Recently I attended a 1-day course to obtain my Short Range Certificate (SRC), which is the radio operator qualification which authorises the holder to operate a VHF Radiotelephone fitted with Digital Selective Calling (DSC) on board any British vessel which is voluntarily fitted with radio equipment. The most important thing that you learn on such a course is when and how to send a Mayday message.
Mayday is an emergency code word used when sending a voice distress message. Why Mayday and not Juneday, or Aprilday? Well Mayday is derives from the French m’aider – help me (or more fully venez m’aider – come help me). The use of Mayday as an emergency code word was not a French imposition on the rest of the world but was suggested by a radio officer at Croydon Airport, which was London’s main airport before WWII.
A Mayday distress message should only be sent when the vessel or a person on board is in “grave and imminent danger”. Examples of “grave and imminent danger” in which a mayday call would be appropriate include fire, explosion, or sinking . If this is not the case then a Pan-Pan message should be sent, which indicates that there is a state of urgency but there is no immediate danger to anyone’s life or to the vessel itself. I suspect that in many cases when, for example a vessel is damaged and taking on water, most people don’t have time to consider the semantic differences between “urgent” and “grave and imminent” and just send a Mayday anyway before urgent becomes grave and imminent!
Voice Mayday distress messages are usually sent on channel 16. On boats fitted with Digital Selective Calling (DSC) a digital message (a bit like a pre-formatted text message) can be sent by pressing a distress button on the radio. The advantage of a DSC message is that it can automatically send information about a vessel’s position and the nature of the distress. However, a DSC message should always be followed by a voice Mayday so that vessels not fitted with DSC can hear it and to allow more detailed information about the nature of the distress to be transmitted.
Mayday messages are intended for reception by all vessels and the Coastguard. The Coastguard are responsible for co-ordinating the response to Maydays and can instigate the launch of lifeboats and search-and-rescue helicopters. Other boats in the vicinity are required to divert to assist the vessel that is broadcasting the Mayday. Only the Coastguard should respond to a Mayday. If a vessel hears a Mayday but it is not acknowledged by the Coastguard within 2 minutes, the vessel receiving the mayday call should attempt to contact the coastguard on behalf of the mayday vessel by broadcasting a mayday relay on their behalf.
A useful mnemonic to remember when sending a Mayday is MIPDANIO:
- Mayday (spoken word Mayday – 3 times)
- Identity (Vessel’s name + MMSI – 3 times)
- Position (Latitude/Longitude or Range/Bearing)
- Distress (Nature of emergency)
- Assistance (Required)
- Number (Persons onboard)
- Information (Any other relevant information)
- Over
Here is an example:
- Mayday, Mayday, Mayday, this is Yacht Calamity, Calamity, Calamity MMSI 230123456
- Mayday Yacht Calamity
- My position is fifty six degrees forty six minutes North, zero zero one degrees seventeen minutes West
- Swamped in rough sea and sinking
- I require immediate assistance
- Five adults and three children on board
- Abandoning to life-raft
- Over
I hope that I never have to send such a message but at least if I do I know how to!
One last thing, in films when people use 2-way radios they often sign off by saying “Over and Out” when they just mean “Out”. In radio procedure Over means “I have finished talking and I am listening for your reply” - short for “Over to you” – and Out means “I have finished talking to you and do not expect a reply”. So “Over and Out” means “I am expecting you to reply but will not listen to it”!
