At one time the internationally agreed wireless distress call made by a ship requiring help at sea. It came into force on 1 July 1908 and is still one of the distress signals which can be used by a vessel requiring urgent assistance. The three letters were chosen because they were easy to read and make in Morse code—three dots, three dashes, three dots—but they did not stand for ‘Save Our Souls’, as is often thought. The first ‘SOS’ to be broadcast was in August 1909 when the American steamer Azaoahoe was disabled with a broken propeller shaft. See also global maritime distress and safety system; mayday; signals at sea.
Subjects: Maritime History.