Responsibilities between vessels
In plain language
The pecking order: a power-driven vessel keeps clear of vessels not under command, restricted in ability to manoeuvre, engaged in fishing, and sailing vessels. A sailing vessel keeps clear of fishing vessels, RAM and NUC. A fishing vessel keeps clear of RAM and NUC.
Full text of Rule 18
Except where Rules 9, 10 and 13 otherwise require:
A power-driven vessel underway shall keep out of the way of:
a vessel not under command;
a vessel restricted in her ability to manoeuvre;
a vessel engaged in fishing;
a sailing vessel.
A sailing vessel underway shall keep out of the way of:
a vessel not under command;
a vessel restricted in her ability to manoeuvre;
a vessel engaged in fishing.
A vessel engaged in fishing when underway shall, so far as possible, keep out of the way of: a vessel not under command; a vessel restricted in her ability to manoeuvre.
Any vessel other than a vessel not under command or a vessel restricted in her ability to manoeuvre shall, if the circumstances of the case admit, avoid impeding the safe passage of a vessel constrained by her draught, exhibiting the signals in Rule 28.
A vessel constrained by her draught shall navigate with particular caution having full regard to her special condition.
A seaplane on the water shall, in general, keep well clear of all vessels and avoid impeding their navigation. In circumstances, however, where risk of collision exists, she shall comply with the Rules of this Part.
A WIG craft when taking-off, landing and in flight near the surface shall keep well clear of all other vessels and avoid impeding their navigation;
A WIG craft operating on the water surface shall comply with the Rules of this Part as a power-driven vessel.
Reproduced from the COLREGs 1972 (as amended) for study. Always verify against the official IMO publication.
Key points
- 1
Priority ladder: NUC → RAM → fishing → sailing → power-driven.
- 2
Seaplanes keep well clear of all vessels.
- 3
A vessel constrained by her draught shall navigate with particular caution.
- 4
Overtaking (Rule 13) overrides this hierarchy.