Guidance

Naval Architecture Written Examination Syllabus

Published 6 May 2014

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The expected learning outcome is that the student.

1. Simpson’s Rule

1.1 Applies Simpson’s first rule (including subdivided intervals) to the determination of second moments of area.

  1. Derives the method of calculating the second moment of area of a plane about an end ordinate using Simpson’s Rule.
  2. Derives the method of calculating the second moment of area of a plane about its base using Simpson’s Rule.
  3. Calculates the second moment of area of a plane using 1.1.1 and 1.1.2.
  4. Uses the Theorem of parallel Axen in conjunction with 1.1.3 to determine the second moment of area of a plane about its neutral axis.
  5. Calculates the second moment of area of a waterplane about the centreline.
  6. Calculates the second moment of area of a waterplane about a transverse axis passing through its centroid.
  7. Calculates the second moment of area of an unsymmetrical tank top about a longitudinal axis passing through its centroid.

2. Free Surface Effect

2.1 Understands the effect of free surface liquids on transverse stability and solves problems involving free surface effect.

  1. Explains that the effect of a free surface is to cause a transverse shift of a ship’s centre of gravity when vessel heels.
  2. Explains that this transverse shift of centre of gravity has the same effect on the stability as a reduction in the transverse metacentric height.
  3. States an expression for the loss in metacentric height due to the free surface.
  4. Explains the meaning of “effective metacentric height”.
  5. Discusses the effect of tank divisions on free surface effect.
  6. Solves problems involving free surface effect.
  7. Discusses practical considerations of free surface of liquids, eg, the importance of restricting same and the methods of which it may be reduced.

3. Stability

3.1 Stability at Large Angle of Heel

3.1.1 Uses cross-curves of stability to produce curves of statical stability.

  1. Discusses the limitation of metacentric stability at large angles of heel.
  2. Explains how the cross-curves of stability can be obtained from ship sections for an assumed position of a ship’s centre of gravity.
  3. Uses the cross-curves of stability to predict the righting lever for any given displacement and for an assumed position of the centre of gravity.
  4. Calculates the necessary corrections to righting levers for the actual position of the ship’s centre of gravity.
  5. Sketches the final righting levers in the form of a statical stability curve.
  6. Shows that the initial slope of the stability curve may be obtained from the metacentric height.
  7. Defines range of stability.
  8. Solves problems on stability at large angles of heel.
  9. Defines dynamical stability.
  10. Calculates dynamical stability from statical stability curve or curve of righting moments.

3.2 Stability of Wall-Sided Vessels

3.2.1 Makes use of particular features of wall-sided vessels to obtain an approximation to the stability of a ship.

  1. States wall-sided formula for GZ values.
  2. Discusses the limitations of the wall-sided formula.
  3. Solves simple problems using the wall-sided formula.
  4. Applies the wall-sided formula to vessel with negative metacentric height to derive an expression for “Angle of Loll”.
  5. Solves problems using the Angle of Loll expression.
  6. Discusses procedures used to improve stability when at Angle of Loll.

3.3 Effect of Form on Stability

3.3.1 Understands the effects of form on stability.

  1. Discusses the effect of change of beam on the statical stability curve.
  2. Discusses the effect of freeboard on the statical stability curve.
  3. Discusses the effect of metacentric height on the statical stability curve.
  4. Sketches typical stability curves for different types of ship.

3.3.2 Stability information supplied to ships.

  1. Discusses the statutory requirements for the carriage of stability data on ships.
  2. Discusses the relevance of the area under the stability curve.

4.  Trim

4.1 Small Masses

4.1.1 Understands how to calculate the effects on the end draughts of addition, removal, or longitudinal movement of small masses.

  1. Defines Trim.
  2. Explains importance of the longitudinal centre of flotation (L.C.F.) in relation to trim problems.
  3. Explains that the mean draught of a ship is the draught at the L.C.F.
  4. Defines longitudinal metacentre.
  5. Defines longitudinal metacentric height.
  6. States an expression for the distance of the longitudinal metacentre above the centre of buoyancy.
  7. Derives an expression for the moment to change trim 1 cm.
  8. Determines change of trim due to longitudinal movement of small masses already on board.
  9. Determines the effect of small additions or removals mass on end draughts of a ship.
  10. Solves problems involving the end draughts after masses have been added, removed or moved longitudinally.

