APPENDIX 11 - STABILTIY INFORMATION BOOKLET CONTENTS
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Statutory Documents - MCA Publications - The Workboat Code Edition 2 - APPENDIX 11 - STABILTIY INFORMATION BOOKLET CONTENTS

APPENDIX 11 - STABILTIY INFORMATION BOOKLET CONTENTS

 The outlines of the required stability information are set out in MSN 1752, schedule 6.

A Model Stability Information Booklet specifically for workboats is not available but sufficient information exists to enable the creation of one, using the guidance below.

It should be remembered that the primary purpose of the Stability Information Booklet is to assist the vessel’s master and operator to use the vessel safely. Its secondary function is to enable a Naval Architect / consultant to confidently assess the stability characteristics of the vessel based on easily obtainable draft and loading data. It should not be used as a repository for superfluous data (as is often the case with automatically generated reports: Naval Architects should select the automated populating criteria appropriately). A competent Naval Architect should be able to compile a full stability book for most vessels which is less than 60 pages – including damaged survivability and crane operating conditions.

Where limiting KG curves / data is included including instructions on their use, and the vessel is of certain types (for example pontoon barges with no below deck tankage or loadable spaces, or propelled vessels with very limited possibilities of loading, or a dedicated pilot boat), it may be acceptable, at the discretion of the Certifying Authority, not to include a GZ curve and GZ based stability analysis for each example loading condition. In this case it would be sufficient to indicate the deadweight items, locations, and free surface moments etc., used in the loading condition; to calculate the final draught trim and heel; to demonstrate that the condition is compliant with the limiting KG requirements; and demonstrate the size of margin available. Crane conditions would need to show compliance with KG requirements (upright) and the resulting heel angle / minimum freeboard.

The Booklet should include the items below where applicable:

SCHEDULE of CONTENTS Notes
Front Cover   Name of vessel It should cover all essential items to assess the provenance and applicability of the SIB
    Intact stability information booklet (or Intact and damaged if applicable)
    Date of issue
    Version number
    Name and address of Naval Architect
       
Contents   Contents with page numbers Reports without page numbers should not be accepted
       
General Particulars   Ships name General particulars to confirm applicability of the book to the vessel, assess the operational envelope and identify responsible persons in the build and operation
    Official number
    Port of registry
    Certifying Authority
    Number of persons carried
    Maximum weight of cargo
    Area of operation
    Name and address of owners
    Class
    Material of construction
    Yard number
    Builder's name and address
    Fitted out by (if different)
    Date of build
    Date of commissioning
    Dimensions
    Length overall
    Length BP
    Moulded beam
    Depth
    Rake of keel
    Displacements: fully laden, Lightship
    Draughts: fully laden, Lightship
    Minimum freeboard: Lightship Freeboard
    Gross and Net tonnage
    Nomenclature/Abbreviations/ Glossary Desirable but not essential if definitions are included
       
General Arrangement   Profile drawing - Including definition of FP, AP, midships, base line (when not included above) Protocol for trims +/-ve Datums used throughout should be clearly indicated
    Plan drawing. Downflooding openings can be included in this or succeeding section  
       
Arrangement of Tanks and Ballast   Plan and profile views showing tank positions and position of any permanent ballast. Can be included in GA above or tank usage below in operating conditions  
       
Arrangement of Sections   An explanation of how the booklet is arranged. Booklet arranged in sections so that the most essential matters are brought to the user's attention first. The criteria against which stability is assessed should be referenced (e.g. MGN 280 section 11; MGN 437; this document (The Safety of Small Workboats and Pilot Boats – a Code of Practice))
    Section 1 – Operational / stability information
    Section 2 - Technical data and loading conditions
    Section 3 - Reference information including Lightship and VCG derivation
    Basis information:

Name and version number of stability software used; responsible agent/cy for carrying out the inclining experiment (or VCG weight estimate in the case of some multihulls) and supplying the dimensions/drawings for modelling.

