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46 CFR 171.080 (f) (6) (iii)
    `46 CFR 171.080 (f) (6) (iii) requires the area between equilibrium and
    `downflooding or the second intercept to be > 0.0025 (equ - 1) m-rad.
    `This variable area requirement can be calculated and used in the limit
    `definition.  Since the limit is static after the limit command has been
    `issued, it will not serve for maximum VCG calculations.  But it can be
    `applied to individual cases where the heel angle at equilibrium is known.
    `The following run demonstrates how this can be done.
    proj 171080f6
    `Create a simple hull with compartments sufficient for this example:
    enter pm
    units mt
    create hull
    ends 0 100
    top 14
    bot 0
    out 15
    margin 0.5
    create cmpt1.s
    ends 40 50
    inb 10
    fit hull
    create cmpt2.s
    ends 50 60
    inb 10
    fit hull
    quit pm
    report /nograph
    `Derive a weight and CG:
    draft 8
    vcg 8
    solve weight, lcg
    `Define a point of downflooding:
    crtpt = "Downflooding point" 70, 15, 15
    `Define a heeling moment (wind and/or passengers):
    hmmt 20000
    `Flood two compartments:
    type (cmpt1.s,cmpt2.s) = flood
    `Issue the limits:
    limit (1) angle at EQU < 15
    limit (2) angle from EQU to RA0 > 20
    variable A,H
    solve `(finds the equilibrioum heel angle)
    set H = {HEEL} minus 1
    set A = {H} times 0.0025 `(this assumes metric units)
    limit (3) area from EQU to RA0 or FLD > {A}
    \Equilibrium heel angle = {HEEL:2} degrees\
    \Area required = 0.0025 * {H:2} = {A:4}\
    `Calculate and evaluate the righting arm curve:
    ra /lim
    report off

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