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Q1. With respect to the sacrificial anodes fitted to a ship’s hull.

A. State the purpose of fitting anodes to a hull structure.

B. Describe with the aid of sketch, how anodes may be attached to the hull.

C. Upon inspection in dry- dock it is found that the anodes have not wasted and areas of hull structure have experienced severe corrosion. Explain possible reasons for this situation.

Q3. Give a reasoned opinion as to the validity of the following assertions concerning ship structure:

A. Crack propagation in propeller shaft ‘A’ brackets or spectacles frames is indicative of inadequate scantlings and strength;

B. The adequate provision of freeing ports is as critical to seaworthiness as watertight integrity.

Q1. (a) What is free surface effect? How can be avoided or reduced.
(b) Give the components of ships resistance while vessel is ‘enroute’.

Q1. (a) Draw the mid ship section of a double hull oil tanker & name each part.

(b) What is Bow Flare? Why is it so important in Bulk Carriers?

Q3. (a) Considering the vessel as a compound beam define Bending moment shearing force. Which is the point of Maximum Bending Moment?

(b) Sketch and Describe Hatch coaming of a large bulk carrier.

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

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.

Q10. A. List the precautions necessary before an inclining experiment is carried out.

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.

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

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.

Q1. With reference to International Load Line Statutory Certification,

A. State the reasons for the freeboard requirements;

B. (i) Explain the term “conditions of assignments”;

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

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 5.5m and the speed of advance is 11 Knots. Find:
i. Real Slip
ii. Wake fraction
iii. Propeller thrust, when its efficiency, η = 70% (10)