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Salvage example. Finds ground reactions as tide rises.
    `Salvage example.  Finds ground reactions as tide rises.
    proj salv
    read tanker.gf
    report /nofoot
    
    `Macro for reporting a condition:
    macro stat
    solve
    `Note - for more detail, remove the :total parameters.
    status weight:total, displ, wpl:total, crtpt
    /
    
    `Tank loads before grounding:
    load = (fodt*,do*,lo*,fw*) = 0.5
    load (cg*) = 0.95
    load (cgc2*) = 0.75
    load (cgc5*) = 0.75
    cont (cg*) = CHEMICALS, 0.8
    
    `Fixed weight before grounding:
    `(If the lightship & added weights & CGs are known they can be used in
    ` lieu of finding the total fixed weight & CG from the waterplane.)
    heel = 0
    trim = 2.5a        `<-- trim angle before grounding
    draft @ 0 = 7.75   `<-- draft at origin
    vcg = 6.5          `<-- known or assumed VCG
    solve weight, lcg  `<-- derives the fixed weight & CG from the waterplane
    
    \===== Free-floating condition before grounding =====\
    .stat
    
    `Tank changes since grounding:
    type (wbdb3.s,wbdb2.s,wbdb1.s,cgc3.c,cgc4.c,cgc2.s) = flooded
    
    `Waterplane as grounded:
    heel = 7.5
    trim = 5.8
    crtpt (4) "Survey point 1", 75.0f, 7.72s, 9.28
    height (4) = 7.0
    
    `Ground points in ship's coordinate system:
    `       label  est. reaction    location          -dist from hull
    ground = "A",       *         86f,   0,  0, /pen: -1.0
    ground = "B1",      *         78f,   0,  0, /pen: -0.5
    ground = "B2",      *         78f,   2,  0, /pen: -0.5
    ground = "C1",    500         70f,  2p,  0
    ground = "C2",    400         70f,   3,  0
    ground = "D1",    200         60f,  2p,  0
    ground = "D2",    100         60f,   3,  0
    ground = "E",       0         50f,  2p,  0
    ground = "F",       0         50f,   4,  0
    ground = "G",       0         45f,   0,  0, /pen: -2.5
    ground = "H",       0         40f,   0,  0, /pen: -5.0
    
    macro tide
    page
    \====== Tide level at %2 ======\
    depth = *%1
    .stat
    /
    
    page
    \==== As surveyed after grounding ====\
    .stat
    
    `Increase tide levels:
    `     increment   time
    .tide   "+.7"    "15:00"
    .tide   "+.7"    "16:00"
    .tide   "+.6"    "17:00"
    .tide   "+.5"    "18:00"
    .tide   "+.4"    "19:00"
    .tide   "+.1"    "19:30"
    
    report off
    
    macro view
    view salv.pf
    /
    
    .view
    
    

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