Ship Construction & Stability

(a) Explain in detail, how an underwater survey is carried out. (7)

(b) State the requirements to be fulfilled before an under -water survey is acceptable to the survey authority. (5)

(c) Construct a list of the items in order of importance that the underwater survey authority should include. (4)

If a ship is seriously damaged under water in way of a large fuel oil side bunker tank what is the immediate effect and what may ultimately happen? What features in the ship would enhance safety? (16)

(a) Sketch a transverse section through the hold space of a container ship hull. (8)

(b) Referring to the sketch in (a) describe how adequate structural strength is built into the hull. (8)

Discuss the importance of the following to be examined for meeting EEDI limitations: (16)

(a) Slimmer vessels with lower block coefficients

(b) Long-Stroke engines

(c) Low revolution large diameter propellers

(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.

(ii) State how such tanks are protected against extensive corrosion. (8)

(a) Explain the term angle of loll and state what, if any dangers it poses to a vessel. (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 KNm and the QPC 0.67.

Calculate: (10)

(i) Propeller diameter

(ii) Shaft Power

(iii) Propeller efficiency

(iv) Thrust Deduction Factor

(a) What factors influence the frictional resistance of a ship and what formula is used to calculate this resistance. (6)

(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 sinα N

Allow 20% for the race effect. (10)

(a) Why is it important in a tender ship to keep the double bottom tanks pressed up. (6)

(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 a similar ship of 2000 tonne displacement.

(ii) If the skin resistance is of the form R=0.45 SV^1.83 N ; find the resistance of the 6000 tonne ship (10)

(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)

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 center of pressure below the waterline when the tank is filled to a head of 2 metres above the top of the tank. (16)

(a) State the reasons for the freeboard requirement. (4)

(b) Explain the term condition of assignment. Explain how these are maintained for a ship. (4)

(c) Using a diagram indicate the freeboard of type A, type B, type B60, and type B100 vessels. (8)

(a) Describe the double bottom and framing arrangement used in the machinery space to cope up with the concentrated loads and vibration, together with shaft and thrust block support. (10)

(b) Give reasons for the choice of thrust block position. (6)

(a) With reference to fatigue of engineering components explain the influence of stress level and cyclical frequency on expected operating life. (6)

(b) Explain the influence of material defects on the safe operating life of an engineering component. (4)

(c) 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. (6)

With reference to a periodically unattended machinery space of a dry cargo vessel discuss the requirements for:

(a) Protection against flooding. (8)

(b) Control of propulsion machinery from the navigating bridge. (8)

(a) Describe, where on the hull plating would the following tests be carried out on the ships' hulls during drydock. (8)

(i) Hammer;

(ii) Hose

(b) Briefly identify which parts of the external plating of ships' hulls requires the closest attention. (8)

(a) Explain what is meant by floodable length. (6)

(b) (i) Construct a graph from the following information:

(ii) From this graph find the TPC's at draft of 3.2m, 3.7m, and 4.3m.

(iii) If the ship is floating at a mean draft of 4m, and then loads 50 tonnes of cargo, 10 tonnes of fresh water, and 25 tonnes of bunkers, whilst 45 tonnes of ballast are discharged, find the final mean draft. (10)

(a) Describe how bulkheads are tested. (6)

(b) A double bottom tank containing seawater is 6m long, 12m wide and 1m deep. The inlet pipe from the pump has its centre 75mm above the outer bottom. The pump has a pressure of 70kN/m² and is left running indefinitely, Calculate the load on the tank top: (10)

(i) if there is no outlet

(ii) if the overflow pipe extends 5 m above the tank top.

(a) Define coefficient of fineness of waterplane area, block coefficient and midship coefficient. (6)

(b) A box shaped vessel has length, 100 m and breadth 12 m and floats at a range of drafts from 1m to 10m. Produce curves of KB, BM and KM. (10)

(a) Explain the concept of dynamical stability. (6)

(b) A ship of 5000 tonne displacement has three rectangular double bottom tanks; A 12m long and 16m wide; B 14m long and 15m wide; C 14m long and 16m wide.

