Chapter 2: Navigation in Ice

2.1 General

Ice is an obstacle to any ship, even an icebreaker, and the inexperienced Navigation Officer is advised to develop a healthy respect for the latent power and strength of ice in all its forms. However, it is quite possible, and continues to be proven so, for well-found ships in capable hands to navigate successfully through ice-covered waters.

The first principle of successful ice navigation is to maintain freedom of manoeuvre. Once a ship becomes trapped, the vessel goes wherever the ice goes. Ice navigation requires great patience and can be a tiring business with or without icebreaker escort. The long way round a difficult ice area whose limits are known is often the fastest and safest way to port, or to the open sea.

Experience has proven that in ice of higher concentrations, three basic ship handling rules apply:

  • keep moving - even very slowly, but keep moving;
  • try to work with the ice movement, and not against it; and
  • excessive speed means ice damage.


Excessive speed is the major cause of damage to ships by ice.

A glossary of ice terminology and descriptions is contained in Annex A.

Ice Navigation in Canadian Waters