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Old 11-09-2010
rgscpat rgscpat is offline
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Tall ships versus small

Tall ships are built very differently than cruising sailboats. I may over-simplify, but the naval architecture fans can fill in the details and provide a more accurate answer to follow-up on my speculating.

Most modern blue-water and even typical production monohull cruising sailboats have a good righting moment that will help the boat pop back up from a knockdown, thanks to deep fin keels with heavy lead or iron ballast.

Old time sailing ships, however, relied on their beam and mass (and perhaps relatively less powerful sail plans or the ability to actually remove the upper masts and sails before entering an area of expected heavy weather) for capsize resistance, and didn't have deep, heavy metal keels to provide righting moment in the event of a severe knockdown. Often, their ballast consisted of loose rocks that could be dumped overboard in order to make more room for cargo. A great fear in the olden days was cargo, ballast, or cannons escaping confinement and battering the ship's hull from the inside. A more modern tall ship designed to train young people would presumably have some form of fixed internal ballast, but it still wouldn't likely have the sort of righting moment of a deep-keel boat cruising sailboat.

There are also other differences, notably in the complexity of the rigging on a sailing cruiser versus a tall ship. The skipper and crew on a small cruiser can often pop the sheets out of a clutch or cam, dump the traveler, and even roll up a roller-furling headsail, within seconds, to relieve excess wind loads. Good cruising and racing skippers are always alert and ready to ease lines immediately. But on a tall ship with a skeleton professional crew and students or guests whose safety must be maintained, the loads are heavy, and the rig by comparison is extraordinarily complex and inefficient to handle. Reefing or dousing all of those sails would take an extremely long time -- far too long if the tall ship has already been hit by an unexpected microburst. In general, a tall ship could probably work only a few sails at a time especially in severe conditions.

There may be other differences in terms of the relative strength and margins of the rigging, windage, speed of maneuvering and ability to maneuver to reduce loads, difficulty of tacking square riggers especially in heavy air, etc., but someone more expert can discuss these.
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