Rule of Twelfths

The Rule of Twelfths is a rule of thumb for estimating the height of the tide at any given time. The rate of flow in a tide increases smoothly to a maximum halfway point between high and low tide, before smoothly decreasing to zero again. This is important when...

Navigation Rules/Rules of the Road

Pecking order of vessels. There is a basic order, in the navigation rules, that governs who stays out of the way of whom. Essentially, the hardest to maneuver vessels are stand-on while the easiest to maneuver vessels are give-way. In the following list vessels...