Marine & Nautical

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Draft from Displacement

Depth of hull below waterline from displacement and waterplane area.

Formula

T = \frac{\Delta}{\rho\, A_w}

Variables

TDraft (m)

ΔDisplacement (kg)

ρWater density

A_wWaterplane area (m²)

Example

Heavier cargo increases draft — the ship sits lower in the water.

Did You Know?

The Plimsoll line painted on hulls marks the safe maximum draft in different waters and seasons.

marine draft ship

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