Horn(whistle)signals.
In International waters, the signals are to indicate 'actions'.
Example: 1 short blast means "I am altering my course to starboard". 2 short blasts means "I am altering my course to port".
In Inland waters, the signals are to indicate 'intentions' and must be answered by the same signal, prior to executing the maneuver.
Example: 1 blast means "I intend to overtake you on your starboard side". If the overtaken vessel agrees, they answer with the same signal. If the overtaken vessel does not agree, or considers the intended action dangerous they sound the danger signal, at least 5 short and rapid blasts.
One prolonged blast(4 to 6 seconds) means "I am leaving my slip or berth"
Three short blasts (about 1 second each) means "I am operating astern propulsion".
Larry H
In International waters, the signals are to indicate 'actions'.
Example: 1 short blast means "I am altering my course to starboard". 2 short blasts means "I am altering my course to port".
In Inland waters, the signals are to indicate 'intentions' and must be answered by the same signal, prior to executing the maneuver.
Example: 1 blast means "I intend to overtake you on your starboard side". If the overtaken vessel agrees, they answer with the same signal. If the overtaken vessel does not agree, or considers the intended action dangerous they sound the danger signal, at least 5 short and rapid blasts.
One prolonged blast(4 to 6 seconds) means "I am leaving my slip or berth"
Three short blasts (about 1 second each) means "I am operating astern propulsion".
Larry H