Sound Signals At Sea

Vessels In Sight OF Each Other:

One Short Blast -
I am altering my course to starboard.

Two Short Blasts - -
I am altering my course to port.

Three Short Blasts - - -
My engines are running astern.

Five (or more) Short Blasts - - - - -
Your intentions are not understood. Keep clear.

Vessels In Restricted Visibility

One Long Blast ( Every 2 mins) ---
Power vessel underway and making way.

Two Long Blasts (Every 2 mins) --- ---
Power vessel stopped.

One Long & Two Short Blasts (Every 2 mins) --- - -
Vessels Under Sail also : Vessels fishing, towing, etc.

Morse Code 'B' (Every 2 mins) --- - - -
Vessel under tow (if manned).

Vessels At Anchor

Rapid ringing of bell for five seconds every minute

Vessel over 100m : Bell rung forward. Then gong rung rapidly aft for 5 seconds.

May Sound Morse Code 'R' (- --- -) to warn approaching vessel.

Vessels Aground

Three Rings Of Bell + Anchor Signal + Three Rings Of Bell

Vessels In A Narrow Channel

Two Long & One Short Blast --- --- -
I intend to overtake you on your starboard side.

Two Long & Two Short Blasts --- --- - -
I intend to overtake you on your port side.

Morse Code 'C' --- - --- -
I agree to be overtaken

One Long Blast ---
I am approaching a bend in the channel.

--- = 1 Long Blast - = 1 Short Blast