IS Code - Severe-Wind & Rolling Criterion
Intact stability weather criterion (IS Code §2.3) - the dead-ship side-wind + roll assessment that governs many passenger and offshore vessels.
Steady wind heeling arm
0.030m
Gust heeling arm
0.045m
Screening
Likely compliant - verify area b ≥ area a
Formula, assumptions, and limits
IS Code 2008 §2.3: area b under GZ from angle of equilibrium to min(θ_c, 50°, flooding angle) must exceed area a to leeward of roll-back angle. This calc screens the heeling arms; full trapezoidal integration needed for compliance.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Wind pressure | N/m² | IS Code 504 N/m² default | |
| Lateral wind area | m² | GA + profile | |
| Centroid above WL/2 | m | profile drawing | |
| Displacement | t | loading computer |