Calculate the free surface effect for any one tank and state in which order the tanks should be filled when making use of them for stability correction. (10)

A ship 120m long displaces 12000 tonne. The following data are available from trial results:

(a) Draw the curve of Admiralty Coefficients on a base of speed

(b) Estimate the shaft power required for a similar ship 140m long at 14 knots. (16)

(a) With reference to the underwater surface of a ship's hull

(i) Describe a hull plate roughness analyser system.

(ii) State the significance of the roughness profile and compare the typical roughness values for a new ship and a ship eight years old. (8)

(b) Which reference to the application of self-polishing paint in dry dock

(i) Describe the plate preparation necessary. (8)

(ii) State the defects that may occur in the if it is not correctly applied.

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

(a) Describe with the aid of a sketch, ONE method of building up the insulation: (6)

(b) State with reasons the alloy, which is used for the membrane. (4)

(c) Describe with the aid of a sketch, how the tanks are located and supported. (6)

(i) Longitudinally

(ii) Transversely

State FOUR terms used to describe the conditions that relate to the distortion of a ship's hull undergoes in heavy seas, stating in EACH case the type of stresses involved and where the stresses occur. (16)

With respect to trim and stability, describe the following:

(a) Effects on centre of gravity of slack tanks. (4)

(b) Effect on stability of ice formation on superstructure. (4)

(c) Effects of wind and waves on ship's stability. (4)

(d) Effect of water absorption by deck cargo and retention of water on deck. (4)

With reference to the prevention of hull corrosion discuss:

(a) Surface preparation and painting of new ship plates. (6)

(b) Design of the ships structure and its maintenance. (5)

(c) Cathodic protection by sacrificial anodes, of the internal and external areas of the ship. (5)

(a) Describe how the distribution of mass within the ship affects the rolling period. (6)

(b) The righting moments of a ship at angles of heel of 0, 15°, 30°, 45°, and 60° are 0, 1690, 5430, 9360 and 9140 kN-m respectively. Calculate the dynamical stability at 60°. (10)

(a) Describe briefly the significance of the factor of subdivision. (6)

(b) A ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships. The following items are then added: (10)

Cargo 10000 tonne LCG 3.0m forward of midships

Fuel 1500 tonne LCG 2.0 m aft of midships

Water 400 tonne LCG 8.0m aft of midships

Stores 100 tonnes LCG 10.0m forward of midships

Using the following hydrostatic data, calculate the final draughts:

(a) Explain the effect of trim on tank soundings. (6)

(b) A ship of 6600 tonne displacement has KG 3.6m and KM 4.3m. A mass of 50 tonne is now lifted from the quay by one of the ship's derricks whose head is 18 m above the keel. The ship heels to a maximum of 9.5° while the mass is being transferred. Calculate the outreach of the derrick from the ship's centreline. (10)

(a) Explain the effect on GM during the filling of a double–bottom tank (6)

(b) A ship of 8,000 tonnes displacement has KM 7.5 m, and KG 7.0 m. A double bottom tank is 12 meters long 15 meters wide and 1 meter deep. The tank is divided longitudinally at the centre line and both sides are full of salt water. Calculate the list if one side is pumped on until it is half empty. (10)

A ship of 9,900 tonnes displacement has KM = 7.3 m and KG = 6.4 m, she has yet to load two 50 tonne lifts with her own gear and the first lift is to be placed on deck on the inshore side (KG 9 m and center of gravity 6m out from the center line). When the derrick plumbs the quay its head is 15m above the keel an 12m out from the center line.

Calculate the maximum list during operation. (16)

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

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

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

Describe the process and preparation as per the classification society requirements for in-water survey of the underwater structure of a very large vessel.

Sketch and describe the construction of a bulbous bow. Why is such an arrangement fitted on a merchant ship?

With reference to the vessel hull panting and pounding

(a) Explain the causes and effects of panting and pounding, indicating the affected areas. (5)

(b) Describe the constructional details designed to resist panting and pounding. (5)

Describe the relationship between frictional resistance and

(a) Ship speed

(b) The wetted surface area

(c) The surface roughness

(d) The length of the vessel.