       
Section 1   Stability information  
  1.1 Special notes regarding the stability of the ship, including the Intact (and damaged if applicable) standard code reference criteria, ie section 11.3.8 or 11.3.9 herein:  
    Example of static stability curve with details of Area A, Area B, Area C, Point X, Maximum GZ and Initial GM  
    Pass or fail status of the vessel and where 11.3.9 is used as alternative criteria  
  1.2 General instructions for the Master: Keeping copy of SIB on board and in date; loading conditions not to be exceeded, Freeboard marks not to be immersed, record of minor modifications Any modifications, minor or otherwise, should be advised to the CA. If necessary a SIB addendum to the approved SIB can be issued.
  1.3 Tank usage and free surface moments and effect on stability (where not already included above)  
  1.4 General precautions against capsizing and downflooding: Area of Operation, Stability Criteria, Weather, Reference to location of downflooding openings  
  1.5 Cargo condition summary, maximum load, height and position. Reference to Limiting KG data for non-standard conditions.  
  1.6 Sample load condition table and instructions for use.  
  1.7 Maximum VCG (KG) Curve / table with appropriate range of displacement and trim and instructions for use. Example showing the use of the maximum KG curve and trim calculation. Blank calculation page/s also recommended. Others copies can be made.
  1.8 Statement ref. maximum crane load (kg) and maximum outreach (m) (if applicable) and any other relevant advice ref. crane operation, such as the provision and use of an inclinometer  
       
    Stability data  
  1.9 GZ Curve - condition 1 - Fully Laden Departure including critical downflooding angle. Data including DISP, Draft FP, Draft AP GZ curve may be omitted from load the condition where KG curves / data and instructions for their use is included.

It is desirable but not essential to include WSA, WPA, LCB, VCB, GZ, LCF, TCF, TCF against heel angle 0 to 90 degrees
    GZ data and assessment against criteria - Condition 1  
    Stability summary, detailing required criteria, achieved criteria, margin and pass/fail for following; Or as modified by the alternative criteria followed (e.g. 11.6.7 of MGN 280; Brown code)
    Area 0 deg. to 30 deg.  
    Area 0 deg. to 40 deg. or Downflooding Angle  
    Area 30 deg. to 40 deg. or Downflooding Angle  
    GZ at 30 deg. or greater  
    Angle at GZ max  
    GM  
    Downflooding angle  
       
  1.10 GZ Curve - condition 2 - Arrival 10% Consumables including critical downflooding angle. Data including DISP, Draft FP, Draft AP GZ curve may be omitted from load the condition where KG curves / data and instructions for their use is included.

It is desirable but not essential to include WSA, WPA, LCB, VCB, GZ, LCF, TCF, TCF against heel angle 0 to 90 degrees
    Stability summary, detailing required criteria, achieved criteria, margin and pass/fail for following; Or as modified by the alternative criteria followed (eg 11.6.7 of MGN 280; Brown code)
    Area 0 deg. to 30 deg.  
    Area 0 deg. to 40 deg. or Downflooding Angle  
    Area 30 deg. to 40 deg. or Downflooding Angle  
    GZ at 30 deg. or greater  
    Angle at GZ max  
    GM  
    Downflooding angle  
       
  1.11 GZ Curve, GZ data and assessment against criteria for any other relevant load condition, for instance different load/passenger combinations. Limiting conditions which define the operational envelope should be included.

Operational conditions including any crane usage and a condition showing the maximum deck cargo.

 
    Summary of pass/fail margins and stability category for each load condition  
       
  1.12 Freeboard and draught marks  
    Depth from baseline to top of deck at midships (m)  
    Maximum fully laden draught at midships (m)  
    Minimum freeboard at midships (m)  
    Position of midships (metres aft of foreside of stem at deck level)  
    Diagram showing location and dimensions of freeboard mark  
    Where freeboard must be calculated by reference to Load Line Regulations 1998 (SI 1998 No. 2241), as amended (lifting device fitted; cargo over 1000kg) the calculation summary should be included either here or in an appendix (and referenced here)  
       
Section 2   Technical Data and Loading Conditions  
  2.1 Draught marks and hydrostatic datum  
    Drawing identifying draught marks and datum  
    Determination of draughts at AP and FP relative to Baseline from draughts read at marks  
  2.2 Angles of deck edge immersion and downflooding  
    Drawing identifying downflooding openings  
    Table listing each downflooding point, the area of each opening, the angle of immersion in each loadcase  
  2.3 Arrangement of tanks and ballast  
    Drawing showing tanks and ballast fitted  
    Table listing tank capacities, soundings, fluid, location, weight, LCG, VCG, TCG and maximum FSM  
    Notes on the use of Free Surface Moments  
    Include calculation of maximum free surface moment  
    Details of ballast weight and location  
    Reference to baseline, forward perpendicular, transverse origins and +ve -ve trim  
       
