5.5 Master's instructions
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.456 – Guidelines for the Preparation of Intact Stability Information – (Adopted on 13 October 1986) - Annex - Guidelines for the Preparation of Intact Stability Information - 5 Category 2 - 5.5 Master's instructions

5.5 Master's instructions

 Instructions to the master in the use of the data provided under category 1 to obtain the draught, trim and stability characteristics appropriate to a loading condition meeting the requirements of 5.1 and the draught limitations in 5.2.

 These instructions should refer to numerical examples which may be drawn-up specifically for the purpose or to conditions of loading provided under 5.4.

 The instructions are to be precise and unambiguous. Sources of data within the document and other information should be clearly identified.

 Specific instructions should be given with regard to the following items:

  • .1 calculations of displacement and centres of gravity;

  • .2 calculation of draughts and trim;

  • .3 correct use of the data provided under 4.5 in obtaining free surface moment data for a given loading condition;

  • .4 lifting of form stability data from the information provided under 4.9 and correction to that data to account for the position of the ship's vertical centre of gravity (see.1) and for free surface effects (see.3);

  • .5 calculation of initial stability parameter (GM) corrected for the initial free surface effect (see 3);

  • .6 calculation of the ship's vertical centre of gravity corrected for the initial free surface effect (see.3);

  • .7 construction of righting lever (GZ) curves;

  • .8 construction of a heeling lever curve (as appropriate) relative to and on the same diagram as the righting lever (GZ) curve;

  • .9 evaluation of the GZ curve (also the heeling lever curve if appropriate) in relation to the specified stability criteria;

  • .10 evaluation of stability parameters, if appropriate, in relation to assumed wind and/or wave forces;

  • .11 where ballasting during a voyage is necessary, the master should be provided with guidance to ensure the stability of the ship;

  • .12 the correct operation of anti-rolling devices and/or heeling tanks and limitations on their use;

  • .13 use of the data provided under 5.3;

  • .14 use of any other data provided under category 1A which is required by the Administration to be included as necessary information in evaluating the stability of the ship;

  • .15 if information is provided under category 1B, instructions should be given as to its use if appropriate.

Parent topic: 5 Category 2
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