Um chamado de MayDay é feito em situação de:

Texto 1

Mayday Call

If a boat or a member of a crew is in danger do the following:

• ⋅ Press the alarm signal, if so equipped, on the transmitter for 30 to 60 seconds. This will alert people that a distress call is going to be made.
  
  
• ⋅ Say Mayday three times. Give the following:
  --Name of your boat
  --Report your position by giving latitude and longitude or distance and direction from a known object on a chart.
  --Describe your boat and number of people on board.
  --Describe the situation
  (http://www.sailingusa.info/sailing_safety.htm)