Personal Locator Beacon - or what?

[prv]

Couple of videos...

Demonstrating auto activation:



Note that they have some older plotter firmware (it was a few years ago!) so the beacon merely looks like a ship. On something more modern like my Vesper unit, for example, it would set off an alarm, pop up a box saying "MOB ACTIVE", display the target as an IMO beacon symbol (cross in a circle), and give you a range and bearing to steer to.

And a bit more technical info from the makers:



And no, I'm not on commission

Pete

 

[ctva]

Having looked at the McMurdo 220 and Kinnard Safelink, I cannot see if the McMurdo has a replaceable battery or if either is user replaceable and what the battery is. Any infor would be welcome.

 

[prv]

Having looked at the McMurdo 220 and Kinnard Safelink, I cannot see if the McMurdo has a replaceable battery or if either is user replaceable and what the battery is. Any infor would be welcome.

They're not user replaceable. I'm not sure they're replaceable at all.

All new PLBs have gone this route. A user-replaceable battery module makes the whole thing much bulkier, and the drive is for compactness to make them easier to wear. With a six or seven year service life, by the time the battery needs replacing the technology will have moved on and new ones will be even smaller and more advanced, so most of us will be happy to upgrade anyway. At £32 per year (£190 over a six-year life for the McMurdo) I wouldn't consider that it owed me anything at the end of that period.

Right decision in my view.

Pete

 

[mm42]

For the amount of room the modern devices take up and the decreasing costs now you can double up.

I wear a spinlock deckvest and inside it have installed the little kannad AIS unit set to auto activate on inflation of the lifejacket. On a belt pouch I've got a PLB. It's belt and braces but for less than £500 I've got two more chances of getting recovered from an incident at sea, whether it be a MOB or loss of the vessel.

 

[Piers]

For the amount of room the modern devices take up and the decreasing costs now you can double up.

I wear a spinlock deckvest and inside it have installed the little kannad AIS unit set to auto activate on inflation of the lifejacket. On a belt pouch I've got a PLB. It's belt and braces but for less than £500 I've got two more chances of getting recovered from an incident at sea, whether it be a MOB or loss of the vessel.

Can I ask a qn? Let's say you fall in and are rescued by your own boat within a matter of minutes. How do you cancel the PLB's distress signal?

 

[mm42]

Can I ask a qn? Let's say you fall in and are rescued by your own boat within a matter of minutes. How do you cancel the PLB's distress signal?

With the AIS unit you just reclip the top on. With the PLB there is a cancel button. In either circumstance I'd make a VHF call to the coastguard explaining the situation and that it had been resolved so as to avoid them deploying SAR assets unnecessarily.

 

[RAI]

Can I ask a qn? Let's say you fall in and are rescued by your own boat within a matter of minutes. How do you cancel the PLB's distress signal?

IIRC you then need to phone an MRCC, tell them your details and only switch off the PLB after they tell you to do so.

 

[Piers]

IIRC you then need to phone an MRCC, tell them your details and only switch off the PLB after they tell you to do so.

So if you aren't in radio contact you wait until the RNLI/SAR personnel turn up?

 

[prv]

With the PLB there is a cancel button.

I'm sure it's what you meant, but to be clear, it's an "off" button rather than a "cancel" button. That is, it stops any more signals being sent, but it doesn't do anything to cancel the alert. As you say, it needs to be accompanied by a call to the Coastguard to cancel the distress situation. I'm not certain, but I think technically it's meant to be a Securité call, and they do say you should wait until they tell you before switching off. I'm not sure why, I guess it's to avoid any possibility of mixing up two incidents and cancelling the alert for someone who's still in trouble and their PLB has just stopped working.

Pete

 

[RAI]

So if you aren't in radio contact you wait until the RNLI/SAR personnel turn up?

If the COSPAS/SARSAT satellites picked up your PLB signal before it gets switched if off, the rescue services will be coming (hopefully), as maybe your PLB just stopped working but your still in danger. If you sail on with your PLB still working, they will get faster to your position and then you can inform them.

 

[prv]

So if you aren't in radio contact you wait until the RNLI/SAR personnel turn up?

The 406MHz beacon system is part of the GMDSS, and one of the principles of that system is that you have communication with the shore at all times. The further from the coast you sail, the more kit you're required to have in order to achieve this. So as a GMDSS-compliant merchant vessel, you'd always be able to report a false alarm.

I suspect the case of non-GMDSS-compliant leisure vessels with no other long-range comms wasn't really considered in the design of the system.

Pete

 

[davidwf]

I just purchased an Oceansignal MOB1 it is a AIS SART plus it sends DSC MOB alerts to your own vessels MMSI or MMSI group, on activation. You can override and send a DSC all ships MOB by manually pressing the power button for 5 seconds.

