COLREGs Rule 11: Application of Section II — Explained

Rule 11 says the rules in Section II of Part B (Rules 12 to 18: sailing vessels, overtaking, head-on, crossing, give-way, stand-on and the vessel hierarchy) apply only to vessels in sight of one another.

What Rule 11 says

Rules 12 to 18 apply to vessels in sight of one another, meaning one can be seen visually from the other.

This is a plain-English summary, not the official wording. For the exact text, see the IMO convention. In UK waters the rules are given legal force by the Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations.

What it means on a yacht

If you can only 'see' a vessel on radar or AIS in fog, there is no stand-on or give-way vessel. Rule 19 applies instead, and both vessels must act.

Practise it

Test yourself on who gives way in the free COLREGs trainer, or print the rules of the road cheat sheets for the chart table.

Other rules in Part B

Rule 4: Application of Section I
Rule 5: Look-out
Rule 6: Safe speed
Rule 7: Risk of collision
Rule 8: Action to avoid collision
Rule 9: Narrow channels
Rule 10: Traffic separation schemes
Rule 12: Sailing vessels
Rule 13: Overtaking
Rule 14: Head-on situation
Rule 15: Crossing situation
Rule 16: Action by give-way vessel
Rule 17: Action by stand-on vessel
Rule 18: Responsibilities between vessels
Rule 19: Conduct of vessels in restricted visibility