A ham radio club in New Jersey held a meeting one evening where they had a special speaker talking about distress communications. As I sat listening to the repeater and working one of the hams that had been at that meeting started calling “Mayday” just trying to be funny. Either the speaker missed a very important part of his subject or someone was not listening when he did. Others came on and they were all joking around about the whole thing when I broke in and warned them that what they were doing was inappropriate. (And just so you know I didn’t scold them or call them down I just explained why what they were doing was unwise – people make mistakes and we should be able to tell them politely.)
Distress calls are serious business. In the United States of America a false distress call can result in 6 years in a federal prison (the time has been decreased sense 1965) plus $250,000 in fines. On top of that some states, if they render state assistance, can charge the person making such a call for the cost to the state for responding and that can add up to several thousands of dollars.
That is enough threats now for some information about distress.
After Marconi revealed his invention to the world the shipping industry was quick to employ it on board their ships. Ships could communicate with land stations giving and receiving various bits of necessary information to improve the efficiency in transporting their load. The radio operators came from the most likely source, the land telegraph operators.
The railroad telegraphers and the message wiring companies had adopted a special code which was used to notify that this message was for everyone listing. It was CQ so when they went aboard ships they carried the same code. When in distress most operators would add a D to the end of CQ making it CQD. But there was no standard so others used DDD. There was some confusion so at the second Berlin Radiotelegraphic Conference 1906 the subject was discussed at length. The conference finally accepted that SOS would be the acceptable international distress calling signal.
Some think SOS was chosen to mean Save Our Soles, and others argue that it means Save Our Ship but the truth is it doesn’t mean either. The Marconi Yearbook of Wireless Telegraphy and Telephony, 1918 made it very clear with these words, “This signal [SOS] was adopted simply on account of its easy radiation and its unmistakable character. There is no special signification in the letter themselves, and it is entirely incorrect to put full stops between them (the three letters).” SOS is a single character not three separate letters (not … — … but …—…).
Voice communications became possible and this required a voice equivalent to the SOS signal. The French expression “M’aidez” (which means “come help me” though apparently not grammatically correct) was considered. The word took on a more English sound and thus became Mayday (one word).
If you are discussing a holiday which comes on the first of May on the radio I personally recommend not call it “May Day”. Someone who does not speak English may have no idea what you are saying but hear and recognize that word “Mayday”. Just don’t use those two words together on the radio unless there is a real distress.
Distress means eminent danger to life or property. My car won’t start and I need a tow is not a distress. My car is hanging over a cliff and may plunge over the edge at any time and I can’t get out is a distress.