1

Calculate stability

1.1

Vessel stability data book is accessed and checked for endorsement

1.2

Data is interpreted to determine vessel safety parameters

1.3

Stability is accurately calculated using data extracted from vessel stability data book

1.4

Stability calculations are checked to ensure they correlate with data set out in vessel stability book

1.5

Spurious or incorrect information is recognised and recalculated

1.6

Trim, draughts and list are adjusted as required

1.7

Stability calculations are conducted at a time, frequency and scope appropriate to voyage

2

Manage weight distribution

2.1

Stability calculations are used to plan weight distribution to ensure assigned load line conditions are not exceeded

2.2

Weight distribution is controlled to maintain vessel within acceptable stability and stress limits for loading operation and at all stages of voyage

2.3

Appropriate action is taken when weight distribution is compromising vessel safety

3

Maintain records of stability management

3.1

Data and information related to stability management is accurately recorded

3.2

Data and information related to stability management is filed and stored according to organisational procedures

Required Skills:

Apply knowledge of stability, trim and stress tables, diagrams and stress calculating equipment

Carry out calculations required when determining vessel stability and trim

Manage the loading and weight distribution of a vessel to ensure assigned load line conditions are not exceeded

Manage vessel stability in a range of conditions

Read and interpret vessel specifications and design drawings

Recognise problems affecting vessel stability and trim

Required Knowledge:

Calculation of vessels stability using the inclining experiment

Effects of angle of loll

Effects of beam and form coefficient on the stability of a vessel

Effects of density of sea water on the draught and freeboard of a vessel

Effects of free surface on the stability of a vessel

Features of the load-line and draught marks of a vessel and methods for performing related calculations

Fundamental actions to be taken in the event of partial loss of intact buoyancy

Fundamentals of watertight integrity

Principal stresses that act on the structure of a vessel

Principal structural members of a vessel and the proper names for various parts

Problems related to the control of trim, stability and stresses of vessels and appropriate action and solutions

Sections of the IMO, STCW and AMSA Marine Orders related to intact stability criteria

Stability, trim and stress tables, diagrams and stress calculating equipment

Theory and calculations of vessel stability and dynamics

Use of computer programs in calculating stability

Work health and safety (WHS)/occupational health and safety (OHS) requirements and work practices

The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, the required skills and knowledge, the range statement and the Assessment Guidelines for the Training Package.

Critical aspects for assessment and evidence required to demonstrate competency in this unit

The evidence required to demonstrate competence in this unit must be relevant to and satisfy all of the requirements of the Elements, Performance Criteria, Required Skills, Required Knowledge and include:

ensuring accuracy of calculations

attention to appropriate level of detail in recordkeeping.

Context of and specific resources for assessment

Performance is demonstrated consistently over time and in a suitable range of contexts.

Resources for assessment include access to:

industry-approved marine operations site or simulation where maintaining vessel stability can be demonstrated

tools, equipment and personal protective equipment currently used in industry

relevant regulatory and equipment documentation that impacts on work activities

range of relevant exercises, case studies and/or other simulated practical and knowledge assessments

appropriate range of relevant operational situations in the workplace.

In both real and simulated environments, access is required to:

relevant and appropriate materials and equipment

applicable documentation including workplace procedures, regulations, codes of practice and operation manuals.

Method of assessment

Practical assessment must occur in an:

appropriately simulated workplace environment and/or

appropriate range of situations in the workplace.

A range of assessment methods should be used to assess practical skills and knowledge. The following examples are appropriate to this unit:

direct observation of the candidate maintaining vessel stability

direct observation of the candidate applying relevant WHS/OHS requirements and work practices.

Guidance information for assessment

Holistic assessment with other units relevant to the industry sector, workplace and job role is recommended.

In all cases where practical assessment is used it should be combined with targeted questioning to assess Required Knowledge.

Assessment processes and techniques must be appropriate to the language and literacy requirements of the work being performed and the capacity of the candidate.

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below.

Stability calculations must include:

Calculation of areas under the curve

Changes in draft and trim due to differing water densities

Correction for free surface effect

Draft and trim

Metacentric height

Moment of statical stability at small angles of heel

Transverse and longitudinal stability

Values for righting levers and construction of the curve of stability

Appropriate action may include:

Amending the vessel loading plan

Ballast management

Reduction of free surface

Data and information related to stability management may include:

Cargo stowage and loading plan

Records of stability calculations

Safety management system

Stability and trim booklet