(a) Describe how the distribution of mass within the ship affects the rolling period. (6)

(b) The righting moments of a ship at angles of heel of 0, 150, 300, 450 and 600 are 0, 1690, 5430, 9360 and 9140 kNm respectively. Calculate the dynamical stability at 600. (10)

(a) Describe briefly the significance of the factor of subdivision. (6)

(b) A ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships. The following items are then added: (10)

Cargo 10000 tonne LCG 3.0m forward of midships

Fuel 1500 tonne LCG 2.0 m aft of midships

Water 400 tonne LCG 8.0m aft of midships

Stores 100 tonnes LCG 10.0m forward of midships

Using the following hydrostatic data, calculate the final draughts:

(a) Explain how the distribution of masses affects rolling and pitching. (6)

(b) A ship turns in 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. (10)

(a) Describe the effect of cavitations on the propeller blades. (6)

(b) A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75m. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power. (10)

(a) Describe the stability requirements of a ship for dry docking. (6)

(b) A ship 130m long displaces 14000 tonnes when floating at draughts of 7.5m forward and 8.10 m 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. (10)

(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)

(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)

(a) With the aid of a sketch describe the method of attachment for a bilge keel and hence explain why provision is made to reduce the possibility of the hull 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)

(a) Draw a simple line diagram of the bow of a ship to show the position of the following components as parts of the ships mooring 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)

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)

(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 the mean TPC is 15 tonne (10)

(a) Describe stability requirement for dry-docking. (6)

(b) A box shaped vessel, 50 metres long x 10 metres wide, floats in salt water on an even keel at a draft of 4 metres. A center 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)

(a) Define longitudinal center of gravity (LCG) and longitudinal center of buoyancy (LCB). (6)

(b) A ship 120m long floats at draughts of 5.50m forward and 5.80m aft; MCT 1 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)

(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, then reduced to 9% below normal for 10 hours. The speed is then reduced for the remainder of the day so that the consumption in 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)

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 5.5m and the speed of advance is 11 Knots. Find: (10)

(i) Real Slip

(ii) Wake fraction

(iii) Propeller thrust, when its efficiency, η = 70%

With reference to the construction of refrigerated spaces:

(a) state suitable materials that can be used for insulating refrigerated spaces. (3)

(b) state the properties that an insulating material should possess. (3)

(c) sketch a section through a wall of a cold storage space explaining how the insulation is attached to the ship's structure. (10)

With reference to dry docking, define the responsibilities of the Second Engineer and instructions to Junior Engineers:

(a) Prior to docking

(b) Whilst the vessel is in dry dock

(c) Prior to flooding and leaving the dock.

(a) Explain what is meant by "permissible length" of compartments in passenger ships.

(b) Describe how the position of bulkheads is determined.

(c) Briefly describe the significance of the factor of subdivision

Explain how the period of roll varies with:

(a) The amplitude of roll.

(b) The radius of gyration.

(c) The initial metacentric height.

(d) The location of masses in the ship

Describe the relation between frictional resistance and

(a) Ship speed

(b) The wetted area

(c) The surface roughness

(d) The length of the vessel

(a) How the distribution of mass within the ship affects the rolling period? (6)

(b) A ship of 14000 tonnes displacement is 125 m long and floats at draughts of 7.9 m forward and 8.5 m aft. The TPC is 19, GML 120 m, and LCF 3 m forward of midships. It is required to bring the vessel to an even keel draught of 8.5 m. Calculate the mass which should be added and the distance of the centre of the mass from midships. (10)

(a) Explain how an increase of draught and of displacement influence rolling. (6)

(b) A pontoon has a constant cross-section as shown in Fig. Given below. The metacentric height is 2.5 m. Find the height of the centre of gravity above the keel. (10)

(a) Describe the fundamental principle of a propeller. (6)

(b) A propeller 6m in diameter has a pitch ratio of 0.9, BAR 0.48, and, when turning at 110 rev/min, has a real slip of 25% and wake fraction 0.30. If the propeller delivers a thrust of 300 kN and the propeller efficiency is 0.65, calculate: (10)

(a) Blade area

(b) Ship speed

(c) Thrust power

(d) Shaft power

(e) Torque

(a) Explain what is meant by: (6)

(i) Wave-making resistance

(ii) Frictional resistance

(iii) Eddy-making resistance

(b) When a ship is 800 nautical miles from port its speed is reduced by 20%, thereby reducing the daily fuel consumption by 42 tonnes and arriving in port with 50 tonnes on board. If the fuel consumption in t/h is given by the expression (0.136+0.001V^3) where V is the speed in knots, estimate: (10)

(i) The reduced consumption per day

(ii) The amount of fuel on board when the speed was reduced

(iii) The percentage decrease in consumption for the latter part of the voyage

(iv) The percentage increase in time for this latter period

(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 of 5000 tonnes displacement has a double bottom tank 12 m long. The 1/2 breadths of the top of the tank are 5, 4 m and 2 m respectively. The tank has a watertight centreline division. Calculate the free surface effect if the tank is partially full of freshwater on one side only. (10)

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

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

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

With reference to dry docking, define the responsibilities of the Second Engineer and instructions to Junior Engineers:

(a) Prior to docking.

(b) Whilst the vessel is in dry dock.

(c) Prior to flooding and leaving the dock.

With reference to Statutory Certification:

(a) State the reason for the freeboard requirements.

(b) (i) Explain the term conditions of assignments.

(ii) List the items that may be examined during a related survey.

State how and why the following machinery items are affected 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.

(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 to each type.

(a) Describe how the distribution of mass within the ship affects the rolling period. (6)

(b) The righting moments of a ship at angles of heel of 0, 15°, 30°, 45° and 60° are 0, 1690, 5430, 9360 and 9140 kNm respectively. Calculate the dynamical stability at 60°. (10)

(a) Describe briefly the significance of the factor of subdivision. (6)

(b) A ship 120m long has a light displacement of 4000 tonne and LCG in this condition 2.5m aft of midships. The following items are then added: (10)

Cargo 10000 tonne LCG 3.0m forward of midships

Fuel 1500 tonne LCG 2.0 m aft of midships

Water 400 tonne LCG 8.0m aft of midships

Stores 100 tonnes LCG 10.0m forward of midships

Using the following hydrostatic data, calculate the final draughts:

(a) Explain how the distribution of masses affects rolling and pitching. (6)

(b) A ship turns in 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. (10)

(a) Describe the effect of cavitations on the propeller blades. (6)

(b) A propeller 4.6m diameter has a pitch of 4.3m and boss diameter of 0.75m. The real slip is 28% at 95 rev/min. Calculate the speed of advance, thrust and thrust power. (10)

(a) Describe the stability requirements of a ship for dry-docking. (6)

(b) A ship 130m long displaces 14000 tonnes when floating at draughts of 7.5m forward and 8.10 m 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. (10)

(a) Describe a method for the attachment of bilge keels. (5)

(b) State THREE reasons for not extending bilge keels to the entire length of the vessel. (6)

(c) Explain TWO principles of roll damping that bilge keels exploit. (5)

Vessel has gone through very heavy weather. On arrival at safe anchorage, you are conducting your inspection to determine damages to hull.

(a) List the areas you will inspect. (3)

(b) List your findings of any significance. (6)

(c) Write a report to company suggesting repairs if any (7)

With reference to ship's rudder state:

(a) Why a breached hollow rudder can add to fuel costs? (6)

(b) Why excessive pintle clearance should not be tolerated? (5)

(c) Why fitted bolts are used in connecting upper and lower stocks? (5)

With reference to International Load Line Statutory Certification,

(a) State the reasons for the freeboard requirements (6)

(b) (i) Explain the term "conditions of assignments" (5)

(ii) List the items that may be examined during a Load line survey after a vessel's major repairs in the dry dock. (5)

(a) Sketch a transverse section through the hold space of a Bulk Carrier hull (8)

(b) Referring to the sketch in (a) describe how adequate structural strength is built into the hull. (8)

(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 the mean TPC is 15 tonne (10)

(a) Describe stability requirement for dry-docking. (6)

(b) A box shaped vessel, 50 metres long x 10 metres wide, floats in salt water on an even keel at a draft of 4 metres. A center 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)

(a) Define longitudinal center of gravity (LCG) and longitudinal center of buoyancy(LCB). (6)

(b) A ship 120m long floats at 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)

(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, 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)

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 5.5m and the speed of advance is 11 Knots. Find: (10)

(i) Real Slip

(ii) Wake fraction

(iii) Propeller thrust, when its efficiency, η = 70%

(a) Describe a method for the attachment of bilge keels. (5)

(b) State THREE reasons for not extending bilge keels the entire length of the vessel. (6)

(c) Explain TWO principles of roll damping that bilge keels exploit. (5)

(a) Describe a method for the attachment of bilge keels. (5)

(b) State THREE reasons for not extending bilge keels the entire length of the vessel. (6)

(c) Explain TWO principles of roll damping that bilge keels exploit. (5)

With reference to ship's rudder state:

(a) Why a breached hollow rudder can add to fuel costs? (6)

(b) Why excessive pintle clearance should not be tolerated? (5)

(c) Why fitted bolts are used in connecting upper and lower stocks? (5)

With reference to International Load Line Statutory Certification,

(a) State the reasons for the freeboard requirements. (6)

(b) (i) Explain the term "conditions of assignment". (5)

(ii) List the items that may be examined during a Load line survey after a vessel's major repairs in the dry dock. (5)

(a) Sketch a transverse section through the hold space of a container ship hull (8)

(b) Referring to the sketch in (a) describe how adequate structural strength is built into the hull. (8)

(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 sandbank at the following low water is 3.2 metres. Calculate the GM at that time, assuming that the KM will then be 5.0 metres and that the mean TPC is 15 tonne. (10)

(a) Describe stability requirement for dry-docking. (6)

(b) A box shaped vessel, 50 metres long x 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 15 metres long and contains cargo with permeability 30%. Calculate the list if this compartment is bilged. KG = 3 metres. (10)

(a) Define longitudinal center of gravity (LCG) and longitudinal center of buoyancy (LCB). (6)

(b) A ship 120m long floats at draughts of 5.50m forward and 5.80m aft. MCT Icm 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)

(a) List the precautions necessary before an inclining experiment is carried out. (6)

(b) The speed of a ship is increased to 18% above normal for 7.5 hours, 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)

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 5.5m and the speed of advance is 11 knots. Find: (10)

(i) Real slip

(ii) Wake fraction

(iii) Propeller thrust, when its efficiency, η = 70%

Vessel has gone through very heavy weather. On arrival at safe anchorage, you are conducting your inspections to determine damages to hull.

(a) List the areas you will inspect.

(b) List your findings of any significance.

(c) Write a report to company suggesting repairs if any

Explain how the period of roll varies with:

(a) The amplitude of roll.

(b) The radius of gyration.

(c) The initial metacentric height.

(d) The location of masses in the ship

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 surveying authority.

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

Describe a method for the attachment of bilge keels. State THREE reasons for not extending bilge keels for the entire length of the vessel. Explain TWO principles of roll damping that bilge keels exploit.

List SIX hazards that arise with the carriage of liquefied gas in bulk. Describe, with the aid of a sketch, the details of construction of a prismatic cargo tank within a gas carrier designed to carry liquefied gas (LPG)

A ship of 15000 tonne displacement has an Admiralty Coefficient, based on shaft power, of 420. The mechanical efficiency of the machinery is 83%, shaft losses 6%, propeller efficiency 65% and QPC 0.71. At a particular speed the thrust power is 2550kW. Calculate: (16)

(i) indicated power,

(ii) effective power,

(iii) ship speed.

(a) Describe stability requirements for dry-docking. (6)

(b) A ship of 8000t displacement floats upright in sea water, with KG= 7.6m, GM= 0.5m. A tank, whose kg is 0.6m above the keel and 3.5m from the center line, contains 100 t of water ballast. Neglecting the free surface effect, calculate the angle which the ship will heel, when the ballast water is pumped out. (10)

(a) Define longitudinal center of gravity (LCG) and longitudinal centre of buoyancy (LCB). (6)

(b) The immersed cross-sectional areas of a ship 120 m long, commencing from aft are 2, 40, 79, 100, 103, 104, 104, 103, 97, 58 and 0 m2. Calculate: (10)

(i) displacement

(ii) longitudinal position of the centre of buoyancy.

With respect to Buoyancy of a vessel:

(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)

A ship of length 140m, Breadth of 18.5m, draught of 8.1 m and a displacement of 17,025 tonnes in sea water, has a face pitch ratio of 0.673. The diameter of the propeller is 4.8m. The results of the speed trial show that true slip may be regarded as constant over a range of 9 to 13 knots and is 30%, w = 0.5Cb-0.05. If fuel used is 20t/day at 13 knots and fuel consumption/day varies as cube of speed of ship, determine the fuel consumption, when propeller runs at 110 pm. (16)

(a) Explain the six types of ship motions along different axes. Discuss the causes of these motions and their impact on the vessel’s stability and performance. (8)

(b) Discuss the methods employed to reduce these motions and enhance the vessel’s stability and comfort. (8)

Describe the relationship between frictional resistance and

(a) Ship speed. (4)

(b) The wetted surface area. (4)

(c) The surface roughness. (4)

(d) The length of the vessel. (4)

During a voyage, sea water is found leaking into the engine room through a small hole in the ship side plating. What type of repairs will you carry out as an immediate action as a second engineer? What are the other actions and reporting procedures undertaken by the vessel to comply with class and flag requirements and procedures? How will you ensure that prompt and thorough repairs are undertaken as a permanent measure? (16)

(a) List SIX hazards associated with the carriage of liquefied gas in bulk. (8)

(b) Sketch and describe the details of construction of a free-standing prismatic tank within a gas carrier designed to carry liquefied gas (LPG). (8)

(a) With reference to fatigue of hull structures explain the influence of stress level and cyclical frequency on expected operating life. (6)

(b) Explain the influence of material defects on the safe operating life of forged components of stern fittings. (5)

(c) 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. (5)

(a) List the variables which affect the force on a rudder. (6)

(b) A triangular bulkhead is 7 m wide at the top and has a vertical depth of 8 m. Calculate the load on the bulkhead and the position of centre of pressure if the bulkhead is flooded with sea water on only side.

(i) to the top edge

(ii) with 4 m head to the top edge. (10)

(a) Explain the effect on GM during the filing of a double – bottom tank. (6)

(b) The length of a ship is 18 times the draught. while the breadth is 2.1 times the draft. At the load water plane, the water plane area co-efficient is 0.83 and the difference between the TPC in sea water and the TPC in fresh water is 0.7. Determine the length of the ship and TPC in fresh water.

(a) What is meant by the Admiralty Coefficient and the Fuel Coefficient? (6)

(b) A ship of 14900 tonne displacement has a shaft power of 4460 kW at 14.55 knots. The shaft power is reduced to 4120 kW and the fuel consumption at the same displacement is 541 kg/h. Calculate the fuel coefficient for the ship. (10)

(a) Describe the stability requirements of a ship for dry-docking. (6)

(b) The ½ ordinates of a waterplane at 15m intervals, commencing from aft, are 1, 7, 10.5, 11, 11, 10.5, 8, 4 and 0m. Calculate: (10)

(i) TPC.

(ii) Distance of the centre of flotation from midships.

(iii) Second moment of area of the waterplane about a transverse axis through the centre of flotation.

(a) Describe the effect of cavitations on the propeller blades (6)

(b) The following data are available from the hydrostatic curves of a vessel.

Calculate the TPC at a draught of 5.05m. (10)

State how and why the following machinery items are affected 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.

(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 category of watertight door and state the regulation pertaining to each type.

(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 coating which are available.

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 surveying authority.

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

With regard to 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 tank.

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

(a) Explain why the bilging of empty double-bottom or deep tanks below the waterline leads to an increase in GM. (6)

(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 center of gravity. (10)

(a) Describe the ways in which an unstable ship can be made stable. (6)

(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 = 7.5m, calculate the KG. (10)

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

(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.

f = 0.42 and n = 1.825. (10)

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

(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 is perpendicular to the plane of the rudder is given by: F = 577 Av² sin α.

Allow 20% for the race effect. (10)

(a) List the components of residual resistance.

(b) The following data are available for a twin-screw vessel:

Calculate the service speed if the brake power for engine is 3500kW. The transmission efficiency loss is 3% and the allowances for weather and appendages 30%. (10)

(a) Describe a method for the attachment of bilge keels. (5)

(b) State THREE reasons for not extending bilge keels the entire length of the vessel. (6)

(c) Explain TWO principles of roll damping that bilge keels exploit. (5)

Vessel has gone through very heavy weather. On arrival at safe anchorage, you are conducting your inspection to determine damages to hull.

(a) List the areas you will inspect. (3)

(b) List your findings of any significance. (6)

(c) Write a report to company suggesting repairs if any (7)

With reference to ships rudder plate:

(a) Why a breached hollow rudder can add to fuel costs? (6)

(b) Why excessive pintle clearance should not be tolerated? (5)

(c) Why fitted bolts are used in connecting upper and lower stocks? (5)

With reference to International Load Line Statutory Certification,

(a) State the reasons for the freeboard requirements. (6)

(b) (i) Explain the term "conditions of assignment". (5)

(ii) List the items that may be examined during a Load line survey after a vessel's major repairs in the dry dock. (5)

(a) Sketch a transverse section through the hold space of a container ship hull. (8)

(b) Referring to the sketch in (a) describe how adequate structural strength is built into the hull. (8)

(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 the mean TPC is 15 tonne. (10)

(a) Describe stability requirement for dry-docking. (6)

(b) A box shaped vessel, 50 metres long x 10 metres wide, floats in salt water on an even keel at a draft of 4 metres. A center 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)

(a) Define longitudinal center of gravity (LCG) and longitudinal center of buoyancy(LCB). (6)

(b) A ship 120m long floats at 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)

(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, 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)

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 5.5m and the speed of advance is 11 Knots. Find: (10)

(i) Real Slip

(ii) Wake fraction

(iii) Propeller thrust, when its efficiency, n = 70%

(a) Define hogging and sagging with the help of neat sketches. Explain the causes of these structural conditions and when they are most likely to occur during a voyage. (8)

(b) Discuss the effects of hogging and sagging on a ship’s structural integrity. What measures are taken in design, loading, and operation to minimize their impact? (8)

(a) Define the term angle of loll. Explain the conditions under which it occurs and support your answer with a diagram showing the stability curve and ship’s position at the angle of loll. (8)

(b) Describe the actions to be taken to correct the angle of loll and restore positive stability. What precautions must be taken during the corrective process to avoid worsening the situation? (8)

Discuss the need for adequate support of engine room gantry cranes, detailing the following

(a) Sketch section through the engine room casing showing how the crane is supported by the ship structure. (6)

(b) State what restricts the forward and aft limits of the crane and what is fitted to prevent the crane damaging the forward and aft bulkheads or casing. (5)

(c) State the Second Engineer’s responsibilities for the engine room gantry crane. (5)

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

(a) Explain in detail, how an underwater survey is carried out. (6)

(b) State the requirements to be fulfilled before an underwater survey is acceptable to the survey authority. (5)

(c) Construct a list of the items in order of importance that the underwater survey authority should include. (5)

Describe the effect of the following on the ship’s stability. (16)

(a) Ice formation on superstructures

(b) Effects of wind and waves

(c) Changes that takes place during the ships voyage

(d) Bilging of a compartment

(e) While water is being pumped out from the dry dock.

(a) Describe the stability requirements of a ship for dry-docking. (6)

(b) A ship of 8000 tonne displacement, 110m long, floats in sea water of 1.024 t/m3 at draughts of 6m forward and 6.3 m aft. The TPC is 16, LCB 0.6 m aft of midships, LCF 3m aft of midships and MCT1cm 65 tonne m, the vessel now moves into fresh water of 1.000 t/m3. Calculate the distance a mass of 50 tonne must be moved to bring the vessel to an even keel and determine the final draught. (10)

(a) Describe the effect of cavitations on the propeller blades. (6)

(b) A ship of 15000 tonne displacement has an Admiralty Coefficient, based on shaft power, of 420. The mechanical efficiency of the machinery is 83%, shaft losses 6%, propeller efficiency 65% and QPC 0.71. At a particular speed the thrust power is 2550 Kw. Calculate: (10)

(i) Indicated power

(ii) Effective power

(iii) Ship speed.

(a) With respect to Buoyancy of a vessel:

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)

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

(b) The immersed cross-sectional areas of a ship 120m long, commencing from aft are 2, 40, 79, 100, 103, 104, 104, 103, 97, 58 and 0 m2. Calculate:

(i) Displacement

(ii) Longitudinal position of the centre of buoyancy. (10)

(a) What is the effect on fuel consumption per unit time, if the ship’s speed is outside its operation range? (6)

(b) An oil tanker 160m long and 22m beam floats at a draught of 9m in seawater. Cw is 0.865. The midships section is in the form of a rectangle with 1.2m radius at the bilges. A midships tank 10.5m long has twin longitudinal bulkheads and contains oil of 1.4 m3/t to a depth of 11.5m. The tank is holed to the sea for the whole of its transverse section. Find the new draught. (10)

(a) Explain the six types of ship motions along different axes. Discuss the causes of these motions and their impact on the vessel's stability and performance. (8)

(b) Discuss the methods employed to reduce these motions and enhance the vessel's stability and comfort. (8)

Explain the GZ (Righting Arm) curve used in ship stability. Discuss its significance, the information that can be obtained from the curve, and its role in assessing a ship's stability under various conditions.

Explain the different types of framing systems used in ship construction. Discuss their design, structural arrangement, and advantages in ensuring the vessel's strength and stability. (16)

(a) List SIX hazards associated with the carriage of liquefied gas in bulk. (8)

(b) Sketch and describe the details of construction of a free-standing prismatic tank within a gas carrier designed to carry liquefied gas (LPG). (8)

(a) With reference to fatigue of hull structures explain the influence of stress level and cyclical frequency on expected operating life. (6)

(b) Explain the influence of material defects on the safe operating life of forged components of stern fittings. (5)

(c) 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. (5)

(a) List the variables which affect the force on a rudder. (6)

(b) A triangular bulkhead is 7 m wide at the top and has a vertical depth of 8 m. Calculate the load on the bulkhead and the position of centre of pressure if the bulkhead is flooded with sea water on only side: (10)

(i) To the top edge

(ii) With 4 m head to the top edge.

(a) Explain the effect on GM during the filing of a double - bottom tank (6)

(b) An oil tanker 160m long and 22m beam floats at a draught of 9m in seawater. Cw is 0.865. The midship section is in the form of a rectangle with 1.2m radius at the bilges. A midship tank 10.5m long has twin longitudinal bulkheads and contains oil of 1.4m3/t to a depth of 11.5m. The tank is holed to the sea for the whole of its transverse section. Find the new draught. (10)

(a) What is meant by the Admiralty Coefficient and the Fuel Coefficient? (6)

(b) A ship of 14900 tonnes displacement has a shaft power of 4460 kW at 14.55 knots. The shaft power is reduced to 4120 kW and the fuel consumption at the same displacement is 541 kg/h. Calculate the fuel coefficient for the ship. (10)

(a) Describe the stability requirements of a ship for dry-docking. (6)

(b) The ½ ordinates of a waterplane at 15m intervals, commencing from aft, are 1, 7, 10.5, 11, 11, 10.5, 8, 4 and 0m. Calculate: (10)

(a) TPC

(b) Distance of the centre of flotation from midships

(c) Second moment of area of the waterplane about a transverse axis through the centre of flotation.

(a) Describe the effect of cavitations on the propeller blades (6)

(b) The following data are available from the hydrostatic curves of a vessel.

Calculate the TPC at a draught of 5.05m. (10)

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

(a) Describe with the aid of a sketch, ONE method of building up the insulation: (5)

(b) State with reasons the alloy, which is used for the membrane. (5)

(c) Describe with the aid of a sketch, how the tanks are located and supported. (6)

(i) Longitudinally

(ii) Transversely

With reference to dry docking, define the responsibilities of the Second Engineer and instructions to Junior Engineers: (16)

(a) Prior to docking.

(b) Whilst the vessel is in dry dock.

(c) Prior to flooding and leaving the dock.

(a) Explain what is meant by “permissible length” of compartments in passenger ships. (6)

(b) Describe how the position of bulkheads is determined. (6)

(c) Briefly describe the significance of the factor of subdivision. (4)

Explain how the period of roll varies with

(a) The amplitude of roll. (4)

(b) The radius of gyration. (4)

(c) The initial metacentric height. (4)

(d) The location of masses in the ship. (4)