  2.4 Loading condition - Departure 100% consumables  
    Weights and centres table of lightship and deadweight items, referenced to LCG, VCG, TCG and Free Surface  
    Include Draught @ AP, Draught @ FP, Mean Draught, Trim, GM solid, Free Surface Correction GM fluid  
       
  2.5 Loading condition - Arrival 10% consumables  
    Weights and centres table of lightship and deadweight items, referenced to LCG, VCG, TCG and Free Surface  
    Include Draught @ AP, Draught @ FP, Mean Draught, Trim, GM solid, Free Surface Correction GM fluid  
       
    Make-up of all other load conditions which are presented in section 2 with weights and centres table of lightship and deadweight items, referenced to LCG, VCG, TCG and Free Surface  
       
Section 3   Reference information including Lightship and VCG Derivation  
  3.1 Hydrostatic data - Trim Forward (maximum envisaged in the operational envelope)  
    For an appropriate range of draughts: displacement, LCB, LCF, KB, KMT, KML, TPC, MTC. (WPA, WSA, dimensionless coefficients as desired may be included though are not necessary)  
  3.2 Hydrostatic data - Level Trim  
    For an appropriate range of draughts: displacement, LCB, LCF, KB, KMT, KML, TPC, MTC. (WPA, WSA, dimensionless coefficients as desired may be included though are not necessary)  
  3.3 Hydrostatic data - Trim Aft (maximum envisaged in the operational envelope)  
    For an appropriate range of draughts: displacement, LCB, LCF, KB, KMT, KML, TPC, MTC. (WPA, WSA, dimensionless coefficients as desired may be included though are not necessary)  
       
  3.4 Intermediate trims should be included where maximum trim is over 0.3m, to enable reasonably accurate interpolations  
       
  3.5 KN Data - Trim forward (maximum envisaged in the operational envelope)  
    For an appropriate range of displacement vs. appropriate range of heel angle  
       
  3.6 KN Data - Level Trim  
    For an appropriate range displacement vs. appropriate range of heel angle  
       
  3.7 KN Data - Trim aft (maximum envisaged in the operational envelope)  
    For an appropriate range displacement vs. appropriate range of heel angle  
       
    Intermediate KN data should be included where maximum trim is over 0.3m, to enable reasonably accurate interpolations  
       
  3.8 Notes on the use of KN Data  
    Insert hull section drawing illustrating the relative positions of K, M, G, GZ and B  
       
  3.9 Inclining Experiment Report  
    List Vessel, Type, Location, Date and Time, Weather, Sea state, SG of water, Condition of vessel,  
    Tank ullages, Persons present, Inclining weights, Pendulum length(s)  
    Forward and aft draughts, mean draught, trim  
    Lists of weights and centres (VCG,LCG) to come off and to go on  
    Inclined displacement derived from draughts and trims Where lightship particulars of a sister vessel are based on a lightship check the inclining report for the ‘lead’ sister vessel should be included in the stability information of the subsequent sister/s.
    List of pendulum readings  
    GM calculation (averaged)  
    Displacement, LCG, KMT, GMT, Free Surface Correction, VCG (KG) in inclined condition  
       
  3.10 Lightship derivation  
    Weights and centres table of items to be removed  
    Weights and centres table of items to be added  
    Weights and centres summary  
       
  3.11 Record of modifications to lightship  
       
  3.12 Crane  
    Crane Model  
    Crane Position  
    Load radius diagram  
    Including freeboard and angle of heel at maximum heeling moment, compliance with KG requirement  
    All personnel to be on deck when lifting  
    All principal openings to remain closed when lifting.  
    Restriction on lifting over “crane” side.  
    Vessel to have no residual heel prior to lift.  
    Variation from standard load-radius diagram for crane.  
    Any additional load and outreach data that may be relevant particularly if crane off centreline  
       
  3.13 Damaged stability condition.  
    Summary of worst damaged compartment condition and criteria assessed against, together with pass (or fail) margins and a sketch showing the equilibrium waterline  
    Equilibrium conditions of other damaged compartment conditions may also be included if relevant or pass fail margins are similar to the worst condition.  
       
  3.14 Beaufort scale of Wind Speeds and Corresponding Pressures  
  3.15 Metric/Imperial conversion  
       
    Appendix for Freeboard calculation to Load Line Regulations where required by Load Line Regulations 1998 (SI 1998 No. 2241), as Amended, under code section 12.2.4  
Parent topic: The Workboat Code Edition 2
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