Influenced by the water depth of ship sea trial area, velocity measurement of deep-draft large-scale ship should be shallow-water corrected with proper method.

受实船试航水域水深的影响，对于深吃水的大型船舶航速测量结果必须采用适当的方法进行航速的浅水修正。

youdao

The captain proceeded in the fjords at very slow speed, barely moving forward, by lowering an anchor from the bow to a depth greater than the hull of the ship.

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