MMSI Numbers

Have used the DSC routine call several times towards ships, when I had doubts about their intentions, I haven t counted but say 20-30times, I usually input ch72 instead of the usual 06 which is more likely to be busy, they *always* replied. Very personal statistics of course, but surely I will continue using this system when need be.
Also, I think the call is automatically logged on the voyage recorder, should they not reply to DSC, I suspect a voice call on 16 with their name/MMSI and the wording "collision course" would probably awaken anyone except some very low standard crew ships; though I have never had the need to do so.
A long time ago - well, ten years ago - I was under full sail heading south closely parallel to the Croatian Istrian coast watching a fast hydrofoil ferry heading straight for me. Heading straight is incorrect, it had a wavering course shown by the track on the netbook screen running a beta version of OziExplorer with AIS overlay, but its average was close to a reciprocal of mine and with a closing speed of over 48 knots - my contribution to that was a mere 5 knots. At 1 nm distant and a potential collision less than 2 minutes away I transmitted a "what are your intentions?" call on channel 16 using the ship's name from the AIS target list. The early AIS receiver had no connection to my DSC radio and it never would have been feasible under those circumstances to punch in a 9-digit MMSI number.

No sooner had I released the TX button when the helmsperson swerved to starboard in a sudden manoeuvre that must have spilled all the drinks in the bar, but no radio response. It was clear to me that channel 16 was being monitored by the instant reaction and, as a bonus, it certainly was by the local shore station that later called me for a status update. I have since wondered if the same shore station watch was made on the DSC frequency with no emergency activation. Certainly in the Adriatic channel 16 is still a well-used calling frequency before changing to a working one.
 
Certainly in the Adriatic channel 16 is still a well-used calling frequency before changing to a working one.

And, as a bonus, it provides some great entertainment.

This summer we had a boat calling Split Control with a Mayday saying that they were taking on water. The radio operator asked whether the boat was sinking and the response was that there was water sloshing around, however, it didn't appear to be getting any deeper. At that point another mayday interrupted proceedings and when the first maydayer asked what was happening to her call the response from the operator was that a proper mayday had now been called in and would she please get off the air. ;)

Richard
 
You may be a clever chap, but you were still rude to our Antipodean cuz! :)
I come from a long line of cynical Clydeside engineers, we have a reputation of being rather direct.

School friends who live in Australia (NSW and Queensland) inform me that a) Australians are very direct and b) prefer people to be rather direct to them. This is a nation that calls us British "poms" and invented "sledging" while playing cricket and not wooshing down the Snowy Mountains in New South Wales on sledges.

Perhaps one reason Sir William and Lady Connolly the New Zealand-born Australian psychologist have been married so long.
 
I attributed Sandy's query as being solely my fault with an inadequately scripted opening post and query, though the initial comment did throw me (its an International agreement that users of VHF and HF must have some form of licensing (which usually involves some form of training). So the idea that somehow Australia was not a party to the agreement did surprise me (given that we regularly pick up errant yachtsmen from the Southern Ocean as part of a similar agreement).

We immigrants develop thick skins quickly, after all we are just foreigners and jonny come lately - I think its the perpetual sunshine and the fact 90% of us live within 100km of the sea that gives us the thick skins :)

The thread does illustrate that what we (you) think is normal and established common practice does not mean its common practice everywhere else.

We are required to carry EPIRBs when offshore. The implication is that authority accept we will use them in an emergency - and again by implication are geared up to both receive the signal and act (which they do). This appears to negate any need for DSC as an emergency facility (though redundancy is no bad thing) This might in part explain our lack of use of DSC. What is the attitude to EPIRBs in Europe?

If the chips were down - we would set off the EPIRB (that' why we carry it), send a voice Mayday by VHF and HF and finally send an auto DSC alert - and respond to whatever replied - the priority would be the EPIRB and attending to whatever the emergency might be (I'm assuming fire, sinking, MOB - not running out of fuel, nor forgetting to switch off the iron).

Jonathan
 
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its an International agreement that users of VHF and HF must have some form of licensing (which usually involves some form of training).

I've heard, though, that the US doesn't require any operator's certificate or training for radio operators on its leisure vessels. Realistically this probably doesn't make a whole lot of difference for VHF (it's easy to use, and mandatory training here doesn't stop the occasional numpty anyway) but it's a bit surprising for HF.

Pete
 
I think people also need to know if you are incapacitated on your boat , cant speak ,etc, pressing the DSC distress button with MMSI number gives the authorities your boat , name , class, normally how many on board GPS location, yes rare that a person can not talk but if knocked unconscious and very groggy going in and out of unconscious , pressing a button and knowing that all that information is sent to the rescue services is a great piece of mind. (sorry pun)
My PLB will do that.

