DieselShip's Online Content Library

Q1. a) State the reasons for the freeboard requirement. (6)

b) Explain the term condition of assignment and explain how these are maintained for a ship. (5)

c) What is the difference between a Type “A” and a Type “B” ship. (5)

Q2. a) Sketch the cross-section of a bulk carrier with either deep or shallow double bottom showing the type of framing used. (8)

b) i) Describe the corrosion problems experienced with ballast tanks. (4)

ii) State how such tanks are protected against extensive corrosion. (4)

Q3. a) With the aid of a sketch describe the method of attachment for a bilge keel and hence explain what protection is made to reduce the possibility of the shell being punctured in the event of damage to the keel. (6)

b) State why the keel does not extend for the length of the ship. (5)

c) Evaluate the effectiveness of bilge keels for large wall sided vessels. (5)

Q4. a) Draw a simple line diagram of the bow of a ship to show the position of the following component parts of the ships anchoring system.  Hawse pipe, Cable stopper, Windlass and Cable lifter, Spurling pipe and Chain locker. (4)

b) Describe the cable stopper and state its purpose. (4)

c) Show by means of a sketch how the anchor cable is attached to the ship. (4)

d) Describe how the chain locker is drained of water, sand and mud. (4)

Q5. With reference to membrane tanks for the carriage of liquefied gas at very low temperatures.

a) Describe with a sketch one method of building up the insulation. (6)

b) State which alloy is used for the membrane and the reason. (5)

c) Explain why a secondary barrier is installed. (5)

Q6. A. Describe how the force on the ship’s bottom and the GM vary when grounding takes place. (6)

B. A ship of 8,000 tonnes displacement takes the ground on a sand bank on a falling tide at an even keel draft of 5.2 metres. KG 4.0 metres. The predicted depth of water over the sand bank at the following low water is 3.2 metres. Calculate the GM at this time assuming that the KM will then be 5.0 metres and that mean TPC is 15 tonne. (10)

Q7. A. Describe stability requirement for dry-docking. (6)

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. (10)

Q8. A. Define longitudinal centre of gravity (LCG) and longitudinal centre of buoyancy (LCB). (6)

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. (10)

Q9. A. What are the main components of ship resistance that a vessel encounters while moving through water. (6)

B. The speed of a ship is increased to 18% above normal for 7.5 hours and then reduced to 9% below normal for 10 hours. The speed is then reduced for the remainder of the day so that the consumption for the day is the normal amount. Find the percentage difference between the distance travelled in that day and the normal distance travelled per day. (10)

Q10. With reference to fixed pitch propellers:
a. Explain Propeller Slip and Propeller Thrust. (6)
b. The shaft power of a ship is 3000 kW, the ship’s speed V is 13.2 knot. Propeller RPS is 1.27. Propeller pitch is 5.5 m and the speed of advance is 11 Knots. Find:
i. Real Slip
ii. Wake fraction
iii. Propeller thrust, when its efficiency, η = 70% (10)