Very cool JRP!
I had a hard time imagining how the ama stayed to windward until I realized that the boat never actually tacks in the conventional sense. Instead, during a 'shunt' the stern becomes the bow and the rudder is then deployed in what was the bow while the jib is then deployed on what was the after stay but after 'shunting' is now the fore stay. This explains why the jib needs to be doused in order to 'shunt'.
Proa - Wikipedia, the free encyclopedia
Yes, it was
very cool. I'm a dyed-in-wool monohull sailor, so for me this was quite a different experience.
I am by no means an expert on proas or sailing them. I don't know a whole lot more than what I've recently learned on the test-sail of Madness
. But I should have discussed the mechanics of shunting a bit more in the intro post. I'm sure that Wiki link does a good job, but I'll just talk briefly about it here for continuity sake.
In many respects, sailing the proa was no different than a conventional boat, mono- or multi-, with a conventional fore-and-aft rig. As you're sailing along, there's the usual heading up and bearing away, trimming and easing, reacting to shifts and puffs, pinching up as close to the wind as possible, etc.
The way it differs is in what happens when it would normally be time to tack or jibe a conventional rig. It's at this point that the proa instead shunts.
Let's say you're sailing along close hauled, and you can see that you won't make your mark on this "tack". So you realize you'll have to take a leg over on the other "tack" in order to make your upwind mark.
Now, instead of turning the bow up and through the wind and tacking the sails over, the proa eases sails and bears away. As the proa bears away to a beam reach, the main is eased all the way to leeward, so it is just streaming there like a weathervane, producing no drive. Likewise the jib is eased and doused. The boat coasts to a stop. It is completely "stalled."
At this point, the working rudder is raised, and the lazy rudder is dropped. The helmsman shifts to the opposite end, takes the new tiller in hand, then trims the mainsail in again -- pulling the boom back toward the end of the boat that previously was the bow. [The boom has two mainsheets affixed to it -- one leading to each opposite end of the cockpit.] This powers up the main again, and the boat begins moving in the opposite direction. Set the jib, trim in tight, and you're now sailing upwind again on the opposite "tack".
You would do the same thing when it comes time to "jibe", except you'd initially bear up toward the wind to a beam reach from a broad reach. After shunting, you'd bear off again.
Bearing away for a "tack" is hard to get used to. Likewise, the idea of completely stalling the boat during the shunt is strange to read about I'm sure. Most of us do not like to stall our boats, losing all forward weigh and rudder control. But in a proa the shunt is a no-nonsense, no-fuss maneuver. The boat just comes quietly to a stop, and floats there very serenely while the rudders are swapped and the formerly lazy mainsheet is taken in. I was expecting controlled chaos during this process -- reading about it sounds complicated -- but it was actually straightforward and uneventful.