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A trend in recent years in the education of professional
seafarers has been to reduce the time that the student actually
spends in college and for the introduction of a more structured
learning experience whilst the student is actually at sea. With
most educational establishments there is an urgency to
develop 'distance learning' based courses. This trend is likely
to become more popular with students undertaking academic
training courses, but one that is also setting a real challenge to
lecturers, like myself.
Traditional classroom teaching techniques will always have a
place in the education of seafarers. However, with the
growing availability of PC access on board modem ships it is
envisaged that, with the aid of appropriate software, students
will be more able to prepare themselves for the short periods
of very intense study required of them during their college
phases. This software is specifically designed for this purpose.
It is my experience that many students, resulting from their
lack of mathematical ability, often meet the subject of ship
stability with apprehension. This is the main reason for the
downfall of many students studying this topic. This program is
designed to address this problem by covering the subject
content in the simplest way possible and at an assumed
mathematical level that is appropriate for a learner studying
independently. Worked examples and self-assessment
questions (SAQ's) are provided throughout for the learner to
assess his her progress. At the end of each section tutorial
questions are provided with solutions fully worked out. All
such questions are designed to be of a type and standard that
are likely to be encountered in real examinations at OOW
level.
It is this approach which gives this work an added advantage
over most modem text books on the subject of ship stability,
were a high level of mathematical ability is often assumed. It
has often been the experience of many students to encounter
worked examples in text books that are not sufficiently broken
down to enforce proper understanding. Formulae are derived
where appropriate to enhance understanding.
Look through the contents of the program that follows.
Those highlighted in blue must be studied for the OOW level
examinations.

Contents

SECTION 1 - INTRODUCTION
SECTION 2 - BASIC PRINCIPLES
Introduction
2.1 Density, Mass and Volume
2.2 The Laws of Flotation
2.3 Simple box-shaped vessel calculations.
Tutorial questions
SECTION 3 - FORM COEFFICIENTS
Introduction
3.1 Coefficient of fineness of the water-plane area (Cw)
3.2 Block Coefficient (Cb)
3.3 Midships Coefficient (Cm)
3.4 Longitudinal Prismatic Coefficient (Cp).
Tutorial questions
SECTION 4 - TONNES PER CENTIMETRE IMMERSION
Introduction
4.1 Tonnes per centimetre immersion (TPC)
4.2 TPC formula.
4.3 Factors affecting TPC
4.4 Interpolation of hydrostatic data
4.5 Load/discharge problems
Tutorial questions
SECTION 5 - LOAD LINES
Introduction
5.1 Factors for consideration in assigning a freeboard
5.2 Type 'A' and Type ’B’ ships
5.3 Load line dimensions
5.4 Fresh Water Allowance (FWA)
5.5 Dock Water Allowance (DWA)
5.6 Load Line calculations
Tutorial questions
SECTION 6 CENTRE OF GRAVITY (G) AND
CENTRE OF BUOYANCY CB)
Introduction
6.1 Centre of gravity
6.2 Effect of shifting a weight already on board
6.3 Effect of loading a weight
6.4 Effect of discharging a weight
6.5 Multiple weight problems
6.6 Centre of buoyancy (B)
Tutorial questions
SECTION 7 - TRANSVERSE STATICAL STABILITY
Introduction
7.1 Transverse Statical Stability
7.2 Righting lever (GZ)
7.3 Moment of statical stability (Righting moment)
7.4 Initial Transverse Metacentre (M)
7.5 Metacentric Height (GM)
7.6 Calculating Righting Moments at small angles of heel
Tutorial questions
SECTION 8 - CONDITIONS OF STABILITY
Introduction.
