Entries | Proas

Rig Options - Crab Claw

The Traditional Oceanic sprit rig (aka crab claw) has, in Western eyes, been considered a romantic if not particularly effective rig that most likely compared to the Mediterranean lateen in aerodynamic performance. That is, until famed sailboat aerodynamics researcher C. A. Marchaj published this startling graph in his research paper Planform Effect of a Number of Rigs on Sail Power.

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Rig Options - Bolger

The Bolger proa rig echos the unique symmetry of the proa: the airflow reverses direction during a shunt, just like the water flow on the hull. The rig has many powerful advantages that have led to a 50-year series of attempts to develop it into a useful sailboat rig. It is a wonderful example of the maxim: "In theory, theory equals practice. In practice, it doesn't." Though the rig has become known in proa circles as "The Bolger Rig" due to the fact that it was Bolger's proa cartoon that became widely known, the rig in fact was invented in the 1960's by members of the Amateur Yacht Research Society (AYRS) who thought so highly of its potential to christen it the "AYRS Sail".

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Rig Options - Gibbons

Writer and naturalist Euell Gibbons was living in Hawaii and dining on the jungle flora and fauna in the 1950's. He soon realized that "an island is a small body of land surrounded by the need for a boat", so he set out to build himself one. Euell had been a professional boatbuilder, so he knew something of what he was about.

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Rig Options - Balestron

Of all the Western rigs that have been tried on proas, the balestron rig (also known as the Aerorig®, balanced rig, swing rig, and EasyRig®) has the most promise. This rig has been around for decades, and is slowly making inroads into the notoriously conservative yachting establishment.

Whatever the rig's advantages for tacking craft, they pale in comparison to what it can do for proas; it makes shunting as simple and stress-free as tacking your Hunter 32 around the bay. This rig makes single-handing a big proa a reality, and opens the door for proas to become a serious alternative for the cruising sailor.

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Rig Options - Sloop

Rigging a proa as a sloop is a true blending of East and West. The proa is considered the pinnacle of Pacific canoe design, and the sloop is often considered the finest invention of Western "yachting". Brilliant in their own context, what happens when we creatively recombine their DNA?

First consider the sloop. Beautiful, efficient, and handy, the sloop has been the darling of the yachting world for going on one hundred years. Refined over the years, and lavished with the latest hi-tech materials, the rig is versatile enough to please all-out racers and laid-back cruisers. When set up with a self-tending jib, the rig is simplicity itself to tack, needing only a gentle hand on the tiller to guide the boat through stays. When rigged as a racer, there are enough sails to change, winches to grind and strings to tweak to keep a large crew very busy. The rig works for small day sailors all the way up to 100' mega-yachts.

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Rig Options - Schooner

Though the schooner has several good points, the most important one as far as proas are concerned is the ability to vary the fore and aft CE (center of effort) by trimming the sails. This ability cannot be overstated enough, in my opinion. Proas are, by their nature, "rudder-challenged". That is, the necessity of shunting makes operating a rudder a problem. You may think that I am talking about the problem of shifting the rudder from one end to the other during each shunt. Though this is an issue, twin rudders, perhaps counter-rotating, at each end of the hull, can handily solve this problem. No, the bigger problem is that a proa must come to a complete and dead stop for each and every shunt.

As any sailor knows, allowing a sailboat to come to a stop is allowing it to get out of control, because with no water flowing past, the rudder is rendered useless. All Western craft are fundamentally designed with the unspoken assumption that the craft is NEVER to come to a complete halt while sailing. When this does unintentionally occur, the boat is said to be "caught in irons" - a colorful expression that illustrates the Western sailor's dread of the situation.

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Testing With Models - II

After my exciting but ultimately unsatisfying flirtation with anti-heeling Bruce foils for my proa scale model, I went out and bought my first computer. We all know what a huge time sink that is, so the proa and any model testing pertaining to it went onto a very remote back burner. This turned out to be perfect timing, since once I discovered the internet, I gradually found other people who were also interested in proa design and development. (All three of us!)

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Testing With Models - I

After the disastrous first sail of my 26’ proa Rozinante, and after waiting a suitable time for my emotional wounds to heal, I decided I needed to do some research and testing. Research was easy, since there is practically nothing out there to read on proa design. One notable exception is the Amateur Yacht Research Society (AYRS) which has published many a paper about proas over the years, and is one of the few yacht design organizations that treats proas as a legitimate area of interest. I became a member post haste.

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