Calculating Cross Curves

The tables of drafts and heel angles are initially set-up by the system and you can both add to them and delete from them using the Add or Delete buttons respectively, or by using the simple right-hand button activated sub-menu approach as described above. Also you can select displacement to be the independent variable, instead of draft, by selecting the Appropriate Radio button. In this case the list box contains a list of displacements rather than drafts.

you can input any assumed initial trim and VCG condition and can define whether or not the vessel is allowed to freely trim or to maintain a Fixed Trim (by using the check box), regardless of the effects of different draft and heel conditions.

The Extreme drafts option, should be checked to indicate that the entered draft values are from the underside of keel (that means, include the keel thickness defined on the Ship Data dialog).

You are also able, by setting simple switches, to instruct Calc to create and show immersion curves for deck edge points, protected openings and unprotected openings, the relevant data for which will have been input on the Other Data node.

If the Heel to Port option is checked, then the ship will be inclined to port when calculating the cross curves; the default is to starboard.

Clicking the Axis Shift and Waves buttons within this dialog box results in you being presented with a dialog box for allowing these options to be used locally for the specific calculation.

If the Draw GZ curves for the following GM0's box is checked, then the program will produce a diagram with righting lever (GZ) curves for the given initial metacentric height (GM0) values.

If the Tabulate GM0 for following Tr's box is checked, then a table of initial metacentric heights (GM0) for the given rolling periods (Tr's) will be output.