Mayday - MMSI and Position

Now we are in the new world of one Coastguard "call centre" I am very, very uneasy about giving anything but a lat and long.

The lat and long are for the Coastguard (as you say, they don't seem to be very good at dealing with any other form of position nowadays). The verbal description is for other nearby vessels.

Pete
 
can you, hand on heart, guarantee with absolute total and utter certainty that it will "do just fine" in the Maldives, or Corsica, or the Antarctic, or in the Red Sea, or via an HF call from the middle of the South Atlantic or where the initial DSC Mayday is followed up with a satellite phone call or ...

I do not sail in the Maldives, Corsica, the Antarctic, or the Red Sea. I do not have an HF radio or a satellite phone.

Pete
 
I do not sail in the Maldives, Corsica, the Antarctic, or the Red Sea. I do not have an HF radio or a satellite phone.

Pete

However, the Mayday procedure isn't written entirely for your benefit. There are one or two other people out on the water around thw big wide world and it's one procedure that has to fit all circumstances. And rightly so, it would be madness to have different Mayday procedures in different parts of the world (Even the USA, with its penchant for being deliberately different, has adopted the ITU procedure)
 
The RYA G22 on Page 25 reads:

Mayday, Mayday, Mayday
This is Yacht Calamity, Calamity, Calamity, MMSI 234001234
Mayday Yacht Calamity.
My position is 50 (degrees) 46' (mins) North 001 (degrees) 17' (mins) West
Swamped in rough sea and sinking

Then the RYA gets both the distress message and the distress call wrong. It should be

Mayday, Mayday, Mayday
This is Yacht Calamity, Calamity, Calamity, ABCD1, 234001234
Mayday Yacht Calamity, ABCD1, 234001234
My position is 50 (degrees) 46' (mins) North 001 (degrees) 17' (mins) West
Swamped in rough sea and sinking


The Reeds handbook an page 87 reads:

Mayday, Mayday, Mayday
This is Hot Stuff, Hot Stuff, Hot Stuff
MPTY9, 232001478
Mayday Hot Stuff, 232001478 MPTY9,
My position is .......
(Etc)

which is right.

And once again you make the mistake of assuming that the person dealing with your mayday will have access to the ITU database, or any database for that matter.

Where there is any possibility of confusion, I think that's a reasonable assumption. Unless, of course, you think that there is a significant chance of two vessels whose MMSIs have the same last three digits being in distress simultaneously while in range only of another ship. It could happen, I suppose.

And that there is no possibilty whatsoever of two vessels with the same last three digits operating DSC communications within the receiving range of any station receiving the communications. That is a very large assumption

They'd have to have exactly the same name and call signs too, of course, which must reduce the chances a tad.

The full MMSI number is neither arbitrary nor meaningless (any more than a telephone number is aribtrary or meaningless) and to suggest that it is clearly indicates a lack of knowledge of DSC VHF comms. It;s not just a random sequence of numbers!

I didn't say that the MMSI is meaningless. Read my post again.

I can't really see much to argue about, though. If the ITU want the callsign and MMSI, why not? I doubt, though, that a Mayday call omitting them will get a response of "We're not doing anything till you say it properly." It wouldbe nice if the RYA could teach it properly, though.
 
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Will do just fine for what? It's just three abritrary, ambiguous and ultimately meaningless numbers

It would still leave anyone needing to link the DSC distress call with the subsequent voice communications unable to say with absolute certainty that the two communcations are related to the same incident

Oh it might "do just fine" on a quiet day in the Solent (does such a thing ever happen?) twixt thee and the all singing, all dancing, brand new Coastguard coordination centre with its highly skilled, well trained and experienced operative but can you, hand on heart, guarantee with absolute total and utter certainty that it will "do just fine" in the Maldives, or Corsica, or the Antarctic, or in the Red Sea, or via an HF call from the middle of the South Atlantic or where the initial DSC Mayday is followed up with a satellite phone call or ...

The procedure is as it is because professional mariners and professional radio operators sat down professionally and worked out the clearest and most un-ambiguous procedure that works in any conceivable circumstance. That some leisure sailors cannot deal with a 10 digit number once in a while was not, I suspect, a consideration.

PS. Really the problem is the almost universal, and I include myself in this, failure to take up DSC as a routine part of VHF comms. This I suspect is partly because lesisure sailors, myself included, do not use the VHF all that much and partly because the DSC functions on marine VHF sets are badly implemented and both time consuming and difficult to use. If we were used to using our MMSI number on a regular basis it wouldn't seem at all odd or awkward to need to quote it duing a Mayday

it's people like you wanting "absolute certainty" that came up with this stupid, cumbersome system. Not quoting the MMSI at all would almost certainly be fine, if there was any ambiguity (unlikely) then the CG could ask you for it. The last 3 digits only makes the unlikely 1000 times less likely. That's good enough for me.
 
it's people like you wanting "absolute certainty" that came up with this stupid, cumbersome system.

It takes a certain genius to invent a system - DSC and MMSIs - to make calling easier and then insist on implementing it manually as well, to slow things down even more.
 
Aren't you supposed to have an MMSi programmed into them? Mine has.