4.2 Large Masses

4.2.1 Understands how to use hydrostatic data to determine end draught of a ship.

  1. Demonstrates how geometrical properties are presented in the form of hydrostatic curves enumerating the curves concerned.
  2. Sketches a set of hydrostatic curves.
  3. Determines end draughts for loading conditions using hydrostatic curves or hydrostatic data.
  4. Determines the displacement of a ship, lying at a trimmed waterline.

4.3 Bilging

4.3.1 Solves problems on the change in end draughts of a box-shaped vessel due to bilging a compartment which is not at midships.

  1. Shows that when a compartment is bilged there can be changes in heel and or. in trim in addition to the change in mean draught.
  2. Calculates the displacement of B and G due to bilging.
  3. Calculates the second moment of area of the intact waterplane about its neutral axis.
  4. Calculates the effects of bilging on a non-midship compartment of a box-shaped vessel.

 4.3.2 Understands the elements in ship design which are included in order to reduce the effects of bilging.

  1. Discusses the effects of bilging.
  2. Discusses subdivision of vessels with transverse and longitudinal watertight bulkheads in cargo and passenger ships.
  3. Discusses the requirements indicated in 4.3.2.2.

5.  Rudders

5.1  Understands the principal forces acting on a ship and rudder, when helm is applied to a vessel.

  1. Explains that when the rudder is moved to an angle, from a moving ship’s centreline, a pressure build up on the forward side and a suction on the aft side of the rudder gives rise to a force (F) acting parallel to the ship’s centreline.
  2. States that the force acting on a rudder parallel to the ship’s centreline is given by F = kAV2.
  3. Expresses the force normal to the rudder as a component of the rudder force acting parallel to the ship’s centreline.
  4. Explains that the normal force acts at the centre of effort.
  5.  Calculates the torque applied by the rudder to the rudder stock.
  6. Applies the torsion equation in order to determine the minimum diameter of rudder stock given the maximum allowable shear stress in the stock material.
  7. Determines the work done in turning the rudder to a given angle from a graph of Torque against Rudder Angle.
  8. Derives an expression for the angle of heel produced due to the force on the rudder.
  9. Derives an expression for the angle of heel produced by a ship moving in a circular path.
  10. Solves problems involving heeling of a ship due to rudder being applied to the vessel.
  11. Describes types of rudder in use on merchant ships.
  12. Discusses the reasons for using balanced rudders.

6. Ship Resistance

6.1 Calculates the power required to drive a ship from the resistance to motion exerted by the water on a ship at any given speed.

  1. Applies the expression Rf = fsvn to determine frictional resistance to motion of a vessel given the empirical formulae for frictional coefficient ‘f’ of the form: F = A + B/(L +C).
  2. States Froudes Laws of Comparison.
  3. Explains the meaning of the term “corresponding speed”.
  4. Applies the law of comparison to determine the residuary resistance of a ship if the residuary resistance of a scale model of the vessel is known or can be determined.
  5. Explains the meaning of the terms:
    1. Effective Power (naked);
    2. Effective Power;
    3. Ship Correlation factor.
  6. Calculates the effective power requirements of a full sized ship given the total resistance to motion measured on a scale model of the vessel towed at the corresponding speed.

6.2 Propellers

6.2.1 Understands the relationships between powers measured at points between the ship’s engines and the propeller.

  1. Explains the meaning and use of:
    1. thrust deduction factor;
    2. hull efficiency;
    3. propeller efficiency;
    4. transmission efficiency;
    5. mechanical efficiency;
    6. propulsive coefficient;
    7. quasi propulsive coefficient.
  2. Develops the relationships between indicated power, shaft power, delivered power, thrust power and effective power.
  3. Solves numerical problems using the relation between powers.

6.2.2 Understands the phenomenon of propeller cavitation, its causes and its effects.

  1. Explains what is meant by cavitation.
  2. Explains that cavitation may cause erosion of the blade surface, vibration and reduction in efficiency.
  3. Explains that cavitation depends upon the net pressure of the blade surface and the vapour pressure of the water.
  4. Discusses the factors in propeller design which reduce cavitation.
  5. Discusses the practical reduction of cavitation by a ship’s staff.

6.3 Ships’ trials

6.3.1 Understands the reasons for carrying out ships’ trials, and the value of the data obtained from them.

  1. Explains that ship trials are carried out primarily to measure power and its related speed.
  2. Explains that there are progressive speed trials and full speed trials.
  3. Explains the value to ship staff and designers of the data measured during progressive trials.
  4. Explains that the opportunity is taken on ship trails to test all systems under working conditions.

