# lee pod volume

how big should the lee pod be?

on madness it's


so if it was a square box `2.8*0.9*0.55 = 1.38` but it's curved, but it should be more than half of that, which is 622 litres.

total displacement is 1056 kg. so lets say volume is between 60% and 140% displacement.

the clearance is 0.42, and it sticks out 0.9, so it hits the surface at 25
degrees of heel. As the ama comes up, the righting moment reduces, but there is still 90% of the righting moment from the ama.

in this video we see the leepod skimming the surface

https://youtu.be/PWXbyVw95UQ?t=164


I measured 21 degrees. it's hitting a wave top, not plowing through.

so the righting moment is maximum at a few degrees when the ama first leaves the water

the ama has very little draft, so it's less than 5 degrees


then goes down slightly but only to 90% of maximum, then stops going down as much... the ama is much further out than the pod, so even if the counter weight is the whole boat the level isn't very long. I'm not sure where the center of gravity is.

> Even without resorting to exotic materials, a very light hull is the result. Slung from my digital scale, the stripped main hull is right at _222 kg_. The outrigger, crossbeams, rig, and outboard account for another _222 kg_ .

> With sails, 4hp outboard, and basic cruising gear aboard, Madness weighs about _622 kg_, and compares directly with a Farrier F-24 in terms of SA/D---at a fraction of the cost and building complexity.

(my metric conversions) that number is 400kg lighter than the design displacement.

https://www.clcboats.com/shop/boats/wooden-sailboat-kits/proa/madness-31-foot-pacific-proa.html

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havaya 25 is 7.5 m long, looks like a large leepod. at least 3 meters.


https://youtu.be/4tjPg2G0eDs?t=251

it touches down at 18 degrees


volume is `1*((0.25+0.37)/2)*2.4 = 0.774` that's less than the displacement.
but also, since the hull sides are 60 degrees, it's fully immersed when the sides of the hull touches, which is 73 degrees.


at that level of heel it's still got 29.2 % of the ama's righting moment.