RulesAtSea

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Meeting head-on

Reciprocal courses. Foundation level, about 3 min. COLREGs Rule 14.

The situation

Another power-driven vessel is approaching on a reciprocal course. The situation involves risk of collision, with open water on either side.

How should the two vessels pass?

  1. Alter to starboard: Pass port side to port side.
  2. Keep your present course: Wait for the other vessel to turn.
  3. Alter to port: Try to pass starboard side to starboard side.

Lookout: Check the other vessel’s aspect. At night, seeing both sidelights and a masthead light can help recognise a head-on situation.

The sound answer

Alter to starboard

Both power-driven vessels should alter course to starboard so they pass port side to port side. The other vessel’s matching action is explicitly authored in this replay.

Why the other options fall short

Keep your present course

Head-on action is a duty for both vessels. Waiting for the other vessel’s alteration leaves you on a collision course.

Alter to port

For this head-on situation, Rule 14 requires an alteration to starboard. A port alteration can conflict with the other vessel’s expected action.

Rule 14 · Head-on situation

When two power-driven vessels meet on reciprocal or nearly reciprocal courses so as to involve risk of collision, each alters course to starboard to pass on the port side of the other.

US Coast Guard · International Navigation Rules