[CLOH-News] Can you tell a story or write a lesson about boat wakes?

[Mark Rauterkus]

Hi,

Looking for someone to take this a a base for an article and run with it. I
think this could make interesting reading for a swimmer.


Mark R

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Why aren't ski boats designed like sailboats. It's rare to see a wake
behind a sailboat even with the boat sailing at a speed of 15 to 20 knots.
Could one develop a displacement ski boat that did 36 mph, as it would be
great to ski behind a boat without any wake.



The Horse Power (HP) required to push a true displacement hull to a
particular speed climbs nonlinearly beyond the particular hull's "hull
speed." That hull speed is an effective upper limit on the speed of the
hull, and is only a factor of the waterline length. A good approximation is
1.34 X sqrt(LWL) = hull speed in knots.

For 35 knots, that means LWL needs to be 681 feet. A 25 foot boat has a
theoretical hull speed of 6.7 knots.