BASICS/THE COMMON CORE - Module 13

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By positioning the cursor (arrow) on a word underlined in the text, you can read its translation into Italian.

THE SHIP’S MOTIONS

A ship at sea has six degrees of freedom,

• rolling: a ship is said to be rolling when the bow and stern rise and fall with the oncoming waves.
  
  
  
  
• pitching: a ship is said to be pitching when the port and starboard sides rise and fall with waves coming from abeam.
  
  
  
  
• heaving: a ship is said to be heaving when the whole ship rises bodily and then sinks into the trough of the wave.
  
  
  
  
• yawing: a ship is said to be yawing when her bow is pushed to port and then to starboard.
  
  
  
  
• swaying: a ship is said to be swaying when the whole ship moves bodily first to port and then to starboard.
  
  
  
  
• surging: a ship is said to be surging when she is pushed forward by the waves and seems to move backwards when she falls back into the trough.
  
  
  
  

Of these motions. only rolling can be effectively reduced .by means of a stabilising system that provides an opposite force to that attempting to roll the ship , i.e by fitting fixed bilge keels, fin stabilisers or anti-rolling tanks.

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