HAM Radio 101

The Meaning and History of SOS

What does SOS stand for? It’s not “Save Our Ship” or “Save Our Souls” like you might think. Instead, the distress signal that originated in the maritime community is communication used specifically for ships, based on Morse Code, that is represented by three dots, three dashes, and three more dots.

Developed by Samuel Morse in 1835, Morse code’s dots and dashes signify letters of the alphabet and are used to communicate messages, such as SOS, by sending electric pulses. But SOS wasn’t the first recognized distress signal. Before SOS there was CQD, with the “CQ” translating to “general notice” and the “D” an abbreviation for “distress.”

However, CQD wasn’t a universal distress call. England used CQD, the U.S. Navy used NC (the International Code of Signals maritime distress flag signal), and Italy used SSSDD. The need for a common indicator of distress was real, and the mode of communication needed to fit for long- distance communications—instead of being limited to those within sight range.

The universal use of SOS was ratified at the 1906 Radiotelegraph Conference and went into effect in 1908. Its first documented use in the U.S. occurred in August 1909 when the SS Arapahoe lost power in the Graveyard of the Atlantic near Diamond Shoals. T.D. Haubner (also the recipient of the second documented SOS signal) sent the distress call, and the ship and crew were successfully rescued.

Today, SOS is not limited to telegraphs. It is a multi-faceted mode of messaging used to signal for help in various crisis situations—learn about ways to use it here. Long and short bursts of light from a flashlight, or the glint of sun off a mirror, have been used by climbers trapped on mountains to call for aid.

Large print letters written in the sand have saved the lives of shipwreck victims or those that drift too far while snorkeling. Even the Titanic captain signaled repeatedly to ask for aid with CQD as he sank to the ocean’s bottom with the ship.

Here are a few common signals:

  • SOS AAA – signals an attack by aircraft
  • SOS QQQ – signals an attack of an unknown raider
  • SOS RRR – signals an attack by a surface raider
  • SOS SSS – signals a submarine attack

Visit DX Engineering for the reference books and tech you need for Morse code messaging.


Leave a Reply