COLREGs Overtaking Rule

The COLREGs, 1972 are internationally agreed rules for preventing collisions between vessels at sea. Under Rule 13, a vessel overtaking another becomes the give-way vessel and must keep out of the way of the vessel being overtaken.

When a vessel is overtaking

A vessel is deemed to be overtaking when it approaches another vessel from a direction more than 22.5 degrees abaft the beam. At night, this means that it would see only the other vessel's sternlight, but neither sidelight.

• If there is doubt whether an overtaking situation exists, the approaching vessel must assume that it is overtaking and act accordingly.

Duty of the overtaking vessel

Notwithstanding the other steering and sailing rules in Rules 4-18, the overtaking vessel must keep out of the way of the vessel being overtaken. As the give-way vessel, it should take early and substantial action to remain well clear; Rule 13 does not prescribe that it must pass on a particular side.

How long the duty continues

A later change in the bearing between the vessels does not convert the overtaking vessel into a crossing vessel or end its responsibility. The duty continues until the overtaking vessel is finally past and clear of the other vessel.

• The vessel being overtaken ordinarily acts as the stand-on vessel under Rule 17, while retaining authority to act when necessary to avoid collision.