Equipment Number (IACS UR A1)
Anchor + chain sizing starts from the Equipment Number. IACS UR A1 combines displacement, side projected area and tier-level superstructure areas.
Equipment Number (EN)
3,327–
Formula, assumptions, and limits
The EN governs required mass of each bower anchor, chain diameter, chain length, and windlass torque per IACS UR A1 Table 1.
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| Ship displacement at SLWL | t | hydrostatic table | |
| Effective height × beam (hull+superstructure) | m² | GA plan | |
| Sum of tier-level superstructure areas | m² | GA plan | |
| Side-projected area above SLWL | m² | GA plan | |
| Equipment number | - | result |