Combined PLB and AIS beacon

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Mister Rhino

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Rather than have to carry/wear/set off two units I have long thought that a single personal safety unit able to both act as an PLB (if solo or crew paying no attention) and a AIS marker (if they are) would be a good idea.

I believe that there were regulatory problems that blocked this idea but that they have now been removed.

At Dusseldorf this year, I saw a mock-up of a combined unit from Sea-angel, link here http://seaangel.at/index.php?language=en

Any one out there got any more information on this product or the like from more well known companies?
 
Mister Rhino said:
Rather than have to carry/wear/set off two units I have long thought that a single personal safety unit able to both act as an PLB (if solo or crew paying no attention) and a AIS marker (if they are) would be a good idea.


At Dusseldorf this year, I saw a mock-up of a combined unit from Sea-angel, link here http://seaangel.at/index.php?language=en

Any one out there got any more information on this product or the like from more well known companies?
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According to their site available Q3 2016 I am hoping to get one as soon as available!

http://seaangel.at/seaangel_sa16_plb_ais.2906.html
 
Daydream believer said:
My PLB has a gps in it. It is not connected to the boat but transmits to the community at large like any EPIRB.
Is that not the same thing?
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The difference is the AIS functionality. I have separate PLBs and AIS beacons but a combined unit would be perfect then the PLB would attract the rescue services whilst the AIS attracts all boats in the area which have AIS receivers ..... including the boat you fell off!

Richard
 
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RichardS said:
The difference is the AIS functionality. I have separate PLBs and AIS beacons but a combined unit would be perfect then the PLB would attract the rescue services whilst the AIS attracts all boats in the area which have AIS receivers ..... including the boat you fell off!

Richard
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Would not do me any good because there would be no one on the boat to turn it round & come back for me !!!

However, What happens when an epirb goes off, does it not send a DSC VHF signal out to all & sundry or is it only a signal that can be picked up by suitably equipped rescue services?
 
We're waiting on these at work as well.
The plan is for all our PLBs will be AIS in future as well, can't describe what an enormous improvement this will be over the current PLBs.
 
Daydream believer said:
Would not do me any good because there would be no one on the boat to turn it round & come back for me !!!

However, What happens when an epirb goes off, does it not send a DSC VHF signal out to all & sundry or is it only a signal that can be picked up by suitably equipped rescue services?
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No. It primarily sends a position signal to the COSPAS-SARSAT satellite network, and may also emit a homing signal for SAR assets, primarily aircraft. You might find it worthwhile to read a couple of McMurdo sites intended to explain what the different distress beacons actually do (especially as you own one) so you are not expecting a feature that isn't there! http://www.epirb.com/how_does_an_EPIRB_work.php and http://info.mcmurdogroup.com/AIS-MOB-Resource-Page.html
 
Perhaps I'm being stupid here but I don't get the fascination of these combined units.

I for example have an Ocean Signal AIS attached to the air filling tube on my lifejackets; it's as small as the emergency light and nobody would ever guess it was there. I also have a PLB fitted to the same jackets and that's slightly bigger.

Is the immeasurably small convenience advantage of a combined unit not outweighed by a potentially bigger reliability advantage in being sure that at least one will work? Unless I suppose the combined unit comes in way cheaper.
 
dom said:
Is the immeasurably small convenience advantage of a combined unit not outweighed by a potentially bigger reliability advantage in being sure that at least one will work? Unless I suppose the combined unit comes in way cheaper.
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The chips themselves are probably not expensive so the cost is in the encapsulation. A combined unit should be much cheaper that two separate units once there is some competition in the market.

Richard
 
dom said:
Perhaps I'm being stupid here but I don't get the fascination of these combined units.

I for example have an Ocean Signal AIS attached to the air filling tube on my lifejackets; it's as small as the emergency light and nobody would ever guess it was there. I also have a PLB fitted to the same jackets and that's slightly bigger.

Is the immeasurably small convenience advantage of a combined unit not outweighed by a potentially bigger reliability advantage in being sure that at least one will work? Unless I suppose the combined unit comes in way cheaper.
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+1

The two systems have separate but complementary functions.

