Primbee clip from last week

Thought Id share my latest attempt at editing. A clip from Primbee last week.

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tazmania said..
it's only what, knee deep?

About 1/2 that at low tide. It's extremely shallow. You can see the depth at end of the video.

You get some idea when sailing by looking at the chop. At 1.05 on the video you can sort of see a longer wavelength and a bit more height to the chop. That's about knee deep. At 2.26 the waves have bunched up and gotten smaller. That's 1/2 knee deep. It's a bit of guess work, weed also has an effect. Also if you note that the board is starting to feel really slippery, and your speed is rising due to unknown causes, it's probably the ground effect kicking in.

I've just googled "planing hulls in shallow water" The best I've come up with is this graph
http://hydrocompinc.com/blog/time-trial-racing-–-deep-water-versus-shallow-water


At low non-planing speed the shallow water curves are above the deep water curve, but once the model starts planing the shallow water has less drag. You probably should compare the curves by looking along horizontal lines. Your speed increases until the forward lift of the sail equals the drag of the hull. So all sails being equal, for 20 units of sail lift the speed in flat shallow water vs flat deep water would be up from 2.5 to 3.4 units. ( But it's not that simple because as you go faster you'll lose apparent wind and sail lift decreases, so somewhere in between.)

Great video Stu. When did you shave?

You out over the weekend? Sunday and Monday look like fun

Thanks guys. Yeah I'm working Sunday but after a lucky break I'm now in the clear for Monday Still considering a sickie Sunday though

Good sailing love the G'n'F'n'R's!