EPIRB versus AIS PLB

[ShinyShoe]

P.S. if the Iridium monthly subscription were lower, the Garmin locator would seem to be the ideal solution...

Would it? Does it send realtime position data to mothership every minute

 

[maby]

Would it? Does it send realtime position data to mothership every minute

It certainly has an SOS mode - but I can't comment on its transmission pattern. In its favour, it is a bi-directional device - you can both send and receive messages, so you will be able to interact with your rescuers. The only real downside is a monthly subscription of more than £10.

 

[requiem]

Unfortunately - even on this thread there is no general understanding of what constitutes a PLB. There are numerous posts at the beginning stating a PLB MUST transmit on 406 and / or it must be a SARSAT device. Neither of the statements are true.

Indeed, PLB as a generic term could be taken to mean many devices; the only way around that would be to ban the use of the term for anything but a 406 MHz beacon. As far as I'm aware, only the US has explicitly gone that far (47 CFR subpart K).

The mentioned "sMRT V100X Man" is a good example of the confusion that can happen when the terms are used carelessly. I'm not surprised at the occasional confusion on forums, or that a company from certain regions might be careless with labeling (I've seen it on radios and on climbing equipment), or even that the RYA might decide to muddy the waters by inventing their own term (it's not the first time).

Specific restrictions on labeling aside, the usage of the term PLB is remarkably consistent across governments and industry. When the Danish Maritime Authority refers to a PLB, it's in reference to a 406 MHz device. When EASA allows use of a PLB on aircraft as an ELT alternative, it's a 406 MHz device. Canada's RSS-287 considers PLBs to be 406 MHz units, prohibits the sale/import/manufacturing of PLBs that only operate on 121.5/243 MHz, and explicitly notes that other MSLDs are not considered PLBs.

 

[requiem]

Would it? Does it send realtime position data to mothership every minute

If you're willing to pay, it will send automatic tracking points every two minutes. Seems a bit overkill to me. I find hourly is more reasonable on land, and even longer would be fine at sea.

 

[Uricanejack]

A PLB doesn't mean "I fell in the water" it means "*I* am in distress". An EPIRB means "My boat is in distress". Activating either would be fine for a yacht 100 miles offshore, dismasted, with gear tangled in the prop. But the boat hasn't sunk and no-one is in the water.

An EPIRB has some specific extra requirements. It auto activates when wet (hence you associate it with sinking). It transmits at least 48 rather than 24 hrs (that's a battery size thing... PLB needs to be compact to be personal). It floats and should transmit by itself floating (no need to orientate the antenna).

My personal view is on a yacht, where life jacket worn all the time, a PLB on the lifejacket offers almost all the advantage of the EPIRB provided the wearer is able to manually activate it (and if they aren't then no rescue will ever be quick enough to matter).


PLB or EPIRB will get identical SAR response AFAIK.


Agreed. But 100miles offshore, your best chance of rescue (and survival) is your mothership. So giving them a "homing signal" is what is needed..

The delay in satellite is probably 30mins+, then the phone shore contacts, launch assets. Typically it will be an hour after you activate it before assets are mobile to you. If that is a help, 100miles out. Depending where you are. They might rescue you an hour later. Maybe 2. Unless you are dressed for immersion your survival will not be great. Sail single handed - it's your only hope (and there have been successful rescues). Sail a well crewed boat using AIS... You could be sipping hot cocoa before the satellite system has even kicked in.

The ultimate device:

AIS - water activated
DSC - water activated (possibly with some form of delay/manual activation before being a full DSC alert)
Satellite - perhaps not water activated (let's avoid mid Atlantic asset deployment due to false alarms where boats can't be contacted)
Odeo type hand flare for positioning
Waterproof
Floating
Floats upright
Teathered to LJ.
USB port to plugin and read diagnostics on own PC
? Rechargeable if not replaceable battery

Good information. Like I said I am no expert on gadgets.
I think we agree there is a distinct difference between an EPIRB and a PLB. Later posts indicate the definition of a PLB may be a bit vague.
The most important differences appear to be the auto activate when in the water. And the vessel or just the person in distress.
Though batter life of an EPIRB might be the difference.

My thoughts still EPIRB for the boat. I don’t think a PLB replacing the EPIRB is a wise choice. It has its own purpose which is an additional option. I don’t have either.
Cost I suppose is a factor when kitting out your boat. I haven’t priced them. If you have PLB I guess you need one for everyone which kind of puts the price up.

 

[Uricanejack]

Indeed, PLB as a generic term could be taken to mean many devices; the only way around that would be to ban the use of the term for anything but a 406 MHz beacon. As far as I'm aware, only the US has explicitly gone that far (47 CFR subpart K).

The mentioned "sMRT V100X Man" is a good example of the confusion that can happen when the terms are used carelessly. I'm not surprised at the occasional confusion on forums, or that a company from certain regions might be careless with labeling (I've seen it on radios and on climbing equipment), or even that the RYA might decide to muddy the waters by inventing their own term (it's not the first time).

Specific restrictions on labeling aside, the usage of the term PLB is remarkably consistent across governments and industry. When the Danish Maritime Authority refers to a PLB, it's in reference to a 406 MHz device. When EASA allows use of a PLB on aircraft as an ELT alternative, it's a 406 MHz device. Canada's RSS-287 considers PLBs to be 406 MHz units, prohibits the sale/import/manufacturing of PLBs that only operate on 121.5/243 MHz, and explicitly notes that other MSLDs are not considered PLBs.

Good information.
Particularly since I live in Canada.

