3.6 Stability booklet
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Statutory Documents - IMO Publications and Documents - International Codes - 2008 IS Code – International Code on Intact Stability, 2008 - Part B – Recommendations for ships engaged in certain types of operations, certain types of ships and additional guidelines - Chapter 3 – Guidance in preparing stability information - 3.6 Stability booklet

3.6 Stability booklet

  3.6.1 Stability data and associated plans should be drawn up in the working language of the ship and any other language the Administration may require. Reference is also made to the International Safety Management (ISM) Code, adopted by the Organization by resolution A.741(18). All translations of the stability booklet should be approved.

  3.6.2 Each ship should be provided with a stability booklet, approved by the Administration, which contains sufficient information to enable the master to operate the ship in compliance with the applicable requirements contained in the Code. The Administration may have additional requirements. On a mobile offshore drilling unit, the stability booklet may be referred to as an operating manual. The stability booklet may include information on longitudinal strength. This Code addresses only the stability-related contents of the booklet.footnote

 3.6.3 The stability manual for ships engaged in anchor handling operations should contain additional information on:

  • .1 maximum bollard pull, winch pull capacity and brake holding force;

  • .2 details on the anchor handling arrangement such as location of the fastening point of the wire, type and arrangement of towing pins, stern roller, all points or elements where the tension is applied to the ship;

  • .3 identification of critical downflooding openings;

  • .4 guidance on the permissible tensions for each mode of operation and for each set of towing pins, including any physical element or arrangement that can restrict the wire movement, as function of all relevant stability criteria; and

  • .5 recommendations on the use of roll reduction systems.

 3.6.4 The stability booklet for ships engaged in harbour, coastal or ocean going towing operations and/or escort operations should contain additional information on:

  • .1 maximum bollard pull;

  • .2 details on the towing arrangement, including location and type of the towing point(s), such as towing hook, staple, fairlead or any other point serving that purpose;

  • .3 identification of critical down-flooding openings;

  • .4 recommendations on the use of roll reduction systems;

  • .5 if any wire, etc. is included as part of the lightship weight, clear guidance on the quantity and size should be given;

  • .6 maximum and minimum draught for towing and escort operations;

  • .7 instructions on the use of the quick-release device; and

  • .8 for ships engaged in escort operations, the following additional operating information should be included:

    • .1 a table with permissible limits of the heel angle in accordance with the criteria included in paragraph 2.7.3.4 as function of loading condition and escort speed; and

    • .2 instructions on the available means to limit the heel angle within the permissible limits.

 3.6.5 For ships engaged in lifting operations, for which section 2.9 applies, additional documentation should be included in the stability booklet:

  • .1 maximum heeling moment for each direction of lift/inclination as a function of the counter-ballast heeling moment, if used, the draught, and vertical centre of gravity;

  • .2 where fixed counter ballast is used, the following information should be included:

    • .1 weight of the fixed counter ballast; and

    • .2 centre of gravity (LCG, TCG, VCG) of the fixed counter ballast;

  • .3 loading conditions over the range of draughts for which lifting operations may be conducted with the maximum vertical load of the lift. Where applicable, righting lever curves for both before and after load drop should be presented for each loading condition;

  • .4 limitations on crane operation, including permissible heeling angles, if provided;

  • .5 operational limitations, such as:

    • .1 Maximum Safe Working Load (SWL);

    • .2 maximum radius of operation of all derricks and lifting appliances;

    • .3 maximum load moment; and

    • .4 environmental condition affecting the stability of the ship;

    • .6 instructions related to normal crane operation, including those for use of counter ballast;

    • .7 instructions such as ballasting/de-ballasting procedures to righting the ship following an accidental load drop;

    • .8 identification of critical down-flooding openings;

    • .9 recommendations on the use of roll reduction systems;

    • .10 drawing of the crane showing the weight and centre of gravity, including heel/trim limitations established by the crane manufacturer;

