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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.

Q4. With reference to Underwater Inspection in lieu of Dry  docking (UWILD)

A. Explain in detail, how an underwater survey is carried out;

B. State the requirements to be fulfilled before an underwater survey is acceptable to the survey authority.

C. Construct a list of the items in order of importance that the underwater survey authority should include.

Q5. Regarding the carriage of crude oil and its associated products:

a) (i) State the dangers involved.

(ii) State what publications give guidance on safety.

b) Sketch and describe the operation of an explosimeter suitable for testing pump rooms or tanks.

c) Define the terms lower and upper flammable limits Illustrating your answer by means rough sketch of a hydrocarbon vapour oxygen graph.

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.

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

Q8. a) Describe the process of correcting a negative GM. (6)

B. A ship 120 m long displaces 10500 tonne and has a wetted surface area of 3000 m2. At 15 knots the shaft power is 4100 kW, propulsive coefficient 0.6 and 55% of the thrust is available to overcome frictional resistance; calculate the shaft power required for a similar ship 140 m long at the corresponding speed.  = 0.42 and n = 1.825  (10)

Q9. a) Explain why the rudder angle does not normally exceed 35°. (6)

b) A ship of 12000 tonne displacement has a rudder 15m2 in area, whose centre is 5 m 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. (10)

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%.