 

[Uricanejack]

I have actually been looking for something without really knowing much about them. Or making the connection its basically the same thing as a PLB.
Not for sailing. I don’t plan on falling of my boat. Who does?
I was looking for a satellite beacon which I guess is a PLB for riding my bike. I often ride some pretty lonely roads. Even People in pick up trucks disappear every year.
I don’t plan on crashing my bike either but the odds suggest it’s a lot more likely.
Choices appear to vary between subscription or no subscription. They all have to be manually operated. I was hoping there might be a kind which activate after an impact. doesn't appear to be an option.
So for a PLB to work, you have to be consious, capable of movment, fingers working, and be able to reach it.

 

[miha90]

As a side note, the PLB will most likely be fine for shore cruising where help is only a couple of hours away. For anything else the EPIRB in a necessity as it has a much larger battery thus longer operating time.

 

[bedouin]

I'm rather skeptical about AIS beacons based on my experience of range for hand held VHF transceivers. My wife and I carry 406 PLBs - we may invest in AIS beacons this year.

That is what concerns me too. If are MOB and can't see the boat then AIS isn't going to do much good as it is pretty much line of sight and from sea level in any swell that won't be very far. Of course with the AIS antenna at the masthead (as mine is) then that improves things.

Also it suddenly makes a lot more of the boat's equipment safety - critical. The VHF, the Plotter and all associated electronics and at present I do not regard any of those as safety-critical.

 

[LadyInBed]

I have actually been looking for something without really knowing much about them. Or making the connection its basically the same thing as a PLB.
Not for sailing. I don’t plan on falling of my boat. Who does?
I was looking for a satellite beacon which I guess is a PLB for riding my bike. I often ride some pretty lonely roads. Even People in pick up trucks disappear every year.
I don’t plan on crashing my bike either but the odds suggest it’s a lot more likely.
Choices appear to vary between subscription or no subscription. They all have to be manually operated. I was hoping there might be a kind which activate after an impact. doesn't appear to be an option.
So for a PLB to work, you have to be consious, capable of movment, fingers working, and be able to reach it.

Maybe a Tracker is more what you need like the
102-NANO GPS Tracker
no emergency alert but people will know where you are to pick up your remains!
Combine that with a GPS PLB to use if you are conscious and you have your bases covered.

 

[Daverw]

It appears to need a SIM card so no better than a mobile phone

 

[Kukri]

I have just read through this thread. I wonder if I have it right?

My provisional conclusion is:

EPIRB:

For when the boat sinks suddenly. Float free model definitely best, but not easy to find the ideal location on deck. Boat may sink due to explosion, collision, failure of stern gland or skin fitting and contact with rock or sandbank, so useful in home waters as well as in mid ocean.

PLB:

For when you are overboard and there is no way to get back on board. (Possible use in dinghy?)

AIS MOB device:

For when you go OB and there is a crew remaining on board. (Does it need to be linked to your own chart plotter?)

I think I should carry a float free EPIRB and have AIS MOB beacons fitted to each life jacket.

Is this right?

 

[FlyingGoose]

I have just read through this thread. I wonder if I have it right?

My provisional conclusion is:

EPIRB:

For when the boat sinks suddenly. Float free model definitely best, but not easy to find the ideal location on deck. Boat may sink due to explosion, collision, failure of stern gland or skin fitting and contact with rock or sandbank, so useful in home waters as well as in mid ocean.

PLB:

For when you are overboard and there is no way to get back on board. (Possible use in dinghy?)

AIS MOB device:

For when you go OB and there is a crew remaining on board. (Does or need to be linked to your own chart plotter?)

I think I should carry a float free EPIRB and have AIS MOB beacons fitted to each life jacket.

Is this right?

Seem good
I travel with an EPIRB and will be fitting AIS MOBs to the life jackets . a PLB as you say is good for single handers in any water sports

 

[duncan99210]

Kukri, I reckon that’s about right. If money and available space on the lifejacket permit, I’d like to have an AIS MOB and a PLB but I’d give priority to the AIS MOB.

 

[Iliade]

PLB will also work fine if the boat is in distress, but not for as long. I have two, one for me and one for SWMBO, so could use them sequentially if I was mid Atlantic.

They are also good for mountaineering, back country skiing, dog walking in far flung places, etc, etc. and I do like to multi-purpose my toys.

I also use a SPOT tracker (satellite based) but am considering moving to Garmin for increased functionality, albeit at slightly greater cost.

 

[Star-Lord]

I thought this had been hacked to death but things change.

Naively, it seems to me that if you suffer a MOB, the PLB will allow you to find and hopefully recover.

The EPIRB, if attached to the MOB, will not.

This seems a compelling choice to go for the PLB.

What is wrong with this simple view?

I use personal epirb and AIS in lifejacket fitted by ocean safety for myself when alone and for crew on watch when I have company. IMO if you can get both do so.

 

[Star-Lord]

Mine is spring loaded. All you need is to hold the PLB upright. It wedges between the left and right part of inflated LJ very well

Some people recommend velcro onto of lifejacket hood so velcro epirb to hood. I was advised against this because it may tear the hood.

 

[Skylark]

AIS MOB device:

For when you go OB and there is a crew remaining on board. (Does it need to be linked to your own chart plotter?)

I have the Ocean Signal MOB1 device and it is fairly easy to program MMSI number. It can be reset and/or a different MMSI number set quite easily, too so these are good for people who sail regularly on different boats.

When activated, any receiving AIS stations in the vicinity will be alerted with MOBs lat and long.

 

[Kukri]

I have the Ocean Signal MOB1 device and it is fairly easy to program MMSI number. It can be reset and/or a different MMSI number set quite easily, too so these are good for people who sail regularly on different boats.

When activated, any receiving AIS stations in the vicinity will be alerted with MOBs lat and long.

Thank you. Very helpful.