HomeCalculatorsNatural Roll Period - Rational Formula

Natural Roll Period - Rational Formula

Natural rolling period from GM and ship beam - the Weiss formula used for synchronous rolling check and inclining verification.

RollSeakeepingWeiss
Natural roll period
26.3s
Formula, assumptions, and limits

C ≈ 0.44 for passenger ships, 0.40–0.43 cargo, 0.36 fishing vessels. Check against IMO MSC.1/Circ.1228 - if T_r too close to wave encounter period → risk of synchronous roll.

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SymbolMeaningUnitSource
Metacentric heightminclining test
Breadth (moulded)mship particulars
Roll-radius coefficient - Weiss formula