Deadweight tonnage: carrying weight, not cargo alone

Key takeaways

• Cargo shares the weight allowance with fuel, water and other items.
• Port, load-line and vessel constraints require a separate check.

Distinguish two capacity questions

The first question concerns the vessel's stated deadweight. The second concerns how much of the applicable weight allowance remains for cargo on this voyage. Those questions need different inputs.

ILLUSTRATIVE — invented teaching inputs. Assume a relevant weight allowance of 50,000 tonnes and other onboard weights of 3,000 tonnes. Simplified cargo balance = 50,000 − 3,000 = 47,000 tonnes, before further constraints.

1. Obtain the vessel's relevant loading particulars.
2. Account for non-cargo weights on the proposed voyage.
3. Have the appropriate technical team confirm the permissible cargo plan.

The arithmetic only illustrates why a deadweight figure cannot be copied directly into a cargo nomination. It does not establish a safe loading condition or account for every operational restriction.

Common mistakes

Do not confuse deadweight with gross tonnage, which is a different measure. Avoid treating an illustrative capacity subtraction as a substitute for approved loading information and voyage-specific checks.

Where Zeaclub fits

Zeaclub offers digitalised procedures across the voyage workflow.

Zeaclub supports agentic, AI-assisted operations with a human in control.

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