USCG broadcasts of Mayday and MMSI

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rgano

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Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
Day before yesterday, the USCG broadcast on channel 16 VHF that they had a Mayday sent out from an MMSI with no GPS tag. They broadcast the MMSI number and an estimated position between Orange Beach, AL and Pensacola, FL. This broadcast was repeated over and over about every twenty minutes.

As to why no GPS tag was attached, there are tons of possibilities, chief amongst them that the owner did not bother to make the connection or did not know how. Sure, the GPS could have been down for fire or flooding or simply turned off and some kid hit the VHF's red button. Hard to say.

Here's my question; why did the USCG not broadcast a boat name or at least the information registered with the MMSI?

Could they not have just called the phone numbers associated with the MMSI or even sent the cops to the address to check?

Their handling of it on channel 16 just seems a bit off.
 
You can have an MMSI number, and not provide all of those details. It is possible that the owner of the boat not only failed to connect the GPS, but also failed to provide the sort of information that you are thinking the USCG should have been using.
 
Some boats do not have a name or they didn’t register the name.
 
MMSI through BoatUS requires registration or documentation number which is then logged into national database. Address and phone information could be years old, missing, or simply bogus. I doubt USCG has access to state databases.

MMSI is pretty useless without GPS connection and each manufacturer has a different wiring color code scheme so understandable why so many people get it wrong.

An accidental push of the red button is unlikely. You then have to select the right menu item before a distress call will go out.
 
It's been a long time since I registered an MMSI, but I thought there were certain fields required which would be enough to get the ball rolling on identifying the person who registered, even if not the current owner. Assuming USCG has access to that, fifteen minutes on the phone could yield quite a bit of info, maybe enough to give other boaters a hint as to what sort of vessel to look for.
 
Greetings,
Mr. r. No idea about your question but a comment on a CCG (Candian Coast Guard) broadcast I hear a number of years ago.
While transiting along the St. Lawrence River, we heard a "help look for missing windsurfer" message. Evidently the "sailor" was somewhere off XX Point. No lat/long, just XX Point.


Problem with us was we weren't local and XX Point was nowhere to be found on any of our charts. We did several binocular sweeps to no avail.
 
The good thing about a local geographic reference is that those close by to the distress probably also know the local position and can respond quickly. LAT/LONG rattled off and not copied down to me is useless until I know I am in the area. At that point hopefully I am talking directly with a local coordination center or rescue units if I think I am local to the distress.

The rescue coordination center should think in terms of rapid local response, but eventually broadcast enough info that other than locals can assist if they recognize the distress position.
 
MMSI through BoatUS requires registration or documentation number which is then logged into national database. Address and phone information could be years old, missing, or simply bogus. I doubt USCG has access to state databases.

MMSI is pretty useless without GPS connection and each manufacturer has a different wiring color code scheme so understandable why so many people get it wrong.

An accidental push of the red button is unlikely. You then have to select the right menu item before a distress call will go out.

I don't believe all radios require more button pushing than just the distress button for a basic mayday.

https://wow.uscgaux.info/content.php?unit=170&category=dsc-vhf-radio-rescue-21

On the front of the radio you’ll see a red Distress button. Just press that button. This is where DSC and Rescue 21 take over. Once you press the distress button, your radio sends a digital signal over Channel 70. That signal goes to the Coast Guard, but it also goes out to all boats within range that have DSC/VHF radios. The radio will continue to send the message until someone acknowledges it. This message is fast (only 1/3 of a second), accurate, complete and automatic. It will continue to broadcast even if the skipper is incapacitated.
 
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SO add to no GPS tag.....a subsequent owner that never reregistered the MMSI. So all of that information is useless. Am I missing something in saying that? I know a few boats around here that show up on AIS the old name of the boat so I assume it is the old information associated with that number.
 
Yes, lots of people are too lazy or lack the technical skills to update the electronics when they buy a boat. Too bad because it is a great safety feature. One button push for a distress call with location if it is hooked up.

One issue I have seen is the local CG stations speak so quickly that many people can’t understand what they ase saying. I spent 30 years working closely with the CG and tried telling them to slow down and enunciate on the radio. Unfortunately they seem to train to get it out as fast as possible. But if no one can understand it it is pretty useless. And as you get older your hearing isn’t as good and lots of boaters are getting up there in age.
 
