Sound Signals

 

 Commercial vessels use sound signals so listen out for them.  If you hear them you probably need to know the intentions of the vessel making them:

 

            short blast    =    1 blast         long blast    =     1 long blast


short blast          I am altering my course to STARBOARD

 

short blast short blast        I am altering my course to PORT

 

short blast short blast short blast        I am going ASTERN

 

short blast short blast short blast short blast   short blast        I am turning through 360 degrees to STARBOARD

 

short blast short blast short blast short blast   short blast short blast        I am turning through 360 degrees to PORT

 

short blast short blast short blast short blast short blast       I do not understand your intentions - keep clear - I doubt whether you are taking sufficient action to avoid a collision

 

long blast        I am about to get underway, enter the fairway or I am approaching a blind bend

 

long blast   short blast   short blast       I am unable to manoeuvre - not under command

 

long blast   long blast   short blast         I intend to overtake you on YOUR STARBOARD side

 

long blast   long blast   short blast   short blast        I intend to overtake you on YOUR PORT side

 

long blast   short blast   long blast   short blast        I agree to be overtaken

 

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