GHS
LIMIT commands based on Navy stability criteria 
Intact
severe wind and wave:
HMMT WIND /C2
ROLL = 25
LIM RISE > 0.667
LIM RESIDUAL RATIO FROM ROLL TO RA0 > 1.4
Lifting, Crowding & Turning:
HMMT = x /CS
LIM RISE > 0.667
LIM ABS ANGLE AT EQU < 15
LIM ABS RATIO FROM EQU TO RA0 > 1.667
Towline adds to Lifting:
LIM ANGLE FROM MAX TO ABS 40 OR FLD > 0
LIM ABS RATIO FROM EQU TO ABS 40 OR FLD > 1.667
Damage:
LIM ABS ANGLE AT EQU < 15
LIM RESIDUAL RATIO FROM ROLL TO ABS 45 OR FLD > 1.4
`roll angle depends on displacement
These interpretations of the Navy criteria are not necessarily appropriate
for every type of vessel in every loading condition and in all types
of service. Additional limit commands and/or changes to the parameters
as shown above may be needed in order to guarantee adequate stability.
A value attained for the RISE limit (A) can be converted to the value
of the ratio of righting arm at equilibrium to righting arm at max
(B) as follows:
B = 1 / (1 + A)
For example, A = 0.667 yields B = 0.6.
A value attained for the ABS RATIO limit (A) can be converted to the
value of the ratio of residual area to total area (B) as follows:
B = 1  1/A
For example, A = 1.667 yields B = 0.4.
To allow for offcenter weights, the transverse center of gravity
can be set to an appropriate value. If it is desired that the transverse
center of gravity of the total weight (including tanks) be 0.05, the
following command can be used:
WEIGHT (TOTAL) *, *, 0.05, *
This will set the transverse componenet of the light ship CG such
that the overall TCG comes out to be 0.05. Since the MAXVCG command
ignores the TCG (as well as tank loads), this will not affect MAXVCG
curves. 

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