When the FSM command is not used when calculating righting arms, the CG shift
applies to the tanks and the righting arms are calculated using the fixed
weight and center. In the situation where a tank is frozen, how does the
software account for this weight when calculating righting arms? What effect
does this have on righting arms and area? I note that it is not indicated in
the fixed weight and center and the CG of the tank should not be able to
It is incorrect to think of the righting arms as being calculated using the
"fixed weight and center". The fixed weight and CG are shown in the RA table
header only to give some indication of the condition at hand (since the tank
CGs are possibly shifting and maybe there's spilling, nothing else applies at
all heel angles).
The righting arms are always calculated based on the total CG vs. the CB.
Therefore it doesn't matter whether or not some tanks are frozen: they are
always included in the total CG.
But you have a good point about the frozen tanks in that perhaps they should
be included in the fixed weight and CG in the RA table header since as long as
they are frozen they are certainly "fixed" as well. (Of course that wouldn't
change any of the righting arms but it might be helpful to someone trying to
understand how the frozen tanks are treated.)
Any time you have a question about how a righting arm is calculated, you can
see the details by means of the STATUS report. For example, suppose that you
wanted to know how the tanks are contributing to the righting arm at 45
degrees heel. You could do the following.
HEEL = 45
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