Sea cargo reference
Specialized
One cargo, one kind of hull. The notes below cover the cargo, the way the hull is arranged, and the limit that puts a ship in this class.
- Ship's gear
- Purpose-built handling equipment
- How capacity is counted
- Varies entirely by trade
- Usual size
- Purpose-built rather than standardised
- Cargo type
- Trade-specific
Specialised ships
Some cargo cannot be poured, pumped or boxed. These ships exist for those trades. Each one is drawn around a single cargo, not for general work.
The gear shows the trade: derricks rated in hundreds of tonnes, a stern ramp for rolling cargo, ventilated pens on several decks for livestock, or a plant that holds a whole hold at a set temperature.
The market is narrower than general tonnage, so ships are harder to find and the rate is less fluid. For the cargo they are built for, there is usually no other practical ship.
Cargo on board
How the hull is arranged
- Hull and gear are drawn around one cargo, not around general trade.
- The handling fit matches the trade: heavy-lift derricks, stern or side ramps, ventilation, or a refrigeration plant.
- The structure is strengthened where that cargo needs it, for point loads, vehicle decks, or several tween decks.
Why this trade uses it
- Takes cargo a general ship cannot carry safely or at a workable cost.
- Built-in gear keeps port time short where the shore has little equipment.
- For many of these trades it is the only practical ship.
Settle these points before you fix
- The trade is narrow, so ships are scarce and the rate is less competitive than open-market tonnage.
- The return voyage is often in ballast, because the special fit has nothing to load home.
- Many of these trades add their own rules on top of ordinary cargo law.