6.4 Shear Force and Bending Moments in Still Water

6.4.1 Evaluates shear forces and bending moments on ships of simple geometric form.

  1. Identifies the purpose of a loading manual for a ship.
  2. Outlines the use of a stress indicator for a ship.
  3. Explains:
    1. weight curve of a ship;
    2. buoyancy curve of a ship.
  4. Shows that the load curve is the difference between the weight curve and the buoyancy curve.
  5. Illustrates that the shear force at any point in the length of a ship is represented by the area of the load curve on one side of the point.
  6. Uses 6.4.1.5 to produce a shear force diagram.
  7. Illustrates that the bending moment at any point in the length of a ship is represented by the area of the shear force on one side of the point.
  8. Uses 6.4.1.7 to produce a bending moment diagram.
  9. Solves problems on box shaped vessels floating in still water on level keel.

7. Ship Stresses

7.1 Recognises the causes and effects of stresses acting on ships.

  1. Explains the circumstances under which the following stresses may occur in a ships structure:
    1. torsional stresses;
    2. whipping stresses.
  2. Explains the steps taken to avoid or resist the stresses in 7.1.1.
  3. Explains the circumstances which may result in the following occurring in ships structures:
    1. brittle fracture;
    2. fatigue.
  4. Explains the steps taken to prevent the occurrence of brittle fracture and fatigue.
  5. Identifies the points of discontinuity in a ships structure and explains measures adopted to minimise their effects.

8. Ship Construction

8.1 Ship types

8.1.1 Recognises the problems associated with and the structural arrangements for the carriage of liquified gases.

  1. Explains the difference between LNG and LPG by describing their origins and quoting the following physical properties:
    1. boiling point;
    2. critical temperature.
  2. Describes the following cargo systems and identifies the gases for which they are suitable:
    1. fully pressurised;
    2. semi pressurised/semi refrigerated;
    3. semi pressurised/fully refrigerated;
    4. fully refrigerated at atmospheric pressure.
  3. Explains ‘secondary barrier’ and why it is required.
  4. Describes with the aid of sketches the following containment systems and how they are insulated:
    1. free standing-prismatic;
    2. free standing-spherical;
    3. membrane.
  5. Describes in broad outline how cargo boil-off is dealt with.
  6. Lists the safety devices fitted on board to ensure safe loading and unloading explaining their function.

8.1.2 Recognises the problems associated with and the structural arrangements for the carriage of chemical cargoes.

  1. Explains what is meant by compatibility and how it is catered for in chemical carriers with respect to:
    1. different cargoes;
    2. air;
    3. water;
    4. tank coatings;
    5. temperature;
    6. self reaction.
  2. Explains that chemical cargoes may be designated A, B or C according to the degree and nature of the hazard involved in their carriage.
  3. Explains that the cargo tank arrangements are governed by the cargo designation.
  4. Explains with the aid of sketches the tank arrangements for the cargoes designated in 8.1.2.2.
  5. Explains that protection of the structure in 8.1.2.4 can be achieved by suitable materials or coatings.
  6. Identifies the coatings and materials in 8.1.2.5 and cargoes for which they are suitable.
  7. Explains measures which should be taken by crew members to ensure personal safety.

8.1.3 Recognises the problems associated with the carriage of various cargoes.

  1. Summarises the conditions by arrangement of the loadline.
  2. Sketches the loadline naming the lines.
  3. Explains the problems involved in the carriage of the following cargoes:
    1. deck timber;
    2. grain;
    3. iron ore;
    4. concentrates.
  4. Explains the precautions which must be taken when carrying the cargoes in 8.1.3.3.

