Page 170 - statbility for masters and mates

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Ship Stability for Masters and Mates
Find the amount of cargo which must be discharged from Nos. 1 and 4 holds if the ship is to sail on an even keel.
A ship is 150 m long, displacement 12 000 tonnes, and is ¯oating at drafts of 7m F and 8m A. The ship is to enter port from an anchorage with a maximum draft of 7.6 m. Find the minimum amount of cargo to discharge from a hold whose centre of gravity is 50 m aft of the centre of ¯otation (which is amidships), TPC 15 tonnes, and MCT 1 cm 300 tonnes m. A ship 150m 20m ¯oats on an even keel at 10m draft and has a block coef®cient of ®neness 0.8 and LGM of 200 metres. If 250 tonnes of cargo is discharged from a position 32 m from the centre of ¯otation, ®nd the resulting change of trim.
A ship is ¯oating in salt water at drafts of 6.7 m F and 7.3 m A. MCT 1 cm 250 tonnes m. TPC 10 tonnes. Length of ship 120 metres. The centre of ¯otation is amidships. 220 tonnes of cargo is then discharged from a position 24 m forward of the centre of ¯otation. Find the weight of cargo which must now be shifted from 5 m aft of the centre of ¯otation to a position 20 m forward of the centre of ¯otation, to bring the draft aft to 7 metres. Find also the ®nal draft forward.
A ship ¯oats in salt water on an even keel displacing 6200 tonnes. KG 5.5 m, KM 6.3 m, and there is 500 tonnes of cargo yet to load. Space is available in No. 1 `tween deck (KG 7.6 m, centre of gravity 40 m forward of the centre of ¯otation) and in No. 4 lower hold (KG 5.5 m, centre of gravity 30 m aft of the centre of ¯otation). Find how much cargo to load in each space to complete loading trimmed 0.6 m by the stern, and ®nd also the ®nal GM. MCT 1 cm 200 tonnes m.
A ship, ¯oating at drafts of 7.7 m F and 7.9 m. A sustains damage in an end-on collision and has to lift the bow to reduce the draft forward to 6.7 m. The ship is about to enter a port in which the maximum permissible draft is 8.3 m. To do this it is decided to discharge cargo from No. 1 hold (centre of gravity 75 m forward of amidships) and No. 4 hold (centre of gravity 45 m aft of amidships). MCT 1 cm 200 tonnes m, TPC 15 tonnes. Centre of ¯otation is amidships. Find the minimum amount of cargo to discharge from each hold.
A ship 100m long has centre of ¯otation 3m aft of amidships and is ¯oating at drafts 3.2m F and 4.4m A. TPC 10 tonnes. MCT 1cm 150 tonnes m. 30 tonnes of cargo is then discharged from 20 m forward of amidships and 40 tonnes is discharged from 12 m aft of amidships. Find the ®nal drafts.
A ship 84 metres long is ¯oating on an even keel at a draft of 5.5 metres. 45 tonnes of cargo is then loaded in a position 30 m aft of amidships. The centre of ¯otation is 1m aft of amidships. TPC 15 tonnes. MCT 1 cm 200 tonnes m. Find the ®nal drafts.
A ship arrives in port with drafts 6.8 m. F and 7.2 m A. 500 tonnes of cargo is then discharged from each of 4 holds.