I mostly sail single handed and generally there are commercial vessels and other leisure craft within a few miles so I reckoned it was probably better for me than an EPIRB as its directly signals boats in my vicinity rather than the rescue co-ordinatiors.

Nicely made device that clips to the top up tube of your lifejacket and automatically switches on when the jacket inflates.

 

[Piers]

I just purchased an Oceansignal MOB1 it is a AIS SART plus it sends DSC MOB alerts to your own vessels MMSI or MMSI group, on activation. You can override and send a DSC all ships MOB by manually pressing the power button for 5 seconds.

I mostly sail single handed and generally there are commercial vessels and other leisure craft within a few miles so I reckoned it was probably better for me than an EPIRB as its directly signals boats in my vicinity rather than the rescue co-ordinatiors.

Nicely made device that clips to the top up tube of your lifejacket and automatically switches on when the jacket inflates.

Now that sounds really sensible. I'll check it out - thanks for the heads up.

 

[Piers]

I just purchased an Oceansignal MOB1 it is a AIS SART plus it sends DSC MOB alerts to your own vessels MMSI or MMSI group, on activation. You can override and send a DSC all ships MOB by manually pressing the power button for 5 seconds.

I mostly sail single handed and generally there are commercial vessels and other leisure craft within a few miles so I reckoned it was probably better for me than an EPIRB as its directly signals boats in my vicinity rather than the rescue co-ordinatiors.

Nicely made device that clips to the top up tube of your lifejacket and automatically switches on when the jacket inflates.

Just looked at the product and I like the way it not only transmits an AIS MOB alert, but also an individual DSC alert to your boat's radio with the option to transmit a DSC alert to all vessels.

I was about to order two Kannad units, but will call Oceansignal tomorrow to talk the MOB1 through. Also like the look of their EDF1.

 

[Nick_H]

I just purchased an Oceansignal MOB1 it is a AIS SART plus it sends DSC MOB alerts to your own vessels MMSI or MMSI group, on activation. You can override and send a DSC all ships MOB by manually pressing the power button for 5 seconds.

I mostly sail single handed and generally there are commercial vessels and other leisure craft within a few miles so I reckoned it was probably better for me than an EPIRB as its directly signals boats in my vicinity rather than the rescue co-ordinatiors.

Nicely made device that clips to the top up tube of your lifejacket and automatically switches on when the jacket inflates.

If a PLB signal is sent and received, then surely whoever is coordinating the rescue will also be able to identify ships in the area by checking AIS, and can contact them to request they assist if prv says they can always be contacted even out of VHF range, plus you'll also know that someone trained in SAR is on the way, rather than relying on an unknown ships crew. Wearing both seems a good idea for a single handed offshore sailor, but if I only had one I think I'd choose a PLB. I wonder how long before someone markets a wearable device that uses all the available technologies in one unit.

 

[prv]

you'll also know that someone trained in SAR is on the way, rather than relying on an unknown ships crew. Wearing both seems a good idea for a single handed offshore sailor, but if I only had one I think I'd choose a PLB.

For singlehanded use you want a PLB, no question. But the point of an AIS unit is to be recovered by your own boat, not "an unknown ship's crew". An AIS beacon is a rubbish way of making a general call for help, but it's fantastic for the crew left on board who've just lost sight of Fred behind a large wave. Completely different use cases.

Pete

 

[davidwf]

If I was sailing Offshore then yes a EPIRB is best bet but as I sail inshore I am happy that a AIS SART transmission or DSC all ships MOB will attract attention its very very rare that I cannot see a ship or another pleasure craft.

If I am offshore then I have crew so the DSC alert to my own boat coupled with the AIS alarm on the plotter will give us a sporting chance of recovering the MOB.

Its horses for courses.

 

[gjgm]

Couple of videos...

Demonstrating auto activation:



Note that they have some older plotter firmware (it was a few years ago!) so the beacon merely looks like a ship. On something more modern like my Vesper unit, for example, it would set off an alarm, pop up a box saying "MOB ACTIVE", display the target as an IMO beacon symbol (cross in a circle), and give you a range and bearing to steer to.

And a bit more technical info from the makers:



And no, I'm not on commission

Pete

Just as I was thinking how nice and small these things are I reads review saying,great in a t,shirt with video crew, but try using the thing when your hands are wet shaking and cold.Then maybe you want Big...

 

[prv]

try using the thing when your hands are wet shaking and cold.

That's exactly why it's activated by pulling a tag on the end of a string, as shown in the second video.

Or the string is hooked around the bottom of the lifejacket bladder, so that it gets pulled as the bladder expands and you don't need to do anything at all, as shown in the first video.

Pete