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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.

Q2. A. Describe the arrangement made in a main structural bulkhead for a watertight door aperture; B. Explain a procedure for ensuring that sliding watertight doors are operated safely. C. Differentiate between the categories of watertight door and state the regulation pertaining each type.

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: 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.

Q4: With regard to the carriage of crude oil and its associated products: i. Sketch and describe the operation of an explosimeter suitable for testing pump rooms or tanks; ii. State why false readings are likely to be given by the explosimeter. iii. State the publication that gives guidance on safety.

Q6. Explain why the bilging of empty double-bottom or deep tanks below the waterline leads to an increase in GM. B. A ship of 10,000 tonnes displacement has GM=0.5 metres. The period of roll in still water is 20 seconds. Find the new period of roll if a mass of 50 tonnes is discharged from a position 14 metres above the centre of gravity.

Q7. A. Describe the effect of Cavitation on; The thrust and torque; The propeller blades B.A ship 120m long displaces 10500 tonne and has a wetted surface area of 3000m2. At 15 knots the shaft power is 4100KW, propulsive coefficient 0.6 and 55% of the thrust is available to overcome frictional resistance; calculate the shaft power required for a similar ship 140m long at the corresponding speed.   = 0.42 and n = 1.825

Q8. A. Describe the ways in which an unstable ship can be made stable. B. When a mass of 25 tonnes is shifted 15m transversely across the deck of a ship of 8,000 tonnes displacement, it causes a deflection of 20cms in a plumb line 4m long. If the KM=7 m, calculate the KG

Q10. A. Explain the considerations which govern the size and shape of a rudder. 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: Fa=577 Av2 sin  N, Allow 20% for the race effect.

Q10. A. List the components of residuary resistance. B. The following data are available for a twin-screw vessel:

Calculate the service speed if the brake power for each engine is 3500Kw. The transmission is 3% and the allowances for weather and appendages 30%.