Meeting and crossing, International

Altering course to port

I am altering my course to port.

Two short blasts

Press play. One signal at a time.

  1. Altering course to portInternational

    "I am altering my course to port."

    Rule 34(a)

Who sounds it

Power-driven vessel underway, in sight of another vessel, when maneuvering.

How it's sounded

Short blast: about 1 second (Rule 32(b)). The rule sets no gap between blasts. 1 second is used here so the blasts stay distinct.

A short blast is about 1 second. A prolonged blast is 4 to 6 seconds. Clips use 1 and 5 seconds.

Worth remembering

Same two blasts as Inland, different meaning. Check which rules apply.

The same sound elsewhere

These use the same pattern, so the rules you’re under and the situation decide what it means.

More in meeting and crossing

Study more

See every sound signal, try the free Rules of the Road practice test, or read who gives way, and how Inland differs.

Learn the whole set

Helm drills every signal with flashcards and spaced review, on the web and iPhone.

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Sources

Helm is an independent study aid, not affiliated with or endorsed by the U.S. Coast Guard or the National Maritime Center. This page is for study, not navigation guidance or legal advice. Check the current rules before you rely on anything here.