{
  "title": "Harbor Draft Calculator Constants & Formula",
  "author": "Bryan Takahashi",
  "version": "2.0",
  "description": "Machine-readable specification for Raritan Bay clearance calculations. Grounded in NOAA Station 8518750 (Sandy Hook) tidal datum.",
  "datum": {
    "stationId": "8518750",
    "stationName": "Sandy Hook, NY",
    "chartDatum": "MLLW",
    "source": "https://tidesandcurrents.noaa.gov/stationPage.html?id=8518750",
    "coverageArea": "New York Harbor Approach, Raritan Bay Entrance"
  },
  "formula": {
    "effectiveWaterLevel": "tideHeight + channelDepth",
    "availableDepth": "effectiveWaterLevel - waveEffect",
    "waveEffect": "waveHeight * WAVE_COEFFICIENT",
    "minimumClearance": "availableDepth - keelDraft",
    "units": "feet (ft)"
  },
  "constants": {
    "WAVE_COEFFICIENT": {
      "value": 0.005,
      "unit": "dimensionless",
      "description": "Vertical excursion coefficient: ±0.5% LOA during wave passage (USCG coastal pilot conservative estimate)"
    },
    "MIN_SAFE_CLEARANCE_FOOT": {
      "value": 1.5,
      "unit": "ft",
      "description": "Recommended minimum clearance for safe passage"
    },
    "MIN_CRITICAL_CLEARANCE_FOOT": {
      "value": 0.5,
      "unit": "ft",
      "description": "Critical threshold requiring speed reduction"
    }
  },
  "boundaryConditions": {
    "validFor": [
      "Raritan Bay interior channels",
      "Arthur Kill approach",
      "Kill Van Kull entrance"
    ],
    "requiresAdjustmentFor": [
      "Open ocean swell (>3ft Hs)",
      "Hurricane-force winds",
      "Seismic event"
    ]
  },
  "validation": {
    "testCase": {
      "tideHeight": 4.2,
      "channelDepth": 45.0,
      "keelDraft": 12.0,
      "waveHeight": 2.5,
      "expectedClearance": 36.43
    },
    "methodology": "Subtract wave-induced vertical excursion from static water level, then compare against keel draft"
  },
  "crossLinks": {
    "homepage": "https://bryan-takahashi.4ort.net/harbor-draft-calculator.html",
    "documentation": "https://bryan-takahashi.4ort.net/harbor-draft-calculator.html#logic",
    "relatedWork": []
  },
  "publishedAt": "2026-07-18T00:00Z"
}