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Q3. A. With reference to the underwater surface of a ship’s hull; i. Describe a hull plate roughness analyser system;

ii. State the significance of the roughness profile and compare the typical roughness values for a new ship and a ship eight years old;

B. Which reference to the application of self-polishing paint in dry dock - i. Describe the plate preparation necessary;

ii. State the defects that may occur in the paint coating if it is not correctly applied.

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

Q7. With respect to trim and stability, describe the following - A. Effects on centre of gravity of slack tanks; B. Effect on stability of ice formation on superstructure; C. Effects of wind and waves on ship’s stability; D. Effect of water absorption by deck cargo and retention of water on deck.

Q4. A. Explain the causes of the formation of mill scale on steel plate. B. Describe the preparation necessary before the application of conventional paints to the underwater surface of the hull; C. Describe a coating scheme for the underwater hull using conventional paints

Q5. A palm of the rudder of a vessel requires extensive welding repairs and as a Chief Engineer you are requested to supervise –

A. Suggest a suitable type of welding process;

B. State with reasons FOUR common welding defects that can occur there;

C. State what tests may be carried out before returning the rudder to service.

Q6. A. Explain the term angle of loll and state what, if any dangers it poses to a vessel. B. A ship whose length is 110 m has MCTI cm 55 tonne m: TCP9; LCF 1.5 m forward of midships and floats at draughts of 4.20m forward and 4.45m aft. Calculate the new draughts after the following masses have been added, 20 tonne 40 m aft of midships; 50 tonne 23 m aft of midships; 30 tonne 02 m aft of midships; 70 tonne 06 m forward of midships; 15 tonne 30 m forward of midships;

Q7. A. Explain what is meant by ‘assigned summer free board’. B. A ship 120m long has draughts of 6.6m forward and 6.9 aft. The TPC is 20, MCTI cm 101 tonne m and the centre of flotation 3.5m aft of midships. Calculate the maximum position aft at which 240 tonne may be added so that the after draught does not exceed 7.2m

Q1. A. Explain the purpose of the rudder carrier and pintles.

B. The speed of a ship is increased to 18% above normal for 7.5 hours, and then reduced to 9% below normal for 10 hours. The speed is then reduced for the remainder of the day so that the consumption for the day is the normal amount. Find the percentage difference between the distance travelled in that day and the normal distance travelled per day.

Q7. A. Describe the effect of cavitation’s on the propeller blades.

B. A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power.

Q8. A. Describe the stability requirements of a ship for dry-docking.

B. A ship 130m long displaces 14000 tonne when floating at draughts of 7.5m forward and 8.10m aft. GML – 125m, TPC – 18,LCF-3m aft of midships. Calculate the final draughts when a mass of 180 tonne lying 40m aft of midships is removed from the ship.