Page 227 - statbility for masters and mates

(b) Vessel's condition after bilging. Find the New Draft
Lost buoyancy 4 8 3 1:025 tonnes TPCSW WPA 36 8
Bilging and permeability 215
97:56 97:56 Increase in draft Lost buoyancy
33:3 cm or 0.33 m
TPC
4 8 3 1:025
100 cm 36 8 1:025
It should be noted that the increase in draft can also be found as follows: Increase in draft Volume of lost buoyancy 4 8 3
Area of intact water-plane 1=3 metres.
Original draft 3:000 m draft d1 New draft 3:333 m draft d2
(c) Find the New GM
KB d2 1:67m 2
36 8
BM I/V (Note: `I' represents the second moment
of the intact water-plane about the centre line)
L l B3 36 83
12 V 12 40 8 3
1:60 m
1:67 m
3:27 m
When solving problems involving bilging and permeability it is suggested that:
1 Make a sketch from given information.
2 Calculate mean bodily sinkage using w and TPC.
3 Calculate change of trim using GML or BML.
4 Collect calculated data to evaluate the ®nal requested end drafts.
BM2 KB2
KM2 KG
2:28 m as before bilging occurred 0:99 m
Final GM2
GM2 is ve so vessel is in stable equilibrium.
Summary