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Old 08-16-2009, 06:53 AM
sighmoon sighmoon is offline
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IRC rating and performance

I'm looking at two boats, one is a radical racer with a big lead bulb at the bottom of a high aspect keel, and a wide, flared hull. It looks like it ought to go like a rocket. The other is a more traditional design, with around the same displacement, same length, and a less deep, cast iron keel, and a slightly smaller rig.

I would have thought the former would be significantly faster, but in fact, according to its IRC rating, it is only about 3% faster. Is the IRC rating an unrealistic guide to performance, or do all the radical features make little difference in practice?
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Old 08-16-2009, 09:53 AM
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marshmat marshmat is offline
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If you ask me, an IRC (or any other) rating is only relevant if you actually plan to do some serious racing.

If you're interested in a good all-round boat for cruising and maybe a bit of friendly club racing, I wouldn't even bother with the boat's rating. There are many other factors that are far more important if you're actually cruising the boat.

A speed difference of 3% is 158 feet per mile- not much of a gap. Odds are your first boat is designed to cheat the rule to some extent, thus earning a rating that makes it appear slower than it really is. Of course, just because something looks fast, doesn't mean that it is fast- or that it will be able to keep up that pace in rougher conditions.
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