Page 162 - statbility for masters and mates

150 Ship Stability for Masters and Mates
So,
But,
Equate (I) and (II)
or
where
l Changeoftrim w L TPC
Changeoftrim w L I TPC l
Change of trim w d II MCT 1 cm
; w d w L MCT1cm TPC l
d L MCT 1 cm l TPC
d the distance forward of the centre of ¯otation to load a weight to keep the draft aft constant,
L the ship's length, LBP and
l the distance of the centre of ¯otation to the stern.
Example
A box-shaped vessel 60 m long, 10 m beam, and 6 m deep, is ¯oating in salt water at drafts 4 m F and 4.4 m A. Find how far forward of amidships a weight of 30 tonnes must be loaded if the draft aft is to remain at 4.4 m.
TPCSW WPA 97:56
60 10 97:56
TPCSW 6:15 tonnes W L B d rSW tonnes
60 10 4:2 1:025 W 2583 tonnes
BML L2 12d
60 60 12 4:2
BML 71:42 metres
MCT1cm'W BML becauseGML 'BML 100L