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Q1. During routine soundings, it is found that leakage into a cofferdam is occurring from an adjacent cargo oil deep tank. The procedure you will follow to ascertain the cause of the leakage. If the leakage persists, discuss EACH of the following options as a possible remedy: Leave the cofferdam to flood with oil; Flood the cofferdam with sea water; Seal the cofferdam and pressurize with air Pump the leakage to bunker tanks

Q3: With reference to dry docking, define the responsibility of the second engineer;

A. Prior to docking;

B. Whilst the vessel is in dry dock;

C. Prior to flooding and leaving the dock.

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.

8. When a ship is 800 nautical miles from port its speed is reduced by 20%, thereby reducing the daily fuel consumption by 42 tonne and arriving in port with 50 tonne on board. If the fuel consumption in t/h is given by the expression (0.136+0.001 V3) where V is the speed in knots, estimate:(i) The reduced consumption per day; (ii) The amount of fuel on board when the speed was reduced(iii) The percentage decrease in consumption for the latter part of the voyage;(iv) The percentage increases in time for this latter period.

Q8. A. Describe the fundamental principle of a propeller. B.A propeller 6m diameter has a pitch ratio of 0.9, BAR 0.48 and, when turning at 110 rev/min, has a real slip of 25% and wake faction 0.30. If the propeller delivers a thrust of 300 KN and the propeller efficiency is 0.65. Calculate - i Blade area; ii Ship speed; iii. Thrust power; iv Shaft power v. Torque

Q9. A. Describe measures which may be taken to improve the stability or trim of a damaged ships.

B. A ship 85m long displaces 8100 tonne when floating in seawater at draughts of 5.25m forward and 5.55m aft. TPC 9.0, GML 96m, LCF 2m aft of midships. It is decided to introduce water ballast to completely submerge the propeller and a draught aft of 5.85m is required. A ballast tank 33m aft of midships is available. Find the least amount of water required and the final draught forward.

Q6. A. Describe how the distribution of mass within the ship affects the rolling period 2016/SR09

B. The righting moments of a ship at angles of heel of 0, 15°, 30°, 45°, and 60° are 0, 1690, 5430, 9360 and 9140 k/Nm respectively. Calculate the dynamical stability at 60°.

Q7. A. Explain how to distinguish between list and loll and describe how to return the ship to the upright in each case. B. A ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships.  The following items are then added:

Using the following hydrostatic data, calculate the fine draughts: