NAVAL MEO Class 2 Written Question (APR 2023)

EXAMINATION OF MARINE ENGINEER OFFICER

NAVAL ARCHITECTURE

M.E.O. CLASS II

TIME - 3 HOURS Total Marks - 100

Q1: With reference to dry docking, define the responsibility of the second engineer;

A. Prior to docking;

B. Whilst the vessel is in dry dock;

C. Prior to flooding and leaving the dock.

Q2. With reference to rudder carrier beings fitted to Merchant Ships:

A. Sketch a bearing designed to transfer the full weight of the rudder to ships structure.

B. Describe the consequence If the rudder carrier bearing surfaces become heavily scored.

C. Describe the consequence of and the action to be taken, if the carrier shatters.

Q3. 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.

Q4. 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; B. State which alloy is used for the membrane and the reason; C. Explain why a secondary barrier is installed. i) Longitudinally; ii) Transversely

Q5. A. Describe a method of the attachment of bilge keels;

B. State THREE reasons for not extending bilge keels the entire length of the vessel;

C. Evaluate the effectiveness of bilge keels for large wall sided vessels;

D. Explain TWO principles of roll damping those bilge keels exploit.

Q6. A. Describe the stability requirements of a ship for dry-docking.

B. A ship of 8000 tonne displacement, 110m long, floats in sea water of 1.024t/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 1.000t/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.

Q7. 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:

(i) Indicated power, (ii) Effective power, (iii) Ship speed.

Q8. 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?

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 1m. Calculate the second moment of area of the tank surface about a longitudinal axis passing through its centroid.

Q9. A. Define longitudinal centre of gravity (LCG) and longitudinal centre of buoyancy (LCB).

B. The immersed cross-sectional area 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.

Q10. A. What is the effect on fuel consumption per unit time, if the ship’s speed is outside its operation range?

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.