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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.

Q2. With reference to dry docking, define the responsibilities of the Second Engineer: (16)

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.

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. With reference to Roll-on Roll-off ferries –

A. Describe the problem of free surface effect;

B. Explain how it is intended that water should be cleared from car or cargo decks;

C. Describe possible methods for improving the stability and survivability of these vessels.

Q6.A. What do you understand by reserve buoyancy what happen if the lost buoyancy is greater than the reserve buoyancy? (6)

B. A forward deep tank 12 m long extends from a longitudinal bulkhead to the ship’s side. The widths of the tank surface measured from the longitudinal bulkhead at regular intervals are 10, 9, 7, 4 and 1 m. Calculate the second moment of area of the tank surface about a longitudinal axis passing through its centroid. (10)

Q7. 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 ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships.  (10)

The following items are then added:

Cargo    10000 tonne      LCG 3.0 m          forward of midships

Fuel      1500 tonne        LCG 2.0 m          aft of midships

Water    400 tonne          LCG 8.0 m          aft of midships

Stores   100 tonne          LCG 10.0m         forward of midships

Using the following hydrostatic data, calculate the final draughts:

Draught (m) --- Displacement (t) --- MCTI cm (tm) --- LCB from midships (m) --- LCF from midships (m)
8.50 ---------- 16650 -------------- 183 ------------ 1.94 F ------------------ 1.20A
8.00 ---------- 15350 -------------- 175 ------------ 2.10 F ------------------ 0.60F

Q8. A. Explain how the distribution of masses affects rolling and pitching

B.A ship turns is a circle of radius 100 metres at a speed of 15 knots. The GM is 2/3 metres and BG is 1 metre. If g = 981 cm/sec2 and 1 knot is equal to 1.8532 Km/hour, find the heel due to turning.

Q7. A. Describe the effect of cavitation’s on the propeller blades.

B. A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power.

Q8. A. Describe the stability requirements of a ship for dry-docking.

B. A ship 130m long displaces 14000 tonne when floating at draughts of 7.5m forward and 8.10m aft. GML – 125m, TPC – 18,LCF-3m aft of midships. Calculate the final draughts when a mass of 180 tonne lying 40m aft of midships is removed from the ship.