Elements and Performance Criteria

General context
Work must be carried out in compliance with mandatory rules and regulations and IMO Conventions and Codes including the relevant sections of the AMSA Marine Orders and ensuring that applicable codes, guidelines and standards recommended by IMO, the classification societies and maritime industry organisations are taken into account.

Work is performed independently under broad operational requirements, with accountability and responsibility for self and others in achieving the prescribed outcomes.

Work involves the application of fundamental principles of vessel construction and theories of trim and stability and stress in the development and implementation of measures to preserve the trim and stability of a vessel across a wide and often unpredictable range of normal and emergency operational contexts. The development of a broad strategy and techniques for controlling vessel trim, stability and stress is required. Accountability and responsibility for self and others in achieving the outcomes is involved.

Work requires significant judgement in technical, organisational and leadership functions related to controlling the trim and stability of vessels of 500 gross tonnage or more.

Worksite environment
Vessel may include any Australian or international commercial vessel of 500 gross tonnage or more (in the case of masters), or 3,000kW propulsion power (in the case of engineers).

Measures to control the trim and stability of the vessel may be carried out:
by day or night in both normal and emergency situations
under any possible conditions of weather and loading
while loading and unloading
while underway
during berthing and unberthing operations
while anchoring or mooring
when bunkering.

Measures to control the trim and stability of the vessel may include:
adjusting weight distribution of load
pumping ballast water to compensate for load distribution
pumping of flooded compartments
implementing damage control measures to maximise watertight integrity of hull where it has been damaged.

Sources of information/documents
Documentation/records may include:
ISM Code safety management system plans, procedures, checklists and instructions
operational orders
IMO Conventions and Codes
AMSA Marine Orders
IMO SOLAS Convention
vessel's log
'Trim and Stability Booklet'
company procedures
vessel manufacturer's instructions and recommended procedures
instructions of relevant Maritime Authorities
relevant Australian and international standards
Class Society Rules.

Applicable International, Australian and State/Territory regulations and legislation
Applicable procedures and codes may include:
IMO Codes and Conventions related to vessels of 500 gross tonnage or more
relevant sections of AMSA Marine Orders concerning vessel trim and stability
IMO SOLAS Convention
relevant international, Australian and State/Territory OH&S legislation.

Critical aspects of evidence to be considered
Assessment must confirm appropriate knowledge and skills to:
Monitor and control the trim and stability of the vessel:
safely in both normal and emergency situations
in normal and adverse weather conditions
when loading and unloading
when underway
in berthing and unberthing operations
when anchoring or mooring
when bunkering
Communicate effectively with others concerning operations to maintain the trim, stability and stresses of the vessel.

Interdependent assessment of units
This unit of competency must be assessed in conjunction with other mandatory units that form part of a job role of a master or chief mate on a ship of 500 gross tonnage or more, or a chief engineer officer or second engineer officer on a ship of 3,000kW propulsion power or more. The second engineer must also be able to take over the chief engineer's duties in an emergency situation.

Required knowledge and skills
Knowledge of relevant sections of the IMO Conventions and Codes and AMSA Marine Orders
Relevant OH&S legislation, codes of practice, policies and procedures
Theory and calculations of vessel stability and dynamics including:
computation of hydrostatic stability data of a ship
calculation of a ship's centre of gravity, centre of buoyancy and metacentre
calculation of the transverse and longitudinal stability using hydrostatic data
calculation of the moment of statical stability at small angles of heel
determination of the centre of gravity of a ship using an inclining experiment and effect of suspended weights
determining the required correction for the height of centre of gravity (kg) for the free surface effect
determination of the values of the righting lever and construction of righting lever curves
Calculations for change of draught, trim and heel when entering different water densities and due to bilging of compartments:
changes to draught, trim and heel due to adding or removing fuel, ballast or cargo
displacement, wetted surface, form coefficients, tonne per centimetre immersion, application of Simpson's rules to first and second moments of area, centroids and centres of pressure
Potential problems related to the control of trim and stability for vessels of 500 gross tonnage or more and appropriate action and solutions, including:
free surface of a liquid
shift of cargo
wind heel
handling of heavy weights
excessive trim
large swell conditions
dry docking
grounding
Principles of synchronous rolling and methods for its control, including an understanding of the effect on the rolling period of a vessel due to the radius of gyration
Causes and repercussions of a heeling vessel
Principle features of the structure of a vessel
Properties and application of materials used in vessel construction
Construction, layout and subdivision requirements of a typical vessel, including and understanding of freeboard and bulkhead deck, watertight compartments, weathertight compartments, the bulkhead of the vessel and collision bulkhead
Typical construction features, stress characteristics, forces on ships under various conditions or ships of 500 gross tonnage or more (in the case of masters), or 3,000kW propulsion power (in the case of engineers)
The principal stresses which act on the structure of a vessel, including panting and pounding
Steps involved interpreting and analysing a vessel's dynamic stability and comparing it against the IMO's minimum stability criteria
Basic procedures and precautions for the repair and maintenance of a vessel
Effects of density of sea water on the draught and freeboard of a vessel
Features of the load-line and draught marks of a vessel and procedures for carrying out related calculations
Procedures for calculating the required load distribution to achieve the desired trim
Typical problems related to the control of trim and stability for ships of 500 gross tonnage or more (in the case of masters), or 3,000kW propulsion power (in the case of engineers) and appropriate action and solutions, including:
problems concerning the strength of structural members to resist liquid pressure and loading due to a head of liquid.
problems involving shearing force and bending moments of a loaded ship in still water
Simple treatment of vibration
Bilge and ballast systems
Leveling arrangements for damaged side compartments.

Resource implications
Access is required to opportunities to either:
participate in a range of exercises, case studies and other simulated practical and knowledge assessments that demonstrate the skills and knowledge to maintain the trim and stability of a vessel in a range of operational situations, and/or
maintain the trim and stability of a vessel in a range of operational situations either:
using a simulator, meeting the requirements of Section A I/12 of the IMO STCW Code, over an appropriate range of simulated loading and operational situations
in appropriate practical situations on an operational commercial or training vessel.

Consistency in performance
Applies underpinning knowledge and skills when:
controlling the trim and stability and managing the stresses of a vessel
identifying and evaluating trim, stability and stress problems and determining an appropriate courses of action
identifying and implementing improvements to procedures for the control of trim and stability of a vessel
applying safety precautions relevant to manoeuvring operations
assessing trim and stability of vessel in both normal and emergency situations.

Shows evidence of application of relevant workplace procedures including:
relevant sections of IMO Conventions and Codes and AMSA Marine Orders
ISM Code and associated vessel's Safety Management System and procedures
OHS regulations and hazard prevention policies and procedures
job procedures and work instructions
relevant manufacturer's guidelines relating to the trim, stability and stress limits of the vessel
quality procedures (where existing)
procedures to protect the integrity and security of the vessel's hull
environmental protection procedures when pumping ballast water.

Action taken promptly to report and/or rectify out-of-limit trim, stability and stresses of the vessel in accordance with manufacturer's instructions, statutory requirements and company procedures.

Work is completed systematically with required attention to detail.

Context for assessment
Assessment of competence must comply with the assessment requirements of the relevant maritime regulations.

Assessment of this unit must be undertaken within relevant marine authority approved and audited arrangements by a registered training organisation:
As a minimum, assessment of knowledge must be conducted through appropriate written/oral examinations
Appropriate practical assessment must occur:
at the registered training organisation, and/or
on an appropriate working or training vessel.