Fog, anchored or aground, International and Inland
Anchored vessel's warning
Warns an approaching vessel of her position and the possibility of collision.
One short blast, then one prolonged blast, then one short blast
Who sounds it
A vessel at anchor, to warn an approaching vessel. Optional.
How it's sounded
Short blast: about 1 second (Rule 32(b)). Prolonged blast: 4 to 6 seconds (Rule 32(c)); 5 seconds is used here. 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
Optional and on top of the bell. Short, long, short.
More in fog, anchored or aground
- At anchor, under 100 metersInternational and Inlandrapid ringing of the bell
- At anchor, 100 meters or moreInternational and Inlandrapid ringing of the bell, then rapid ringing of the gong
- Aground, under 100 metersInternational and Inlandthree bell strokes, then rapid ringing of the bell, then three bell strokes
- Aground, 100 meters or moreInternational and Inlandthree bell strokes, then rapid ringing of the bell, then three bell strokes, then rapid ringing of the gong
Study more
See every sound signal, try the free Rules of the Road practice test, or read who gives way, and how Inland differs.
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