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 Based on ISO power yacht stability standards. Design category A assumed. ````Based on ISO power yacht stability standards `Design category "A" assumed MACRO ISOY-FLD PAGE \\----\ \ISO POWER YACHT - DOWNFLOODING (6.1)\ \Downflood Height (6.1.2)\ \Downflooding Angle (6.1.3)\ \----\ \\\\>>>> Heel induced by passenger crowding <<<<\ \\ CRTPT OFF CRTPT (1) "%1" %2 %3 %4 HEEL = 0 SOLVE STATUS WEIGHT, CRTPT /NOREF Part = hull Refpt = %2, %3, %4 `<--- Downflooding point VARIABLE h SET h = {Lh} DIV 17 \ \(6.1.2) Downflood height above waterplane = {height}\ \This height must be > {h:2} (hull length/17.0)\ mac pass \PASSES\ // mac fail \FAILS!\ // IF {height}>{h} THEN .pass ELSE .fail LIM OFF LIM TITLE DOWNFLOODING ANGLE (6.1.3) LIM ANGLE FROM EQU TO FLD > 25 LIM ABS ANGLE AT FLD > 30 VARIABLE t SET t = 24 MINUS {Lh} SET t = {t} TIMES {t} TIMES {t} SET t = {t} DIV 600 SET t = {t} PLUS 10 LIM ANGLE AT EQU < {t} \\\Max heel angle at equilibrium = 10 + (24 - {Lh})^3 / 600 = {t:2}\ PAGE RA 0 5 /LIM:ATT /GRAPH:NONE / MACRO ISOY-WW PAGE \\----\ \ISO POWER YACHT RESISTANCE TO WAVES & WIND (6.3)\ \Rolling in Beam Waves & Wind (6.3.1)\ \----\ \\\\>>>> Heel induced by wind <<<<\ \Heeling moment = {HMMT}\ \\ HEEL = 0 SOLVE HMMT REPORT \ STATUS WEIGHT /NOREF VARIABLE x SET x = 10 DIV {DISPL} PLUS 24 \\\\\Roll angle = 24 + 10 / {DISPL} = {x:2}\ ROLL = {x} HEEL = *-ROLL LIM OFF LIM TITLE ROLLING IN WAVES & WIND (6.3.1) LIM RATIO FROM ROLL TO ABS 50 OR FLD > 1 PAGE RA 0 5 /LIM:ATT / MACRO ISOY-W PAGE \\----\ \ISO POWER YACHT RESISTANCE TO WAVES & WIND (6.3)\ \Resistance to Waves (6.3.2)\ \----\ \\\\ HEEL = 0 SOLVE STATUS WEIGHT /NOREF MACRO B LIM RA AT MAX TO ABS 30 > 0.2 \\Area requirement is 0.2 m-rad.\ // MACRO C VARIABLE x SET x = 30 MINUS {HEEL} TIMES 0.057 PLUS 3.15 LIM AREA: DEGREES LIM AREA FROM ABS 0 TO MAX > {x} \\Area requirement = 3.15 + ( 30 - {HEEL} ) x 0.057 = {x} m-rad.\ // LIM OFF LIM TITLE RESISTANCE TO WAVES (6.3.2) LIM ABS ANGLE AT MAX > 15 RA 0 5 ... 120 /STOP:MAX /HOLD /NOPRINT \\\\Angle of maximum righting arm = {HEEL:2} degrees.\ IF {HEEL} < 30 THEN .C ELSE .B HEEL = 0 SOLVE PAGE RA 0 5 /LIM:ATT / macro sample read my.gf units mt `<--- Metric units required variable Lh set Lh = 29.6 `<---- Put length of hull here weight = 145.0 `<------ full load weight w/o passengers lcg = 14.339 `<------ full load lcg w/o passengers vcg = 1.804 `<------ full load vcg w/o passengers ADD "28 People up dk" 2.100, 10.67, 2.92, 5.953 `<--- Offset loading ADD "57 People mn dk" 4.275, 15.13, 2.74, 3.591 `<--- Offset loading .ISOY-FLD "Engine vent" 17.09, 1.52, 3.75 `<--- Downflooding point ADD "28 People up dk" *, *, 0.0, * /nowarn `<--- Normal loading ADD "57 People mn dk" *, *, 0.0, * /nowarn `<--- Normal loading HMMT = 17.017 `<--- Wind heeling moment .ISOY-WW HMMT OFF .ISOY-W / `.sample ``` Add a free link to your site