Maritime glossary
Air Draught
The vertical distance from the waterline to the highest fixed point of a vessel, the constraint under bridges and cranes.
Definition
Air draught is the height of a vessel above the waterline, measured to the masthead or the highest fixed point. It is the mirror image of draught below the water and decides whether a ship can pass under a bridge or work under a shore crane. Air draught changes with loading: a ship in ballast sits higher and has a greater air draught than the same ship fully laden.
Worked example
An ultra-large container ship with an air draught near 73 m cannot pass under the old Bayonne Bridge clearance of 46 m, which is why the bridge was raised to 65 m for the New York and New Jersey terminals.
How Vessel Hunter uses Air Draught
For terminals and bridge-restricted ports, air draught is the dimension that decides the call. Vessel Hunter keeps it on the dossier alongside the underwater draught.
Related terms
- Draught
The vertical distance from the waterline to the deepest point of the hull, the constraint that decides which ports a loaded vessel can enter.
- LOALength Overall
The maximum length of a vessel from the foremost to the aftmost point, including any fixed projections.
- Beam
The widest point of a vessel, the constraining dimension for lock chambers, dry docks, and some terminals.
The bigger picture
Air Draught is one piece of the commercial maritime picture Vessel Hunter pulls together for shipyards, suppliers, service providers, and port agents. Every vessel record bundles AIS, ownership, inspections, dry-dock history, casualty record, classification status, and a verified contact for the operator decision-maker behind the ship, so the team that reaches out first wins the work.
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