Thread: Hull speed
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Jere Lull
 
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Default Hull speed

Jim Woodward wrote:

Not quite. If you get a chance, watch carefully when a tug or pilot
boat approaches a big ship at, say, 15 knots. The tug is hurrying
along like mad, throwing a huge bow wave, while the big ship is just
gliding effortlessly through the water. When the tug gets within a ten
or twenty feet of the big ship, suddenly it, too, is gliding along
effortlessly as it has become part of the big ship's wave pattern.
Tugs have to be careful at this moment because the power required goes
down dramatically.


That's a special case! Most cruisers don't drag a boat behind them that
is bigger than they are. (but I regularly use other boats' wakes to
increase our speed when possible. Most times, I'm cursing powerboat
wakes from the wrong direction, though.)

Your dinghy may not do it, but it is possible to fool the water -- the
Kiwis tried it in the last America's Cup

As I recall, that attempt didn't work particularly well....

But our little boat with a wide flattish transom considers hull speed
(1.34 x sqrt(LWL)) a suggestion rather than the law. It seems the AC
boats and other newer sleds are more advanced that way.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
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