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Q3. a) With the aid of a sketch describe the method of attachment for a bilge keel and hence explain what protection is made to reduce the possibility of the shell being punctured in the event of damage to the keel. (6)

b) State why the keel does not extend for the length of the ship. (5)

c) Evaluate the effectiveness of bilge keels for large wall sided vessels. (5)

Q2. A. Describe the double bottom and framing arrangement used in the machinery space to cope up with the concentrated loads and vibration, together with shaft and thrust block support.

B. Give reasons for the choice of thrust block position.

Q4. Discuss the need for adequate support of engine room gantry cranes, detailing the following

(a)  Sketch section through the engine room casing showing how the crane is supported by the ship structure;

(b) State what restricts the forward and aft limits of the crane and what is fitted to prevent the crane damaging the forward and aft bulkheads or casing.

(c)  State the Second Engineer’s responsibilities for the engine room gantry crane.

Q1. With reference to membrane tanks for the carriage of liquefied gas at very low temperatures. A. Describe with a sketch one method of building up the insulation; B. State which alloy is used for the membrane and the reason; C. Describe with the aid of a sketch, how the tanks are located and supported. i) Longitudinally; ii) Transversely

Q2. State how and why the following machinery items are effected when the maximum service speed of a Vessel is consistently maintained in heavy weather.

A. Intermediate shafting,

B. Propeller shafting,

C. Shafting coupling bolts,

D. Main thrust pads.

Q6. A. Explain the purpose of non-watertight longitudinal subdivision of tanks. B. A ship 90 long displaces 5200 tonne and floats at draughts of 4.95m forward a nd 5.35 m aft when in sea water of 1023 kg/m3. The waterplane area is 1100m2, GML 95m, LCB 0.6m forward of midships and LCF 2.2m aft of midships. Calculate the new draughts when the vessel moves into fresh water of 1002 kg/m3

Q9. (a) Describe how thrust power is determined. (6)

(b) The following information relates to a model propeller of 400mm pitch:

(i) Plot curves of thrust and torque against rev/min

(ii) When the speed of advance of the model is 150 m / min and slip 0.20, calculate the efficiency.

Q8. A. Explain why the amplitude of ship motion should be limited B. A ship of 8100 tonne displacement floats upright in seawater. KG = 7.5m and GM = 0.45m A tank, whose centre of gravity is 0.5m above the keel and 4m from the centreline, contains 100 tonne of water ballast neglecting free face effect, calculate the angle of heel when the ballast is pumped out.

Q6. A. Describe how water tightness is maintained where bulkheads are pierced by longitudinal beams or pipes.

B. A triangular bulkhead is 7 m wide at the top and has a vertical depth of 8 m.  Calculate the load on the bulkhead and the position of centre of pressure if the bulkhead is flooded with sea water on only side:

(i) to the top edge,               (ii) with 4 m head to the top edge.

Q7. A. Distinguish between ships of Type “A” and Type “B” for the purpose of computation of free board, B. The draughts of a ship 170m long are 6.8.5 m forward and 7.50m aft MCTI cm 300 tonn m; TPC 28; LCF 3.5m forward of midships. Calculate the new draughts after the following changes in loading have taken place. 160 tonne added 63 m aft of midships; 200 tonne added 27m forward of midships; 120 tonne removed 75 m aft of midships; 70 tonne removed 16 m aft of midships