It means "Man overboard".
Note:
1 long blast = 5 or 6 seconds
1 short blast = 1 or 2 seconds
Three short blasts means "My engines are going Astern". (It doesn't necessarily mean that the ship itself is going astern).
International and Inland Navigational rules. Sound and Light Signals.
Rule 34
Maneuvering Signals(a) When vessels are in sight of one another, a power driven vessel underway, when maneuvering as authorized or required by these Rules, shall indicate than maneuver by the following signals on her whistle: -Three short blasts to mean "I am operating astern propulsion".
Rules of the Road
Sound & light signals
Rule 34 Maneuvering Signals and warning signals
(d) When vessels in sight of one another are approaching each other and from any cause either vessel fails to understand the intentions or action of the other to avoid collision, the vessel in doubt shall immediately indicate such doubt by giving at least 5 short and rapid blast of the whistle. Such signal maybe supplemented by a light signal of at least five short and rapid flashes.
you are altering your course to starboard
gat out of my way
They are indicating a dangerous situation exists
5 short blasts is a signal warning of imminent danger (or disagreement).
When two boats approach each other, they use horn blasts to signal the other about their intentions when it comes to moving to avoid collision. 5 short blasts indicates that the signaling boat is unsure about what the other boat is doing.
5 (or more) short blasts is the boating DANGER signal. It is mainly used when two vessels are approaching each other and the intent of the other vessel is unknown and/or may be dangerous to either vessel. A prudent captain will immediately slow down or stop when upon hearing this signal and take appropriate action.
5 (or more) short blasts is the boating DANGER signal. It is mainly used when two vessels are approaching each other and the intent of the other vessel is unknown and/or may be dangerous to either vessel. A prudent captain will immediately slow down or stop when upon hearing this signal and take appropriate action.
NASBLA Standard: 2.1 Resource: Federal Requirements and Safety Tips p.11 Course Location: p. 5Which of the following is a feature of a Type IV PFD?
5 short blasts.
Usually the tug towing the barge will sound it's horn or whistle. Most barges are unmanned. 5 or more short blasts of the ships whistle is the danger signal. If you hear this while boating you are likely in the way or crossing the path of the tug and tow, and there is risk of collision. Tugs with tows are much less maneuverable than a small boat and usually must stay in the dredged navigation channel.
they are indicating a dangerous situation exist
In the Navy, it means there is an eminent collision.With all due respect, this is an incorrect answer.From the 1972 Convention of International Regulations for Preventing Collisions at Sea.InternationalSounds and Light signalsRule 34(D) When vessels are in sight of one another and from any cause either vessels fails to understand the intentions or actions of the other, or is in doubt whether sufficient action is being taken by the other to avoid collision, the vessel in doubt SHALL immediately indicate the doubt by giving at least 5 short and rapid blasts of the whistle.