hull speed |

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no secret that tugboats aren’t designed for speed. They have deep, full-

displacement hulls. They are wide. Their diesel engines and gearboxes are

designed for torque and power, not speed. There is an engineering concept

governing hull speed that every naval architect is familiar with.

Hull speed equals roughly 1.34 times the square root of the waterline length.

For a vessel with a waterline length of 144 feet, the square root is 12. We

multiply 12 times 1.34, which gives us 16.08, or rounded off two decimal places,

16 knots. Now remember that this is a general engineering relationship. There

are vessels that defy it, such as destroyers and other very slender warships.

However, a tug without a tow making speed carves out a deep trough of a wave

A hullform vastly different than the