Long/lat locations have little immediate meaning to me. In coastal waters, reference to physical (real) locations would be most helpful.
 
On the front of the radio you’ll see a red Distress button. Just press that button.

And hold for three seconds. Otherwise you will be presented a menu of options to select. Many people would just press the button and assume the distress message went out. Not so.
 
With current technology is there any relay system of the distressed vessel location.
A lot discussed about an MMSI going out, not registered etc. Who cares if that signal went out with a gps it should be enough to be received by others.
Too bad our chartplotters with gps cannot receive a bip on the screen indicating a distressed vessel.
As others have said I have yet to be able to write down a lat/long let alone find a pen and paper before the CG is done talking.
Give me a local landmark.
 
My plotters show DSC distress contacts if they went out with GPS data included.

OpenCPN does this, too, showing them as a type of pseudo AIS contact.

I figured most plotters did this.
 
Long/lat locations have little immediate meaning to me. In coastal waters, reference to physical (real) locations would be most helpful.

I actually lobbied(over the radio) our local station and it helped. Every time a PAN PAN went out, I would wait a proper amount of time and call them and switch to 21a and explain that lat/long means nothing to everybody and that they are wasting their tie and potentially endangering the lives of people. After a few times, the USCG Galveston will say lat/long and then give approximate location in reference to landmarks.
 
Also as it relates to Emergency DSC and AIS, I just installed the new Cortex. It would be difficult to make a mistake of the call NOT going out. That is a slick little unit. Not perfect. But has a lot of stuff integrated into one handset.
 
There seems to be several different systems to do several different things.
For a mayday we have VHF 16 to CG who relays. AIS and DSC, chartplotters etc are not involved. For those of us that would respond we need to have VHF on 16 and listen.
NOT, too much chatter.

Back when I was on call 24/7 I did not need anything as they had my phone/pager number. Now, VHF is on 16 while moving, eyes always looking.
At anchor I could be around the corner and not know you need help.

Too bad there is not a dedicated quiet channel on which the coast guard can wake us up, assuming we want to be on call to assist
 
There seems to be several different systems to do several different things.
For a mayday we have VHF 16 to CG who relays. AIS and DSC, chartplotters etc are not involved. For those of us that would respond we need to have VHF on 16 and listen.
NOT, too much chatter.

Back when I was on call 24/7 I did not need anything as they had my phone/pager number. Now, VHF is on 16 while moving, eyes always looking.
At anchor I could be around the corner and not know you need help.

Too bad there is not a dedicated quiet channel on which the coast guard can wake us up, assuming we want to be on call to assist

Amen! Which is a pet peeve of mine. On the Chesapeake there is so much loud 25 watt chatter of calls to marinas, fuel docks, radio checks, and resteruants that I often turn off 16 to stay sane and only monitor 13. Making it worse, if they dont get a response in three seconds they keep repeating the hail till they do. The CG should put these non essential hailing calls on another channel.
 
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Sold my boat. Of course kept my license but the station licenses for all the various devices except those attached to our PFDs went with the boat.
As part of the sale reserved my boat name. New owners are experienced bluewater sailors. Did their applications to transfer station licenses at time of purchase. For months I’d see my boat name attached to my prior boat on MarineTraffic. New owners chased that and told me that due to Covid and other issues the feds remain so upside down that they’re terribly backlogged. Last week MarineTraffic finally switched to the new name. More than 6 months had passed.
Most of my screens since forever have lat/long always displayed. Even coastal we log. Two columns have always been lat/long. We also keep a radio log. It’s how I was trained so is part of the routine. Maybe lat/long lurk in a small overlay box but lat/long is there on the screen. Took me a little while for my brain to accept it as digitalized. But now can look at it and fairly accurately immediately translate those numbers into distance and direction from me when given a new string. I’m not in an airplane so only need to attend to the last few numbers in the string. Most people can hang on to a telephone number long enough to dial those 10 numbers. Most can hang on to the last 4 of lat then long. Still, agree also giving nearby landmarks would be helpful.
Remain amazed how little dsc is used and how many boats still don’t have AIS transceivers. Open mikes drive me nuts. But that’s another discussion.
 