The PLB transmits a signal, usually with a gps position, to the satellite network, alerting shore based rescue service as to where you are. Global coverage but the signal is not received by nearby vessels.

The AIS beacon transmits a VHF distress signal, the same signal you get by pushing the red button on the VHF set. It transmits to all local DSC and AIS equipped vessels within range. It does not alert shore based rescue services unless you happen to be close inshore and they can receive the signal. Bear in mind that VHF is line of sight, so a beacon attached to a lifejacket will not be received as far away as a signal sent from you masthead antenna.

At present, I'm content with just having PLBs on board as we don't have AIS and therefore have no way of tracking a MOB via an AIS beacon. When (if) we get AIS, then I'll look at adding AIS beacons to the inventory. But they'll be separate units not dual purpose.
 
prv said:
No it doesn't.

Pete
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Correct, it is over the VHF frequency but will only be picked up by those with AIS receivers, in addition most older AIS receivers will not do anything other than just show another "vessel" on their screen, only much newer ones are programmed to sound an alarm and show a visual indication of which "vessel" is in distress.
 
Colvic Watson said:
Correct, it is over the VHF frequency but will only be picked up by those with AIS receivers, in addition most older AIS receivers will not do anything other than just show another "vessel" on their screen, only much newer ones are programmed to sound an alarm and show a visual indication of which "vessel" is in distress.
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Not quite, modern personal AIS beacons also have the ability to activate the DSC alarm on the mother ship (vessel's MMSI is programmed into the beacon) and thereby alert the crew to the fact that someone has fallen off. This will be in addition to any AIS alarms which may have been triggered.
 
dom said:
Not quite, modern personal AIS beacons also have the ability to activate the DSC alarm on the mother ship
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I would say that's then a combined AIS and DSC beacon.

COSPAS-SARSAT, AIS, and VHF DSC are three independent systems. There are various combination transmitters available (plus at least one that also does VHF voice with a recorded message!) but the technologies are still separate concepts. I'm always a bit bemused at how many people (not you :) ) seem to mix up and conflate them with each other. It feels a bit like the guy I sailed with who was annoyed that his mobile phone didn't work a couple of hundred miles west of Biscay, because "the satellites should be everywhere". He had no idea of the difference between a mobile and a satphone, and was sceptical when I tried to explain about the mobile phone masts scattered around the country but conspicuously absent in mid-Atlantic :)

Pete
 
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dom said:
Not quite, modern personal AIS beacons also have the ability to activate the DSC alarm on the mother ship (vessel's MMSI is programmed into the beacon) and thereby alert the crew to the fact that someone has fallen off. This will be in addition to any AIS alarms which may have been triggered.
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That sounds interesting. Can you post a link to an AIS beacon which transmits a DSC signal as I've never seen one advertised?

Richard
 
RichardS said:
That sounds interesting. Can you post a link to an AIS beacon which transmits a DSC signal as I've never seen one advertised?
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http://oceansignal.com/products/mob1/

I was considering getting one, as much for the compact case and long battery life as for the DSC feature, but I think I'll now wait for a decent combined AIS / PLB.

Pete
 
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dom said:
I for example have an Ocean Signal AIS attached to the air filling tube on my lifejackets; it's as small as the emergency light
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You must have huge emergency lights. Apparently the MOB1 is nearly 14cm long.

I looked into doing the same as we have FastFind 220 PLBs inside all our LJs but along with a sprayhood and light on one side (bayonet fitting and bottle on the other) there was no space even for the MOB1, which is why I'd be interested in a combined unit which I guess won't be much bigger than the PLB. Where are you stowing your PLB, inside or outside the jacket? we found them inconvenient when stowed on the harness, and in discussions with a pal who is also DLA/sea safety officer at the local station, concluded they'd probably be inaccessible when overboard anyway, which is why they are inside the jacket.

I am considering putting an AIS beacon inside our son's LJ instead of the PLB, because even though he's 10 now I wouldn't trust him to fire a PLB and the AIS beacon is automatic. If he fell overboard it would a) allow us to report his position to the emergency services and b) stand a good chance of recovering him ourselves.
 
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