Speaking of Narrow Channels – Sound Signals

My last post dealt with the “Back and Fill” maneuver or how to do a pivot turn in a narrow channel. As a general rule when you are operating in a narrow channel you are most likely in Inland Waterways and should understand the Inland Rules of the Road concerning maneuvering and sound signals.

Bell, horn and whistleEvery vessel is required to carry some kind of efficient sound producing device to signal their intentions as outlined below.

Vessels 39.4 feet (12 meters) or more in length are required to carry a whistle or horn. Vessels less than 39.4 feet (12 meters) in length (including PWCs) may carry a whistle or horn or some other means to make an efficient sound signal audible for 1/2 mile.

Vessels 65.6 feet (20 meters) or more in length are required to carry a whistle or horn and a bell that are audible for 1 mile. Please note that the bell is no longer required on a boat 12 meters or more but less than 20 meters in length.

Vessels are required to sound signals any time that they are in close quarters and risk of collision exists.

First we need to define certain sound signals that you may hear.

  • The term “short blast” means a blast of about one second.
  • The term “prolonged blast” means a blast of from four to six sconds.

The following signals are the only ones to be used to signal a vessel’s intentions ( inland rules only).

  • One short blast – I intend to change course to starboard.
  • Two short blasts – I intend to change course to port.
  • Three short blasts – I am operating astern propulsion (backing up).
  • Five or more short and rapid blasts – Danger or doubt signal (I don’t understand your intent).

The vessel about to be overtaken will, if in agreement, sound a similar sound signal. If in doubt, the vessel must sound the danger signal of at least five short, rapid blasts.

Note: Inland rules use sound signals to indicate intent to maneuver and a response should be received. In international rules the signals are given when the maneuver is being executed.

Vessels indicate their intention to maneuver by using sound signals. If you do not agree with or understand clearly what the other vessel’s intentions are, you should sound the danger or doubt signal (5 short, rapid blasts). Each vessel should then slow or stop until signals for safe passing are sounded, understood and agreed to.

The danger or doubt signal can also be used to tell another vessel that its action is dangerous. If a boat is backing up into an obstruction you would sound the danger signal to warn the operator.


Leave a comment

Filed under Boat Operation, Boating Safety, Navigation

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s