Rules of the Road
Sound and light signals
Rule 34
Maneuvering and Warning Signals
International (Signals of Action)
(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 that maneuver by the following signals on her whistle.
-One short blast to mean "I AM altering my course to starboard";
-Two short blasts to mean "I AM altering my course to port";
-Three short blasts to mean "I AM operating astern propulsion".
Inland (Signals of intent)
(a) When a power driven vessels are in sight of one another and meeting or crossing at a distance within half a mile of each other, each vessel underway, when maneuvering as authorized or required by these rules:
(i) Shall indicate that maneuver by the following signals on her whistle: one short blast to mean "I intend to leave you on my port side" (turning to starboard.); two short blast to mean "I intend to leave you on my starboard" (turning to port); and three short blasts to mean "I amoperating astern propulsion"(This is the ONLY action in Inland)
Read more: What_do_two_short_horn_blasts_from_another_vessel_mean_in_a_meeting_situation
They are indicating a dangerous situation exists
They intend to pass starboard side to starboard side.
Two short horn blasts from another vessel typically indicate that the vessel is maneuvering to overtake or pass you on your port (left) side. This is a signal used to communicate intentions between vessels to ensure safe navigation and avoid collisions. It’s important to respond appropriately by maintaining your course and speed, allowing the overtaking vessel to pass safely.
Means it's about to turn to port.
Pilot vessel engaged in pilotage duties
Five short blasts on a horn in boating typically signal a warning or indicate that a vessel is unsure of another vessel's intentions, often in situations of restricted visibility or when navigating in close quarters. It can also mean that a vessel is backing up or has an emergency situation. This sound signal is part of the International Regulations for Preventing Collisions at Sea (COLREGs) and is important for maintaining safety on the water.
They are indicating dangerous
When leaving the dock, a vessel typically uses two short horn blasts. This is a standard maritime signal indicating to others that the vessel is departing. However, specific regulations may vary based on local maritime laws or the type of vessel, so it's important to be aware of any regional differences.
A vessel that is backing up typically uses a series of short blasts on its horn to alert other boats of its intention to maneuver in reverse. This sound signal consists of three short blasts, which indicate that the vessel is preparing to move backward. This is part of the International Regulations for Preventing Collisions at Sea (COLREGs) to ensure safety on the water.
Five short horn blasts from another boat on the water usually means danger. It could mean they have doubt in the message they had received from you, whether they did not hear it or did not understand. It can also be used to signal that the boat driver is confused about who has the right away. It is a signal to alert another vessel that you are unsure of its intentions, or doubt whether you are taking enough action to avoid a collision.
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?
Six blasts of a ship's horn does not seem to have a meaning. Five blasts will mean that you are possibly too close to another ship.