Under restricted visibility, a power-driven vessel must sound one prolonged blast every two minutes. This signal is intended to alert other vessels in the area of its presence. Additionally, vessels may also be required to sound other signals depending on their specific maneuvers or circumstances.
Sailboat
One prolonged blast followed two short blasts, every two minutes, not to exceed two minutes. Rule 35-Sound Signals in restricted visibility.
In restricted visibility, a power-driven vessel under way is required to sound one prolonged blast followed by two short blasts every two minutes. This signal helps to indicate the vessel's presence to other nearby vessels in low visibility conditions. The prolonged blast lasts for about four to six seconds, while the short blasts are approximately one second each.
One prolonged and two short blasts is 'D' in Morse signals. It is a signal to be used in restricted visibility by a vessel not under command[NUC], a vessel restricted in her ability to manoeuvre[RAM], a vessel constrained by her draught, a sailing vessel, a vessel engaged in fishing and a vessel engaged in towing or pushing another vessel.
When visibility is very limited, such as in heavy fog, boaters must give an audible signal to others in the area. For a sailboat the signal is one prolonged blast plus two short blasts every two minutes.
Rules of the Road, Rule 35, Sound Signals in Restricted Visibility. (B) A power driven vessel underway but stopped and making no way through the water shall sound at intervals of not more than two minutes, two prolonged blasts in succession with an interval of about two seconds between them.
In reduced visibility, a power-driven vessel underway is required to sound one prolonged blast followed by two short blasts every two minutes. This signal indicates its presence to other vessels in the area. The prolonged blast lasts about four to six seconds, while the short blasts last about one second each. This signaling helps to prevent collisions in situations where visibility is limited.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.
One prolonged blast plus two short blasts every two minutes. Explanation: Sound signals let other boaters know where you are located during periods of restricted visibility, such as extreme fog. If you hear the fog signal of a vessel you cannot see, slow to a minimum speed until you are sure there is not a risk of collision. One prolonged blast plus two short blasts at intervals of not more than two minutes is the signal used by sailing vessels.