8.1 Stable condition
8.2 Neutral condition
8.3 Unstable condition and angle of loll
Tutorial questions
SECTION 9 - INITIAL TRANSVERSE METACENTRE
Introduction
9.1 Initial Transverse Metacentre explained
9.2 Calculating KM for box-shaped vessels
9.3 Use of the metacentric diagram
9.4 To determine the final KG required to complete loading
with a required GM
9.5 Factors affecting KM
Tutorial questions
SECTION 10 - FREE SURFACE EFFECT
Introduction
10.1 Free surface effect and transverse statical stability
10.2 To calculate the effect of free surface in a rectangular
shaped tank
10.3 Free surface moments
10.4 Representation of free surface data in ship's tank
sounding/ullage tables
10.5 Factors influencing free surface effect
Tutorial questions
SECTION 11 - CURVES OF STATICAL STABILITY
(GZ CURVES’)
Introduction
11.1 Calculating GZ values
11.2 Procedure for constructing a curve of statical stability
11.3 Information available from a curve of statical stability
11.4 Curves of statical stability for stiff and tender ships
Tutorial questions
SECTION 12 LIST
Introduction
12.1 Calculating list caused by a transverse shift of weight -
the basic list triangle
12.2 Calculating list caused by a transverse and vertical shift of
weight - ship initially upright
12.3 Calculating the list due to a single weight being loaded or
discharged
12.4 Shifting a weight already on board to bring a listed ship
upright
12.5 Multiple weight problems - ship initially upright
12.6 Multiple weight problems - ship initially listed
12.7 Loading weights about the centre-line to complete upright
12.8 List and free surface effect
Tutorial questions
SECTION 13 - CURVES OF STATICAL STABILITY
FOR VARYING CONDITIONS STABILITY
Introduction
13.1 Curve of statical stability for a ship in a stable condition
13.2 Curve of statical stability for a ship in a neutral condition
of stability
13.3 Curve of statical stability for a ship in an unstable condition
13.4 Curve of statical stability for a ship that is listed
13.5 Correcting an angle of loll
Tutorial questions
SECTION 14 - SUSPENDED WEIGHTS
Introduction
14.1 Effect on KG of lifting a weight using ship’s gear
14.2 Loading a weight using ship’s lifting gear
14.3 To calculate the maximum permissible KG required prior
to loading or discharging a weight to ensure that a certain
list limit is not exceeded
Tutorial questions
SECTION 15 - INTRODUCTION TO TRIM
Introduction
15.1 Terms relating to ship length
15.2 Draught marks and reading the draught
15.3 Trim
15.4 Change of trim
15.5 Moment to change trim by one centimetre (MCTC)
15.6 Formula for calculating MCTC
15.7 Longitudinal centre of flotation (LCF or F)
15.8 Calculating the final draughts when a weight is shifted
15.9 The effect of loading and discharging weights
15.10 Multiple weight problems
15.11 Weight to shift to reduce the trim by a specified amount
15.12 Weight to load to bring a ship to an even keel
15.13 Weight to transfer to reduce the deepest draught by
specified amount
Tutorial questions
SECTION 16 - TRIM USING HYDROSTATIC DATA
Introduction
16.1 True mean draught - displacement when out of trim
16.2 Calculating the true mean draught
16.3 Trim calculations using hydrostatic data
16.4 Trim by consideration of the relative positions of the LCB and
LCG
Tutorial questions
SECTION 17 INCLINING EXPERIMENT
Introduction
17.1 Calculating the KG as inclined
17.2 Calculating the light ship KG and displacement
17.3 Precautions prior to conducting the experiment
17.4 Precautions to ensure accuracy of the calculation
Tutorial questions
SECTION 18 - ASSESSING COMPLIANCE OF A SHIP'S
LOADED CONDITION WITH IMP CRITERIA
Introduction
18.1 Simpson's First Rule
18.2 Simpson's Second Rule
18.3 Intact stability criteria for all ships (IMO)
18.4 Dynamical stability - the relevance of area under the curve
of statitcal stability
18.5 Unreliability in practice of statical stability data
Tutorial questions
SECTION 19 - PRACTICAL SHIP LOADING PROBLEMS
Introduction
19.1 Introduction to loading sheet data
19.2 Practical ship load problem
Tutorial questions