Last updated: 2026-04-14Contact: developer@captaincalc.com.tr
Reference basis: IMO/COLREG/STCW concepts, nautical practice, approved ship documents, and CaptainCalc calculation notes. Always verify operational decisions with official sources.
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FWA & DWA Calculator
Calculate Fresh Water Allowance (FWA) and Dock Water Allowance (DWA) for load-line operations.
Formula reference
FWA (mm) = W / (4 × TPCSW)
DWA (mm) = FWA × (1025 − ρdock) / 25
Positive DWA = add to load-line (load deeper). Negative = load less.
⚠ Cross-check with vessel stability booklet and port authority regulations.
DWA (mm) = FWA × (1025 − ρdock) / 25
Positive DWA = add to load-line (load deeper). Negative = load less.
⚠ Cross-check with vessel stability booklet and port authority regulations.
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