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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.

Q5. With respect to Induced Vibrations in a ships hull:

A. State FOUR sources of excitation that may induce vibration into the main hull girder;

B. Suggest methods for reducing the vibration levels induced by EACH of the exciting forces in A.

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.

Q5. A ballast tank is one third full when additional ballast is added until it is two thirds full. The increased amount of liquid in the tank will have the greatest influence on the. Free surface effect; Transverse stability; Virtual rise in the center of gravity; Value of the moment to trim 1 inch (MTI). Give a detailed explanation stating why the other options were not considered.

Q6. A ship 90 m long displaces 5200 tonne and floats at draughts of 4.95m forward and 5.35 m aft when in sea water of 1023 kg/m3. The water plane 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

Q10. The daily fuel consumption of a ship at 17 knots is 42 tonne. Calculate the speed of the ship if the consumption is reduced to 28 tonne per day, and the specific consumption at the reduced speed is 18% more than at 17 knots.

Q8. A ship 160m long and 8700 tonne displacement floats at a waterline with

While floating at this waterline, the ship develops a list of 10° due to instability. Calculate the negative metacentric height when the vessel is upright in this condition

Q9. A. Describe briefly the inclining experiment and explain how the results are used. B. A ship of 8500 tonne displacement has a double bottom tank 11m wide extending for the full breadth of the ship, having a free surface of seawater. If the apparent loss in metacentric height due to slack water is 14cm, find the length of the tank.

Q10. The end bulkhead of the wing tank of an oil tanker has the following widths at 3m intervals commencing at the deck: 6.0, 6.0, 5.3, 3.6 and 0.6 m. Calculate the load on the bulkhead and the position of the centre of pressure if the tank is full of oil rd 0.8.