In my area, USCG (and CCG) typically give an "in the vicinity of XX" as a geographic reference before they give the lat/long. It allows making a quick decision of "do I need to listen closely and get the exact location or is that 50 miles away from me?"
 
My plotters show DSC distress contacts if they went out with GPS data included.

I figured most plotters did this.


Not as straightforward as it might seem. DSC distress calls received on VHF only get transferred to most plotters if a NMEA0183 connection, directionally correct, exists between radio and MFD.

And then the radio must be programmed to transmit those sentences... and the plotter must be programmed to accept and display the data. Usually just menu options, I think, but if the user doesn't know they're necessary...

(Most?) Radios connected only be NMEA2000 apparently can't usually transfer the distress call positional data and/or (most?) plotters can't handle the input that way anyway.

-Chris
 
Hey Chris,,

I'm not sure that I understand the concern.

Like any other NMEA 0183 device a VHF-DSC radio can only send data to a chart plotter if it is connected to the chart plotter. And, like any other device this means that the wiring between them needs to be done correctly.

But it is basically just the A and B wires that some think of as send and receive, plus power and shield.

These wirwa need not be directly connected between devices.. Like any other NMEA 0183 device, it can be connected via via multiplexer, bridge, repeater, etc. And, like most NMEA 0183 talker devices, most DSC radio outputs can simply be split to go to two chart plotters or other listeners (this is usually "off label" and may not be the best idea).

As far as NMEA 2000 is concerned, it explicitly supports DCS alerts via PGN 129808.

Also, DSC alert messages are among those that are broadly understood and nearly universally, if not universally, translated in both directions by bridges between NMEA 0183 and NMEA 2000, including derivatives like Seatalk NG.

My own system has a NMEA 2000 (Seatalk NG) backbone into which all of my NMEA 0183 data goes (and comes from) via a NMEA 0183 multiplexer. This includes my VHF-DSC radios. The multiplexer filters the traffic per device to avoid overloading any of them. The OpenCPN plotters get the data via a NMEA 2000 to USB dongle that translates 0183<->2000.

I guess what I'm saying is that hooking up my radio was just running wires to the NMEA-0183 multiplexer and telling the multiplexer not to send anything there, except GPS data (as a backup to the internal GPS).
 
Yeah, didn't mean it was a huge problem, just that not everyone may have connected the necessary wires. And/or check the various menu options. There's a thread going on cruisersforum.com just now about DSC and plotters... OP is trying to use only NMEA2000... without useful results, as far as I can tell.

Useful to know that PGN; I might echo that to him in case he hasn't found it yet.

I stumbled across the issue on our own installation after an actual distress event. No plot on the MFD, but MFD manual described the capability. Turned out I needed the 0183 wires -- out from VHF and IN on MFD -- connected, and for some reason our installer didn't do that.

Could have been an easy enough solution, but then... we updated our radios, connected only via NMEA2000... and then learned the radios wouldn't transmit position data via NMEA2000. As I remember it, the MFD only accepted that data via 0183. And I had to have it turned on (check mark on menu).

I'm a bit hazy on details now, but the bottom line was that I never got around to connecting the extra 0183 wires, so never could get distress plots on the MFD.

-Chris
 
My plotters show DSC distress contacts if they went out with GPS data included.

OpenCPN does this, too, showing them as a type of pseudo AIS contact.

I figured most plotters did this.

Not as straightforward as it might seem. DSC distress calls received on VHF only get transferred to most plotters if a NMEA0183 connection, directionally correct, exists between radio and MFD.

And then the radio must be programmed to transmit those sentences... and the plotter must be programmed to accept and display the data. Usually just menu options, I think, but if the user doesn't know they're necessary...

(Most?) Radios connected only be NMEA2000 apparently can't usually transfer the distress call positional data and/or (most?) plotters can't handle the input that way anyway.

-Chris

Yeah, didn't mean it was a huge problem, just that not everyone may have connected the necessary wires. And/or check the various menu options. There's a thread going on cruisersforum.com just now about DSC and plotters... OP is trying to use only NMEA2000... without useful results, as far as I can tell.

Useful to know that PGN; I might echo that to him in case he hasn't found it yet.

I stumbled across the issue on our own installation after an actual distress event. No plot on the MFD, but MFD manual described the capability. Turned out I needed the 0183 wires -- out from VHF and IN on MFD -- connected, and for some reason our installer didn't do that.

