What does Mayday aviation mean?

Distress signal is an international radio distress signal. The word "Mayday" was originally the French word "m'aider" for "help me" (it is not used alone in standard French, but Venez m'aider or Aidez-moi is usually used), but it is pronounced as "Mayday" in English. Calling Mayday on the radio means encountering a real-time dangerous situation that threatens life.

Call for help three times in a row ("help, help, help") to avoid being heard, drowned by noise or confused with other communications. Usually ships or planes will use distress signals for help; Police and firefighters in some areas also use this call sign to ask their colleagues for help.

Extended data:

At sea, when the rescue center receives the distress signal, it may send planes or ships to the scene for search and rescue. Nearby ships may also be transferred to the site for assistance. Sending a distress signal in a radio call is the same as sending SOS in a radio telegram or dialing an emergency number on the ground. Sending false distress signals is a criminal offence in most places, because it may endanger the lives of rescuers and waste resources. In the United States, sending false distress signals is a violation of federal law, and can be sentenced to six years in prison and a fine of $250,000, so please use Mayday with caution!

Similarly, Pan Pan is often heard in aviation distress, from French panne:fault；; It is another kind of emergency signal, indicating that there is no important emergency on May day, not a fatal fault, but a fault that can be handled.

Baidu Encyclopedia-Mayday