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Air draft
Distance from water to the highest point on a vessel or lowest point on a bridge span / From Wikipedia, the free encyclopedia
For other uses, see Draft (disambiguation).
Air draft (or air draught) is the distance from the surface of the water to the highest point on a vessel. This is similar to the deep draft of a vessel which is measured from the surface of the water to the deepest part of the hull below the surface. However, air draft is expressed as a height (positive upward), while deep draft is expressed as a depth (positive downward).[1][2]
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