What do two short horn blast from an approaching boat mean?

Answer 1

4 short blasts are the letter H is morse. On the River Clyde in Scotland a local bye law allows it to be signalled by a vessel going astern from a berth, generally a paddle steamer, indicating that it is going astern, it has difficulty in manoeuvring and warning other vessels to keep clear.

Answer 2

US_Inland_Rules:">US Inland Rules:

2 short blasts on a horn on a marine vessel while underway means that you intend to go to your own port "left" side to pass another vessel from head on or from the stern as in passing up or overtaking that other vessel situation. This is called the 2 whistle side. It's the opposite of the one whistle side which is the way you drive a car in America. When you overtake a car on the road you are passing him on the two whistle side. Ha!!! I would not recommend that you ever try to pass another vehicle on the 2 whistle side in a head on situation.

by: Capt. J.L.Lee

Rule 34 (a) -- When 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 manouvering 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 [left] side";

-- two short blasts to mean "I intend to leave you on my starboard [right] side"; and

-- three short blasts to mean "I am operating astern [reverse] propulsion."

(ii) upon hearing the one or two blast signal of the other shall, if in agreement, sound the same whistle signal and take steps necessary to effect a safe passing. If, however, from any cause, the vessel doubts the safety of the proposed maneuver, she shall sound the danger signal specified in paragraph (d) [five short and rapid blasts] of this Rule and each vessel shall take appropriate precautionary action until a safe passing agreement is made.

(c) When in sight of one another:

(i) a power-driven vessel intending to overtake another power-driven vessel shall indicate her intention by the following signals on her whistle:

-- one short blast to mean "I intend to overtake you on your starboard [right] side";

-- two blasts to mean "I intend to overtake you on your port [left] side"; and

(ii) the power-driven vessel about to be overtaken shall, if in agreement, sound a similar sound signal. If in doubt she shall sound the danger signal prescribed in paragraph (d) [five short rapid blasts].

International Rules:The International Regulations for the Prevention of Collision at Sea (COLREGS)

Rule 34 (a) -- When vessels are in sight of one another, a power-driven vessel underway, when manouvering 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 [right]";

-- two short blasts to mean "I am altering my course to port [left]";

-- three short blasts to mean "I am operating astern [reverse] propulsion."

(c) -- When in sight of one another in a narrow channel or fairway:

(i) a vessel intending to overtake another shall in compliance with rule 9(e)(i) indicate her intention by the following signals on her whistle:

-- two prolonged blasts followed by one short blast to mean "I intend to overtake you on your starboard [right] side";

-- two prolonged blasts followed by two short blasts to mean "I intend to overtake you on your port [left] side."

(ii) a vessel about to be overtaken when acting in accordance with Rule 9(e)(i) shall indicate her agreement by the following signal on her whistle:

-- one prolonged, one short, one prolonged, and one short blast, in that order.

Here's an example 'conversation' for the same situation in the two different 'languages':

US Inland

Vessel A -- "Short - Short" (I propose overtaking you on your port [left])

Vessel B -- "Five rapid blasts" (danger)

Vessel A -- "Short" (I propose overtaking you on your starboard [right])

Vessel B -- "Short" (I agree to be overtaken on my starboard [right])

International

Vessel A -- "Prolonged - Prolonged - Short - Short" (I intend to overtake on your port)

Vessel B -- "Five rapid blasts" (danger)

Vessel A -- "Prolonged - Prolonged - Short" (I intend to overtake you on your starboard)

Vessel B -- "Prolonged - Short - Prolonged - Short" (I agree to be overtaken)

Note that in many cases these arrangements are made via radio and the helmsmen will many times use the terms "one whistle" which is passing with the other vessel on your starboard (right) side, or "two whistles" which is passing with the other vessel on your port (left) side. One whistle is most common and generally expected unless circumstances dictate that two whistles is more appropriate.

Answer 3

The boat honking is intending to turn to port - its left.

Answer 4

Going to port