What the SOS Distress Signal Stands For

Today I found out what SOS stands for.

It is commonly held that “SOS” is an acronym for “Save Our Ship” and thus often written “S.O.S.”  In truth, SOS is not an acronym for anything, which is why it is incorrect to put full stops between each letter.

So why was SOS chosen to signify a distress signal?  The thought was that SOS- in Morse code signified by three dots, three dashes, then three dots- could not be misinterpreted as being a message for anything else.  Further, being sent together as one string (with no stops), it could be sent very quickly and needs very little power to transmit.

So, despite what you might have read elsewhere, as the 1918 Marconi Yearbook of Wireless Telegraphy and Telephony notes, “This signal [SOS] was adopted simply on account of its easy radiation and its unmistakable character.  There is no special significance in the letters themselves…”

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Bonus Facts:

  • The SOS signal was created and adopted as the universal international distress signal at the 1906 Berlin Radiotelegraphic Conference.
  • In 1909, T.D. Haubner of the SS Arapahoe became the first person to use the SOS distress signal call.  The ship he worked on had lost its screw near the Diamond Shoals which are also known as the “Graveyard of the Atlantic”.  Interestingly, a few months later Haubner, still working on the SS Arapahoe, received the world’s second SOS call; this one sent from the SS Iroquois.  So he was the first sender and the second receiver.
  • The signal “SSS” was adopted during WWII when the emergency was caused by a submarine attack.  This was to let any potential rescuing ships know there was a hostile submarine in the region.
  • The creator of the S.O.S pads wife thought that the SOS signal stood for “Save Our Ships”, which inspired her to name her husband’s cleaning pads S.O.S, standing for “Save Our Saucepans“.
  • The SOS standard signal for distress was preceded by the standard “CQD” signal which meant literally: CQ: general call or “all stations”; D: Distress.
  • The Titanic’s radio officer Jack Phillips first used the old standard “CQD”  to call for help.  He transmitted “CQD” six times followed by the Titanic’s call letters “MGY”.  He later interspersed “SOS” in with the “CQD” messages, at the suggestion of junior radio officer Harold Bride.
  • Interestingly Marconi, of the Marconi Company who had originally suggested “CQD” for a distress signal, was waiting in New York to return to England on the Titanic.
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  • Very interesting. I always thought it stood for Save Our Ship. I never even considered Morse code origins though.

  • Damn, I always assumed it stood for Save Our Souls. Makes sense…

  • swedishhighball

    SOS stands for nothing. It was used by code senders because it was the easiest
    three letters to send. It consistes of 3 dots, three dashes, three dots.

    s o s

  • swedishhighball

    On the above posting it looks like three dots and one dash. O in morse code is three dashes.

    … – – -…

  • Alright; I need to clear some things up here.
    The Cunard liner SS Slovenia was the first ship to send SOS. The Arapahoe was the first American ship to send SOS.
    Harold Bride was the assistant wireless operator on Titanic, not Carpathia.
    And CQ was already in use as an “all stations” call, Marconi simply added the D to make the call a general emergency call, D signifying distress.
    But not bad for a college boy I guess.

  • I always thought it meant Stranded On Shore

  • Harold Bride was the other wireless operator in Titanic, not SS Carpathia as stated.

    • Daven Hiskey

      @Patrick: Correct. Thanks for catching that. 🙂 The confusion was that after being rescued by the Carpathia, Bride temporarily became one of the wireless operators aboard the Carpathia as they had a lot of things to transmit and needed the extra help.

  • Stuck Out Stranded

    Was my original thought. For 17 years. :p

  • Peter Wood Jenkins

    It\s well known to be an Acronym, for Save Our Souls. So nothing will change that for me.

    Speaking as one who gave out an S.O.S. when our yacht got into trouble off of England, .

    To say it stands for nothing is daft, it’s a distress signal, and it’s only given when you get in dire danger.

    So it would be better if you re learn something today yes it is an acronym .

    • It’s not. I have known that forever and it’s well documented. “Save Our Souls” would be a silly call anyway. As the article stated, it’s its morse structure that makes it effective.

  • Great article about SOS. I was a ship’s radio operator for 30 years and morse code was our language.

    It certainly has an umistakable character. It is all run as one character; ditditditdahdahdahditditdit & any ship’s operator could pick it out anywhere.

    Morse came to an end aroundabout 1991-92 for commercial use but I still have a listen every so often in the internet.

    Thanks again for that article – well done.

  • When and why did SOS become Save Our Souls?

  • Forget all this non sense, SOS means Shi t out of Shi t, or as we currently know it SOL

  • What I’m wondering is… how was morse code determined? Could SOS have still originally meant something, and morse code was made to fit it? (must go and find morse code now to see what the pattern is!)

  • You said “it is incorrect to put full stops between each letter”. But how about putting periods between each letter? 🙂