# Freeboard calculation according to ICLL

Discussion in 'Boat Design' started by e.m.milad, Jan 31, 2017.

1. Joined: Jun 2015
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Location: Gulf

Hi every body
I am trying to calculate freeboard of a vessel
in my calculation I found (freshwater allowance) less than (summer freeboard - tropical freeboard)
is it possible?
I mean this means ship allows to sink more in tropical zone more than in fresh water!!!
is it possible?
where is my problem??
is the model and TPC or displacement is wrong?

2. Joined: Oct 2008
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Location: Japan

I think you need to supply more information that that. As there is insufficient information to say what/where/why....

3. Joined: Jun 2015
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Location: Gulf

Well I think because water density of oceans is about 1.020 to 1.029 then the maximum tropical draft of one specific ship (regardless of ship type) shall always be less than maximum freshwater draft.
I want to know if (by some reasons I do not know why) in freeboard calculation we reach opposite results what should we do?

4. Joined: Apr 2015
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Location: Berlin, Germany

### HeimfriedSenior Member

The greater the freeboard the lesser the draft. Did you mix it up?

E. g.: The deckline shall be z(deck) above the keelline (z(keel) = 0) . The tropical fresh water draft is z(TF). Then the freeboard TF is z(deck) - z(TF).

The winter north atlantic draft z(WNA) is lesser then z(TF), therefore the freeboard WNA is greater: freeboard WNA = z(deck) - z(WNA).

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