Listening to the audio, the pilot first says, "We've experienced an engine failure, need a turn." ATC does not respond, so he calls again and says "Mayday" in order to unequivocally get their attention.
There are actually two different emergency calls. There is "mayday", and there is "pan-pan", which is a less urgent version of "mayday", but that is hardly ever used.
There are actually two different emergency calls. There is "mayday", and there is "pan-pan", which is a less urgent version of "mayday", but that is hardly ever used.