In May 2020, the pilot of Pakistan International Airlines Flight PK 8303 reported technical problems and uttered the dreaded “mayday” alert. “We have lost two engines. Mayday, mayday, mayday,” were the pilot’s last words, according to Business Insider. Ninety-seven people perished.
“Mayday!” is an international distress call used by airplane pilots, boat captains and some emergency response personnel. The U.S. Coast Guard deals with roughly 25,000 distress calls every year, some of which involve the “mayday” code.
The signal arose just after World War I, as air traffic between Britain and mainland Europe increased dramatically. All nearby nations needed an internationally understood signal that would alert authorities to urgent aircraft problems.
Why not just use the standard “SOS” call that navy captains used when they were in trouble? Well, ships communicated through telegraph using Morse code, and this technology made “SOS” (three dots, three dashes, three dots) unmistakable. By contrast, aircraft pilots used radio calls, and “SOS,” owing to its consonants, could be misheard as other letters, like “F.”
Frederick Stanley Mockford, a senior radio officer in London, was put in charge of finding an appropriate code word. He reasoned that because so much of the air traffic flew between Croydon and Le Bourget Airport in Paris, it might make sense to use a derivative of a French word.