Meeting and crossing, International and Inland
Operating astern propulsion
I am operating astern propulsion.
Three short blasts
Who sounds it
International: power-driven vessel underway, in sight of another vessel. Inland: power-driven vessels in sight, meeting or crossing within half a mile.
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
It means the engines are going astern. It doesn't promise the vessel is moving astern.
More in meeting and crossing
- Altering course to starboardInternationalone short blast
- Altering course to portInternationaltwo short blasts
- Proposing a port-to-port passInlandone short blast
- Proposing a starboard-to-starboard passInlandtwo short blasts
- Agreeing to a port-to-port passInlandone short blast
- Agreeing to a starboard-to-starboard passInlandtwo short blasts
- Passing agreed by radioInlandNo set pattern
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
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