As this thread has drifted from MMSI to DSC, I have chosen not to fit a DSC VHF and if I did, I would not program it with MMSI # as sailing solo I can do without getting all the DSC alarms!
 
From his various comments, I think DSC and not MMSIs is what the OP meant in the first place :p

Pete

Now you've got me thinking Pete.

I interpreted "Do many people use MMSI numbers? And if so, what for? Here it costs us nothing to have an MMSI number - but in terms of a leisure vessel it seems a bit pointless - or do people use the numbers a lot for DSC communication" to mean that Jonathan was actually interested in MMSI numbers and their uses and hence my response days ago.

However, now I'm wondering whether you are right .... in which case my answer was a total non-sequiter. :o

Richard
 
My PLB will do that.

As this thread has drifted from MMSI to DSC, I have chosen not to fit a DSC VHF and if I did, I would not program it with MMSI # as sailing solo I can do without getting all the DSC alarms!

Not if your not in the water , most PLBS fit within the life jacket and operate if you go for a swim , most head injuries will occur by swinging booms and being tossed about your cabin with flying debris,
Also with MMSI if you have AIS you can identify a ship coming towards you in open water , say in the Atlantic and at night and you tossing about , and you can contact the ship directly using MMSI rather than voice calling, it might make the officer on watch actually take notice .
Why would people not consider a very useful aid on contacting other boats and easily identifying them with AIS, also in a distress situation one press of a button will go the coastguard who can easily identify the boat , gps location , potential number of people onboard , this will aid them
A. getting to you quickly
B. prioritizing what they need to send
C. VHF distress can also be picked up by other boats and ships in large oceans if they are in Range.

I have never been in a situation were I needed to call for help, but in previous jobs I have been in High risk areas , seen my fair share of blood , and mayhem , and I have seen people crumble in a stressful situation , getting all that information to the coastguard via talking in a very stressful situation could cost lives, press the button !!
 
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MMSI Numbers i assigned by national authorities, must be changed if flag state changes.
First three digits is country specific.
DSC alerts will not be sent by VHF if missing,
Also used in AIS transponders, EPRIB.
The MMSI number for other ships shows up in my pluotter
I can send a position request DSC message to my handheld VHF and get dingy position back.
you can search here https://www.itu.int/mmsapp/ShipStation/list
This is my vessel data https://www.itu.int/mmsapp/shipstat...6g9AaTwEiF5g9JSlynUgAxDni54MueTYry8uLTworGzIj
 
...
I can send a position request DSC message to my handheld VHF and get dingy position back.

...

That is a very useful feature of AIS. My wife goes wind surfing and paddle boarding along the coast and takes the DSC handie with her - it is reassuring to be able to check on her position via the plotter. If she gets into trouble, I can go to rescue her.
 
From his various comments, I think DSC and not MMSIs is what the OP meant in the first place :p

Pete

Yes and no - it started with the idea we had these MMSI numbers - did anyone actually use them. Not having AIS I'd forgotten the necessity of the number, this led to DSC radio - where widespread use of MMSI numbers 'started' for the leisure market (AIS coming later) - so it, the thread, sort of grew like Topsy. And I now wonder of the value of DSC as an emergency alert when we are mandated to carry EPIRB (and surely AMSA, who receive the EPIRB alert, are better at coordinating resources than volunteers in a coastal radio station who receive the DSC alert?

Maybe I should have thought more about the wording of the original thread and then had 3 or 4 other threads.

:)

Jonathan

To elaborate on the original post

I did wonder, those Sunday musings - I know that yacht on the horizon, I know its name and the owner. How do I find their MMSI number - that's where I started. I then wondered do people actual key in MMSI numbers and make DSC calls.

I gather that the numbers are published as a directory (which I suspect leisure sailors do not carry - internet search - in Oz you can make a search by vessel, not by owner - not sure on latter)

As I say we, in Oz, don't as far as I am aware use, or commonly use, DSC - so I wondered what happened elsewhere - and then the thread developed.

Do I understand there is no mandatory carrying, as we do here, of EPIRBs?

J
 
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Do I recall correctly that the digital DSC alert (e.g. Mayday) is also more likely to get through uncorrupted than voice in marginal range/conditions? (Or is it like digital radio where if it's marginal, you get nowt?)

If shorthanded, there is also the advantage of sending an efficient distress signal in a very short time: if the correct procedure dictates a dsc alert followed by a complete voice communication, in case of an MOB situation with two persons onboard, one can press the red button (which may also store the position as a waypoint, instead of the gps mob button), grab the microphone and say "mayday confirmed, please come to help I cannot reply I try to recover my husband" and concentrate on other tasks instead of spending minutes and minutes with various "say again longitude not understood", etc etc
 
.....

Do I understand there is no mandatory carrying, as we do here, of EPIRBs?

