Proafile v5.0 | Updated: Apr 10, 2008

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Proafile is the online journal and portfolio of Michael Schacht, Seattle-based designer and inveterate proanut.


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Total Entries: 170
Total Comments: 223
Most Recent Entry: 04/10/2008
Most Recent Comment: 05/09/2008

Journal | Newest Entries

Rig Options - Schooner

Posted: 03/02/05 | Proas | 0 Trackbacks

Cheers, perhaps the most famous Western proa, was schooner rigged. Since she was so successful, you might think that her rig had something to do with it, and you’d be right.

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.

continued...

The Case for the Steering Oar

Posted: 03/02/05 | Contributions | 0 Trackbacks

By Gary Dierking

Steering is one of the great challenges of proa design. The one who finally designs a steering system that a) shunts easily, b) controls the canoe both while at speed and while stationary during a shunt, c) is hydrodynamically efficient, d) is immune to underwater hazards, and e) is simple and foolproof, will have discovered the proa “holy grail”. Could it be that the Pacific Islanders have already invented such a wondrous device?

My first experience with a steering oar was not auspicious. In Coast Guard boot camp I managed to talk my way into steering one of the big whaleboats used for training and racing. We must have had all the strong guys on one side as my best effort was not enough to prevent ramming one of the other boats; causing an automatic disqualification and my demotion to rowing guy. It took quite a few years before I realized that a steering oar is much more than a rudder. If I had used the oar function I could have avoided the collision.

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The Zen of Proa

Posted: 03/01/05 | Contributions | 0 Trackbacks

By John Dalziel

When you stop to think of it, sailing and sailboats are a rather peculiar passion, one which non-sailors rarely understand. We are often asked: why sails; why do we not simply use an outboard? We have, of course, quite a number of personal responses, which are essentially statements that we enjoy it. But beneath that lies another, broader truth: within many hobbies such as sailing lie important reservoirs of alternative knowledge our culture, usually for no expressed reason, feels necessary to keep at hand, even in the absence of obvious purpose.

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Testing With Models - II

Posted: 03/01/05 | Proas | 0 Trackbacks

From the Proafile Archives. Originally posted 1999

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

Posted: 03/01/05 | Proas | 0 Trackbacks

From the Proafile Archives. Originally posted 1999

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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