Intact stability weather criterion (IS Code §2.3) - the dead-ship side-wind + roll assessment that governs many passenger and offshore vessels.
Formula
$$ l_{w1} = \frac{P \cdot A \cdot Z}{1000,g,\Delta}, \quad l_{w2} = 1.5 \cdot l_{w1} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $P$ | Wind pressure | N/m² | IS Code 504 N/m² default |
| $A$ | Lateral wind area | m² | GA + profile |
| $Z$ | Centroid above WL/2 | m | profile drawing |
| $\Delta$ | Displacement | t | loading computer |
Sources
- IMO 2008 IS Code §2.3.