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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 / write 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 = ABS {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 view report off |

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