Overpowered

Twister_Ken

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Re: Hull speed?

Mike, probably it was planing.

Possibly there was a big sea running, and you managed to catch a wave right? Planing or surfing can be hilarious for the rest of the crew, but pity the poor trimmers. Every time the boat surfs, the apparent goes forward (Trim!). Then when it drops off the plane the apparent goes aft (Give 'er some sheet you dozy pillock!)
 

brianhumber

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Assuming you started in G&T conditions-
If you hav'nt got wind instruments, look at the sea state. If you see white crests or breaking crests when none before - the winds got up.
If you have, then put the true wind speed alarm on, when it goes off - the winds got up.
In both cases time get the kite down and when cruising it's the same as putting a reef in, do it on the first sign.
 

Miker

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Re: Hull speed?

Sounds like it from your description. It was fun while it lasted! The boat has a broad flat stern which, perhaps, helps it to surf on waves.
 
G

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Re: Hull speed?

Downwind speed! That's what you paid all that money for!
 

quaelgeist2

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Hull speed

....mmmh traditionally, yes - leaving aside the surfing down waves for a moment.

An increasing number of boat designs, e.g. First 300, some Jantar,... have a hull design that aloows for real planing. In the case of the First 300 even without a spi.
Flat bottoms and broad/flat sterns are a pre-requisite, so are slim fin keels with a heavy bulb at the end.

The overpowering then becomes a pure question of skills an stamina of the crew.

Never mind the VO60 or similar designs who have pushed the envelope even further - try the usual formula and then check out the average speeds

regards
chris
 

Aja

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Re: Hull speed?

best guess is the square root of waterline length times 1.4 (sometimes quoted as 1.5)
 

claymore

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Re: Hull speed

Quite right of course - I think when I made my comments I was doing a bit of blinkered thinking around the theme of traditional hull shapes. I suppose though that the same rules of dumping power must apply even to the Volvo racers in that, as you suggest, when in conditions where optimum velocity can be attained, they need to think about preserving the boat and crew?
 
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