Not in my experience. Someone in another thread said that they do program the MMSI into some kind of custom-data field in South Africa. In the UK we don't generally program anything into them - the manufacturer gives each one a unique ID (not an MMSI) and prints that on the label, and we fill in a form to send that to Falmouth. They associate the ID with a bunch of other details (including the MMSI) in a database on shore - those details aren't programmed into the beacon and broadcast.

Pete
 
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Then the RYA gets both the distress message and the distress call wrong. It should be

Mayday, Mayday, Mayday
This is Yacht Calamity, Calamity, Calamity, ABCD1, 234001234
Mayday Yacht Calamity, ABCD1, 234001234
My position is 50 (degrees) 46' (mins) North 001 (degrees) 17' (mins) West
Swamped in rough sea and sinking


(Reeds)

which is right..


Again, thank you. FWIW I've located a rather good tutorial from the Penzance Sailing Club, which seems to cover the syllabus of the SRC course in some depth.

http://www.pzsc.org.uk/radio/index.html
 
Then the RYA gets both the distress message and the distress call wrong. It should be

Mayday, Mayday, Mayday
This is Yacht Calamity, Calamity, Calamity, ABCD1, 234001234
Mayday Yacht Calamity, ABCD1, 234001234
My position is 50 (degrees) 46' (mins) North 001 (degrees) 17' (mins) West
Swamped in rough sea and sinking




which is right.



Where there is any possibility of confusion, I think that's a reasonable assumption. Unless, of course, you think that there is a significant chance of two vessels whose MMSIs have the same last three digits being in distress simultaneously while in range only of another ship. It could happen, I suppose.



They'd have to have exactly the same name and call signs too, of course, which must reduce the chances a tad.



I didn't say that the MMSI is meaningless. Read my post again.

I can't really see much to argue about, though. If the ITU want the callsign and MMSI, why not? I doubt, though, that a Mayday call omitting them will get a response of "We're not doing anything till you say it properly." It wouldbe nice if the RYA could teach it properly, though.

You may be looking at an old book or something. RYA training centres keep up to date on all radio procedures and teach the correct call.
How do I know? 2 reasons really. First is that during 14 odd mob excersises I have conducted so far this week , the correct call has been simulated. Secondly, being married to a VHF assessor who is an ex civil servant, no stone is unturned in the quest for accuracy.....
Should anyone ever ask me for advice, I would say to them 'read it out from the sticker next to your radio and practice often so that when you are fearful and close to death, your rescuers have as much information as possible to save your sorry ass'.

Sail safely!
 
Not in my experience. Someone in another thread said that they do program the MMSI into some kind of custom-data field in South Africa. In the UK we don't generally program anything into them - the manufacturer gives each one a unique ID (not an MMSI) and prints that on the label, and we fill in a form to send that to Falmouth. They associate the ID with a bunch of other details (including the MMSI) in a database on shore - those details aren't programmed into the beacon and broadcast.

Pete

All MMSI numbers have a country code this being the first 3 numbers. These first 3 numbers of the MMSI number is also included in the Unique ID as you call ir (Hex number)
o the
A you said in the other thread EPIRB's supplied for sale in the UK will have the UK country code programmed into the EPIRB by the manufacture and when for sale in Australia will have the Australia country. Any EPIRB's sold in South Africa will have 601 programmed but as I purchased one of my EPIRB's in the UK thus having the UK country code it had to be reprogrammed to reflect the 601 needed to register my EPIRB in South Africa. If any one has an EPIRB registered in another to their ship registration should have their EPIRB reprogrammed to reflect their country of registration. This may not be enforced in all countries but in South Africa it is and checked every year on the yearly safety inspection.

Have a look at the URL's I posted.

I also have a card with the MAYDAY procedure printed on my nav desk but it is the old procedure so I will update as needed. I also have a card with my yachts name in the radio alphabet for easy of sending a MAYDAY. I will add my callsign and MMSI number so I don't have to remember then in the heat of the moment if needed.

One possible problem with numbers over a radio call is as far as I know there are no radio "alphabet" for numbers so could easy be miss heard where ship name can be spelled out.
 
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PS. Really the problem is the almost universal, and I include myself in this, failure to take up DSC as a routine part of VHF comms. This I suspect is partly because lesisure sailors, myself included, do not use the VHF all that much and partly because the DSC functions on marine VHF sets are badly implemented and both time consuming and difficult to use. If we were used to using our MMSI number on a regular basis it wouldn't seem at all odd or awkward to need to quote it duing a Mayday
I agree.
And it is not just us the amateurs. Professional users do not seem to be muxh more familiar with the system.
Two years ago I heard Dover Coastguard calling a ship in the Straits. After a few calls without any response, using the ship's name and callsign, the coastguard called the ship citing its MMSI number. Needless to say there was no response either.
Why the coastguard should try calling a ship by its MMSI number still mystifies me. I always thought that the MMSI was meant to be used as the equivalent of telephone number and that using it that way triggered an alarm on the ship's bridge that is hard to ignore
 
One possible problem with numbers over a radio call is as far as I know there are no radio "alphabet" for numbers so could easy be miss heard where ship name can be spelled out.

The pro-words for numerals are included in the International Code of Signals. Unaone, bessotwo, terratree,kartafour etc.,

You can get a free copy from the US govt or pay for one from the UK.
 
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