8.2 Tonnage and Freeboard

8.2.1 Analyses the Loadline Rules with particular reference to the “conditions of assignment”.

  1. Distinguishes terminology, “freeboard”, “freeboard deck”, “superstructure deck”, “Type A ship”, “Type B ship”, “superstructure”.
  2. Enumerates the criteria used as a basis for assigning freeboards:
    1. adequate ship strength;
    2. adequate reserve buoyancy;
    3. prevention of entry of water into hull;
    4. safe height of working platform and protection of crew;
    5. deck wetness in relation to bow height;
    6. stability and compartmentation.
  3. Explains various seasonal and fresh water loadline markings.
  4. Enumerate conditions for assigning basic minimum freeboard to tankers.
  5. Distinguishes main factors and describes maintenance required to maintain “conditions of assignment”:
    1. hatchways;
    2. machinery space openings;
    3. openings in freeboard and superstructure decks;
    4. vents, air pipes, cargo doors and other openings in hull below the freeboard deck;
    5. side scuttles, freeing ports;
    6. guard rails, gangways.
  6. Distinguishes between tabular freeboard, basic freeboard, assigned freeboard.
  7. Explains the conditions under which Type ‘B’ ship may be assigned a reduced freeboard.
  8. Distinguishes between gross and net tonnages.
  9. Determines the information required for tonnage measurement.
  10. Distinguishes between enclosed and excluded spaces.
  11. Analyses the function of the tonnage certificate and discusses the statement of information given.

8.3 Structural Materials

8.3.1 Integrates learning from different areas to explain the uses of materials other than mild steel for ships structures.

  1. Identifies the advantages and disadvantages of higher tensile and other special steels, aluminium alloys and glass reinforced plastics as constructional materials.
  2. Explains the uses of materials in 8.3.1.1 in ship construction.
  3. Identifies the problems encountered in the connection of aluminium to steel in ship construction.
  4. Illustrates a method used to overcome 8.3.1.3.

9. Classification, Structural Fire Protection, Life Saving Appliances and Pollution Control.

9.1 Analyses the function and influence of Classification Societies on the construction of ships.

  1. Determines the role of Classification Society in the design, building and operation of ships.
  2. Determines the nature of initial survey for award of class and intermediate/continuous surveys for retention of classification.
  3. Distinguishes between surveys for the various ship types i.e. oil tankers, dry cargo ships, refrigerated cargo ships, chemical tankers, gas carriers.
  4. Shows an understanding of classification notation.

9.2 Structural Fire Protection

9.2.1 Identifies in general terms the methods of structural fire protection for passenger ships and cargo ships.

  1. Explains that fire divisions are classified according to their degree of fire resistance.
  2. Describes, in broad outline only, the structural arrangements for fire protection of passenger ships.
  3. Outlines the requirements regarding:
    1. openings in A-class divisions;
    2. the protection of stairways, lift shafts and ventilation trunks.
  4. Describes the structural arrangements for fire protection of:
    1. dry cargo ships;
    2. oil tankers.

9.3 Life-Saving Appliances

9.3.1 Understands in broad outline the life-saving requirements  for merchant ships.

  1. Lists the following types of life-saving equipment:
    1. lifeboats;
    2. liferafts;
    3. lifebelts;
    4. life jackets;
    5. buoyancy equipment.
  2. Describes, with the aid of a sketch, a set of lifeboat gravity davits.
  3. Describes, with the aid of a sketch, the braking arrangements for the davits described in 9.3.1.2.
  4. Describes a launching procedure using the davits described in 9.3.1.2.

9.4 Pollution Control by Construction

9.4.1 Understands the facts and principles underlying the regulations for marine pollution control by construction.

  1. Explains the following:
    1. segregated ballast tanks;
    2. clean ballast tanks;
    3. protective locations;
    4. slop tanks.
  2. Explains the regulations relating to the items in 9.4.1.1.
  3. Explains the crude oil washing (COW) system for cargo tank cleaning.
  4. States the advantages and disadvantages of COW.

9.5 Vibration and Noise

9.5.1 Integrates learning from different areas to explain the causes and adverse effects of ship vibration and the methods used to prevent same.

  1. Defines the terms:
    1. frequency;
    2. amplitude;
    3. resonance;
    4. mode;
    5. node;
    6. anti-node.
  2. Explains that a ship will have natural frequencies of hull vibration.
  3. Points out that vibration may be caused by:
    1. the action of the sea;
    2. out-of-balance forces in main or auxiliary machinery;
    3. fluctuating forces on the propeller;
    4. propeller-hull interaction;
    5. operation of deck machinery.
  4. Points out that vibration may cause:
    1. structural failure;
    2. failure of equipment;
    3. discomfort to passengers and crew.
  5. Explains the effect of the following with regard to preventing or reducing vibration:
    1. stern design;
    2. propeller design;
    3. machinery seating arrangements;
    4. alteration of ships loading condition.

9.6 Noise

9.6.1 Recognises the problems of noise on ships and the methods used to reduce same.

  1. Discusses the sources of noise and how it is transmitted throughout a ship.
  2. Discusses how structural and machinery arrangement can reduce noise levels.
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