Could have been an easy enough solution, but then... we updated our radios, connected only via NMEA2000... and then learned the radios wouldn't transmit position data via NMEA2000. As I remember it, the MFD only accepted that data via 0183. And I had to have it turned on (check mark on menu).

I'm a bit hazy on details now, but the bottom line was that I never got around to connecting the extra 0183 wires, so never could get distress plots on the MFD.

-Chris


Great thread!! I have both my VHF radios connected to my MFDs. Both VHF radios have Lat/Log on their screen.

It would be nice if you do hear a Mayday, then the position on my MFD would be awesome instead of writing down the position and manually inputting it to the MFD.

Now time to breakout the manual on my Raymarine.:thumb:
 
Hey Chris,

Yeah. You aren't alone. I think most people get DeviceX, hook it to power and antenna/transducer, and call it a day. It does whatever it was primarily intended to do.

As far as 2ndary features available when integrated? I think a lot of people just take a pass. I see a lot of boats where a new owner tests a feature and it turns out it never worked, despite multiple owners since install. Sometimes it was disconnected by an intermediate owner and just never reconnected.

I used to think it odd. Now I just figure it is among the many personal choices we all make.
 
Nowadays, when out on the water it is recreational. VHF on 16 or scan mode, chartplotter on.
I have seen more whales than most because I am always searching, by doing that, I am also aware of the boats on the horizon. I have gone along side any that has stopped and ask if they are OK, but otherwise CG will have to send an alert.

I would like a chartplotter that has AIS built in and CG could transmit lat/long onto it.
 
I would like a chartplotter that has AIS built in and CG could transmit lat/long onto it.


Well, what we've been describing is that some (maybe most) VHF/DSC radios which receive position data (lat/long) from a distress call can in fact relay that to a plotter. And then the plotter can display it. (Ours would only have worked with distress positions, if we had had it fully wired, not run-of-the-mill DSC position reports.)

Anyway, no CG involvement required. If you have everything hooked up and set up correctly.

AIS not required for that. Not aware of MFDs with built-in AIS (latter usually best with it's own GPS and VHF antennas). Our AIS was a block box (with its own antennas), hooked to our MFD. Nifty, but not related to VHF/DSC distress calls.

Do you have a DSC-capable VHF? A plotter? Are they connected? You maybe already have the capability...

-Chris
 
Well, what we've been describing is that some (maybe most) VHF/DSC radios which receive position data (lat/long) from a distress call can in fact relay that to a plotter. And then the plotter can display it. (Ours would only have worked with distress positions, if we had had it fully wired, not run-of-the-mill DSC position reports.)

Anyway, no CG involvement required. If you have everything hooked up and set up correctly.

AIS not required for that. Not aware of MFDs with built-in AIS (latter usually best with it's own GPS and VHF antennas). Our AIS was a block box (with its own antennas), hooked to our MFD. Nifty, but not related to VHF/DSC distress calls.

Do you have a DSC-capable VHF? A plotter? Are they connected? You maybe already have the capability...

-Chris
To be clearer, I do not want two devices, not interested. And you can have your system but it will not show you a boat unless it has AIS, which most pleasure boats may not have.

BUT if the CG could send a signal to a chart plotter spoofing AIS then you can see the distressed vessel location. Simple one device.
 
Most AIS receivers also have a DSC receiver in them, so they should be able to receive the location of a DSC distress call and provide it to the plotter. Assuming there's location data present in the signal, of course.
 
To be clearer, I do not want two devices, not interested. And you can have your system but it will not show you a boat unless it has AIS, which most pleasure boats may not have.

BUT if the CG could send a signal to a chart plotter spoofing AIS then you can see the distressed vessel location. Simple one device.

Fair enough. Don't think that exists, though.


Most AIS receivers also have a DSC receiver in them, so they should be able to receive the location of a DSC distress call and provide it to the plotter. Assuming there's location data present in the signal, of course.

Didn't know of any AIS receivers with DSC receivers built in. I've read about units that work the other way around, a DSC-capable VHF radio with add-on AIS receiver either built in or as an option. The ICOM 605s we eventually moved to could have had an AIS option (receive only) but since we had a black box AIS already I didn't need to fool with that.

-Chris
 

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