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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. With reference to the prevention of hull corrosion discusses:

A. Surface preparation and painting of new ship plates.

B. Design of the ships structure and its maintenance. C. Catholic protection by sacrificial anodes, of the internal and external areas of the ship.

Q1. A. Describe the preparation necessary before the application (in dry dock) of sophisticated or approved long life coating to the underwater surface of the hull;

B. State the significance of the roughness profile.

C. List the different sophisticated costing which are available.

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: With reference to fatigue of engineering components explain the influence of stress level and cyclical frequency on expected operating life;

A. Explain the influence of material defects on the safe operating life of an engineering component;

B. State the factors which influence the possibility of fatigue cracking of a bed-plate transverse girder and explain how the risk of such cracking can be minimized.

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

Q6. A. What factors influence the frictional resistance of a ship and what formula is used to calculate the resistance? B. A ship of 12000 tonne displacement has a rudder 15m2 in area, whose centre is 5m below the waterline.  The metacentric height of the ship is 0.3m and the centre of buoyancy is 3.3m below the waterline.  When travelling at 20 knots the rudder is turned through 30 .  Find the initial angle of heel if the force Fn perpendicular to the plane of the rudder is given by:  Fn=577 Av2 sin  N, Allow 20% for the race effect.

Q10. A. List the precautions necessary before an inclining experiment is carried out.

B. A box shaped vessel, 50 metres long × 10 metres wide, floats in salt water on an even keel at a draft of 4 metres. A centre line longitudinal watertight bulkhead extends from end to end and for the full depth of the vessel. A compartment amidships on the starboard side is 15 metres long and contains cargo with permeability 30%. Calculate the list if this compartment is bilged. KG = 3 metres.

Q8. A. Define longitudinal centre of gravity (LCG) and longitudinal centre of buoyancy (LCB).

B. A ship 120m long floats has draughts of 5.50m forward and 5.80m aft; MCT1 cm 80 tonne m, TPC 13, LCF 2.5m forward of midships. Calculate the new draughts when a mass of 110 tonne is added 24m aft of midships.