    • .11 a crane load chart, with appropriate de-ratings for wave height;

    • .12 load chart for lifting operations covering the range of operational draughts related to lifting and including a summary of the stability results;

    • .13 a crane specification manual provided by the manufacturer shall be submitted separately for information;

    • .14 the lifting appliance load, radius, boom angle limit table, including identification of offlead and sidelead angle limits and slewing angle range limits and reference to the ship's centreline;

    • .15 a table that relates the ship trim and heel to the load, radius, slewing angle and limits, and the offlead and sidelead limits;

    • .16 procedures for calculating the offlead and sidelead angles and the ship VCG with the load applied;

    • .17 if installed, data associated with a Load Moment Indicator system and metrics included in the system;

    • .18 if lifting appliance (crane) offlead and sidelead determine the maximum ship equilibrium angle, the stability booklet should include a note identifying the lifting appliance as the stability limiting factor during lifting operations; and

    • .19 information regarding the deployment of (stability) pontoons to assist a lifting operation, if fitted.

    • The information in subparagraphs .2 to .19 above may be included in other ship specific documentation on board the ship. In that case, a reference to these documents shall be included in the stability booklet.

  3.6.6 For ships carrying timber deck cargoes:

  • .1 comprehensive stability information should be supplied which takes into account timber deck cargo. Such information should enable the master, rapidly and simply, to obtain accurate guidance as to the stability of the ship under varying conditions of service. Comprehensive rolling period tables or diagrams have proved to be very useful aids in verifying the actual stability conditions;footnote

  • .2 the Administration may deem it necessary that the master be given information setting out the changes in deck cargo from that shown in the loading conditions, when the permeability of the deck cargo is significantly different from 25% (refer to 3.5.3); and

  • .3 conditions should be shown indicating the maximum permissible amount of deck cargo having regard to the lightest stowage rate likely to be met in service.

  3.6.7 The format of the stability booklet and the information included will vary dependent on the ship type and operation. In developing the stability booklet, consideration should be given to including the following informationfootnote:

  • .1 a general description of the ship;

  • .2 instructions on the use of the booklet;

  • .3 general arrangement plans showing watertight compartments, closures, vents, downflooding angles, permanent ballast, allowable deck loadings and freeboard diagrams;

  • .4 hydrostatic curves or tables and cross curves of stability calculated on a free-trimming basis, for the ranges of displacement and trim anticipated in normal operating conditions;

  • .5 capacity plan or tables showing capacities and centres of gravity for each cargo stowage space;

  • .6 tank sounding tables showing capacities, centres of gravity, and free surface data for each tank;

  • .7 information on loading restrictions, such as maximum KG or minimum GM curve or table that can be used to determine compliance with the applicable stability criteria;

  • .8 standard operating conditions and examples for developing other acceptable loading conditions using the information contained in the stability booklet;

  • .9 a brief description of the stability calculations done including assumptions;

  • .10 general precautions for preventing unintentional flooding;

  • .11 information concerning the use of any special cross-flooding fittings with descriptions of damage conditions which may require cross-flooding;

  • .12 any other necessary guidance for the safe operation of the ship under normal and emergency conditions;

  • .13 a table of contents and index for each booklet;

  • .14 inclining test report for the ship, or:

    • .14.1 where the stability data is based on a sister ship, the inclining test report of that sister ship along with the lightship measurement report for the ship in question; or

    • .14.2 where lightship particulars are determined by other methods than from inclining of the ship or its sister, a summary of the method used to determine those particulars;

  • .15 recommendation for determination of ship's stability by means of an in-service inclining test.

  3.6.8 As an alternative to the stability booklet mentioned in 3.6.1, a simplified booklet in an approved form containing sufficient information to enable the master to operate the ship in compliance with the applicable provisions of the Code as may be provided at the discretion of the Administration concerned.

Parent topic: Chapter 3 – Guidance in preparing stability information
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