1400lbs, and compares directly with a Farrier F-24 in terms of SA/D---at a fraction of the cost and building complexity.
Something is gained, and something is lost: proas don’t have a lot of volume for their length. However, the payload is just under 1000lbs, which will allow two uninhibited adults to cruise for months, or three to race the boat for a few days.
There are two berth flats fore and aft in the main hull, plus a wide, comfortable berth in the lee “pod.” On my boat, Madness, one of the berth flats has been converted to conceal a chemical head, and above it is mounted a lightweight galley that slides out of the way.
In good weather the crew will sometimes sleep on the trampoline.
The ama contains self-draining lockers for lines and fenders.
The skipper drives the boat from the motorcycle-sidecar-like cockpit adjacent to the cuddy. Draglinks are led
from the tiller yokes to the cockpit. The crew occupies a comfortable “park bench” style seat on the trampoline to windward of the outboard sled.
The lee “pod” makes capsize very difficult. In four proas featuring a lee pod of similar proportions, Russell Brown has accumulated ocean crossings and 30 years of coastal sailing without managing anything more than a few knock-downs. Additionally, the outrigger contains up to 700 pounds of water ballast. The ballast tank is filled using very simple and reliable plumbing: a bucket through a deck plate. It’s emptied with a bilge bump. Sea trials of Madness revealed that water ballast will be necessary only when racing or showing off. Otherwise, a reduction in sail keeps the boat flat.
The mast is stepped on the windward edge of the cockpit, with all halyards right at hand. Winches and sheet cleats are located on the flange that stiffens the mast bulkhead. Because the mast is mounted 39” to windward of the main hull’s centerline, struts are required to sheet the mainsail.
The jibs are mounted on furlers. In tacking, the current jib is rolled up, then doused completely to allow the boom to swing 180 degrees onto the new tack. Then the “new” jib is hoisted and unfurled. The mast may be rotated through about 90 degrees for best performance.
Because of the mast location, there is no danger of losing the mast in an aback situation because it is supported by stays to the four corners of the boat. The very broad staying base allows a lighter mast, with spiraling gains in weight and complexity.
Provision is made for an asymmetrical spinnaker.
Madness was fitted with the square-top rig shown in the drawings. A smaller “cruising rig” is meant to inspire builders to look for used masts and sails, which will cut the costs dramatically. Madness’s carbon stick and Vectran sails cost more than the entire hull!
An outboard of 2hp to 5hp is mounted on a retractable sled beneath the crossbeams, convenient to the skipper. Sea trials showed 5 or 6 knots with a 2hp in calm conditions, and up to 8 knots with a 4hp.
Madness is completely demountable for road transport. Six easily accessible bolts in the main hull and four bolts on the outrigger fasten the crossbeams. The trampoline is rigged with bungie cords for quick release, and two pins disconnect the outboard sled. With the main hull at 500lbs, a group of friends can lift it onto a trailer. It measures 8’3” at the widest point, making trailering easy behind a relatively small vehicle. Total trailer weight is less than a Montgomery 17 pocket cruiser.