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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.

Q2. If a ship is seriously damaged under water in way of a large fuel side bunker tank what is the immediate effect and what may ultimately happen? What features in the ship would enhance safety?

Q1. A. Sketch a transverse section through the hold space of a container ship hull;

B. Referring to the sketch in (A) describe how adequate structural strength is built into the hull.

Q4. Discuss the importance of the following to be examined for meeting EEDI limitations: A. Slimmer vessels with lower block coefficients; B. Long-Stroke engines; C. Low revolution large diameter propellers.

Q1. A. Sketch the cross-section of a bulk carrier with either deep or shallow double bottom showing the type of framing used;

B. Describe the corrosion problems experienced with ballast tanks;

C. state how such tanks are protected against extensive corrosion.

Q6. A. Explain how to distinguish between list and loll and describe how to return the ship to the upright in each case. (6)

B. A propeller has a pitch ratio of 0.95. When turning at 120 rev/min the real slip is 30%, the wake fraction 0.28 and the ship speed 16 knots. The thrust is found to be 400 KN, the torque 270 KN-m and the QPC 0.67. Calculate: (10)

i. The propeller diameter.

ii. The shaft power.

iii the propeller efficiency.

iv. The thrust deduction factor.

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.

Q8. A. Why is it important in a tender ship to keep the double bottom tanks pressed up?

B. A ship of 6000 tonne displacement has a wetted surface area of 2500 m2 and a speed of 15 knots.

(i) Calculate the corresponding speed and wetted surface area of as similar ship of 2000 tonne displacement.

(ii) If the ship resistance is of the form R=0.45 S V1.83 N; find the resistance of the 6000 tonne Ship.

Q9. A. Explain the effects on stability when a tank is partially filled with liquid. (6)

B) A box barge 45 m long and 15 m wide floats at a level keel draught of 2 m in sea water, the load being uniformly distributed over the full length. Two masses, each of 30 tonne, are loaded at 10 m from each end and 50 tonne is evenly distributed between them. Sketch the shear force diagram and give the maximum shear force. (10)

Q10.  The breadth of the upper edge of a deep tank bulkhead is 12 metres. The vertical heights of the bulkhead at equidistant intervals across it are 0, 3, 5, 6, 5, 3 and 0 metres respectively. Find the depth of the centre of pressure below the waterline when the tank is filled to a head of 2 metres above the top of the tank.