J

EPIRBs are mandatory round here on certain classes of vessel including, I believe, coded charter boats. My experience is that few leisure sailors go to the trouble of voluntarily carrying one - PLBs seem to be more popular. My wife and I both carry a PLB attached to our life jackets - reassuring to know that you could quickly summon help if you fall overboard and not expensive to own. The other advantage of a PLB is that it is not restricted to maritime use - when our son took it into his head to travel far from civilisation in the Canadian back-of-beyond, we lent him a PLB to carry with him. We hear every year of someone getting lost in the Oz Outback and either dying or coming close to it - why do you guys not carry PLBs whenever you go far from civilisation?
 
I suspect the losses in our outback are similar statistically to your losses in the Cairngorms or Snowdonia. But I, and the rescue authorities, cannot understand why people do not carry PLBs in either our outback or your Cairngorms. They can be rented its another one of those no brainers.

Our EPIRBS are mandated on any vessel going offshore - in our case locally - into the Tasman Sea. Coding has nothing to do with it.

Jonathan
 
Do I recall correctly that the digital DSC alert (e.g. Mayday) is also more likely to get through uncorrupted than voice in marginal range/conditions? (Or is it like digital radio where if it's marginal, you get nowt?)

Our authorities say that with the digital signal you get longer range. I am not convinced as like digital radio/TV bad weather where analogue can be corrupted but some will get through and can be repeated on request. With digital the error checking will determine what and if a whole signal gets through. The retry patrol will also dictate what and how many retrus will take place.

I see EPIRB's and DSC radio as 2 complementary methods of getting help.

DSC can get help quicker is some one is in range but EPIRB's will get help any where but will take time for conformation of an emergency.

The other thing about EPIRB's is that there is no conformation that the signal has been received so you don't know is some one is coming. DSC does have the ability to talk to the receiver to see how long they will take to get to you.

Foe my class of vessel EPIRB's are mandatory and the authorities are trying to make DSC mandatory by they are not and plan to stop Ch16 monitoring but its still a calling channel for most/all commercial vessels arriving in South African anyway.

If I am on night watch alone I always attach my DSC hand held to me so I can call my yacht or other vessels if I go over board.

One of the nice things about combined DSC and AIS receive radions is that you can make a call directly to a close vessel just by picking the vessel from a list that on my radio lists then in CPA order closest first.
 
EPIRBs are mandatory round here on certain classes of vessel including, I believe, coded charter boats. My experience is that few leisure sailors go to the trouble of voluntarily carrying one - PLBs seem to be more popular. My wife and I both carry a PLB attached to our life jackets - reassuring to know that you could quickly summon help if you fall overboard and not expensive to own. The other advantage of a PLB is that it is not restricted to maritime use - when our son took it into his head to travel far from civilisation in the Canadian back-of-beyond, we lent him a PLB to carry with him. We hear every year of someone getting lost in the Oz Outback and either dying or coming close to it - why do you guys not carry PLBs whenever you go far from civilisation?

In the UK as stated their is no law to say you must(leisure only) have an EPIRB or DSC ,and you do not need life jackets or any licence to say that you are competent, in fact I think the UK has the most relaxed laws for the leisure boat in the Western World.
Some might say this is a good thing as for once the state does not interfere , but then you can argue and many threads on this have, that certain safety procedures should be mandatory , as there are many that go out with nothing.
As I sail with my family the risk factor and fear factor kick in and I have everything ;)
 
Not if your not in the water , most PLBS fit within the life jacket and operate if you go for a swim , most head injuries will occur by swinging booms and being tossed about your cabin with flying debris,
Mine isn't, it is to hand from cockpit or saloon.

Also with MMSI if you have AIS you can identify a ship coming towards you in open water , say in the Atlantic and at night and you tossing about , and you can contact the ship directly using MMSI rather than voice calling, it might make the officer on watch actually take notice .
Why would people not consider a very useful aid on contacting other boats and easily identifying them with AIS,
Yes, I identify them with AIS - on my Chart Plotter. I find it easier to call them by name than spend time putting in / searching for MMSI's on the radio. Calling them by name has always had the desired result.

also in a distress situation one press of a button will go the coastguard who can easily identify the boat , gps location , potential number of people onboard , this will aid them
A. getting to you quickly
B. prioritizing what they need to send
C. VHF distress can also be picked up by other boats and ships in large oceans if they are in Range.
I'm not sure about 'potential number of people onboard', but my PLB will alert the powers that be in a 'distress situation one press of a button' and I can follow it up with a VHF voice call as, if memory serves correctly, you also should after a DSC alert.

I have never been in a situation were I needed to call for help, but in previous jobs I have been in High risk areas , seen my fair share of blood , and mayhem , and I have seen people crumble in a stressful situation , getting all that information to the coastguard via talking in a very stressful situation could cost lives, press the button !!
If you are that sort of person, then you should have a button to press!!!
 
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