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Demonstrates a method to find the Maximum Steady Heel Angle to Prevent Downflooding in Gusts. |

proj sailship `Demonstrates a method to find the ` "Maximum Steady Heel Angle to Prevent Downflooding in Gusts" MACRO MaxHeel VARIABLE T,TF0,TFL,TF,TMX,TSS,TSA VARIABLE GZF VARIABLE HA1,HA2 `Find downflooding angle: SET TFL=60.0 SET TMX=27.0 RA 0 10 ... 90 /STOP:FLD /HOLD /NOTAB SET TF0 = {HEEL} SET TF = {TF0} IF {TF} > {TFL} THEN SET TF = {TFL} `Find RA at max allowed DF angle: HEEL = {TF} SOLVE TRIM SET GZF = {RAH} `Calculate HA1, zero degree heeling arm to produce this heel: SET T = COS {TF} SET T = {T} POWER 1.3 SET HA1 = {GZF} DIV {T} `Calculate HA2, half of HA1: SET HA2 = {HA1} TIMES 0.5 `Set up heeling moment function using HA2: SET T = {HA2} TIMES {WEIGHT} HMMT = {T} /C:1.3 `Find heel under this HMMT: SOLVE SET TSS={HEEL} `Check whether exceeds allowed limit: SET TSA={TSS} IF {TSS}>{TMX} THEN SET TSA={TMX} HEEL 0 `Report: \ \Sailing Ship Maximum Allowed Steady Heel\ \ \Actual downdlooding angle: { TF0:2}\ \Maximum DF angle: { TFL:2}\ \Angle used for HA1: { TF:2}\ \GZ at this angle: { GZF:2}\ \ HA1: { HA1:2}\ \ HA2(0): { HA2:2}\ \Steady heel: { TSS:2}\ \Maximum steady heel: { TMX:2}\ \Allowed steady heel: { TSA:2}\ \\ / `Testing ... `Read a GF: read fv.gf `Define downflooding point: crtpt "Flood point" 0 10 13 `Set weight & CG: depth 5 vcg 5 solve weight lcg `Start report file: report `Execute the macro: .MaxHeel `Support with a righting arm curve: RA `View the result: report /preview report off |

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