AIS SART vs AIS MOB

[Vronsky]

Hi All,
Your comments please:
I only sail inland waters here in Holland, mostly solo. I have a handheld VHF (non-DSC) on board.
I'm considering buying one of these AIS SART/AIS MOB beacons for emergency crisis situations (fire, sinking, collision, passenger casualty, engine failure in shipping lanes)
As I understand it, the AIS SART will send out a 'SART' text out to nearby AIS receivers, and AIS MOB a 'MOB' text. Costs are about the same.

Which one should I choose?
Somehow, I believe/expect that an MOB call might get better respons.
However, some of the above mentioned 'crisis' are not MOB, so such a call would be 'false'.

??
THANKS,
V.

 

[Buck Turgidson]

For all of the examples you list a "mayday" call on Vhf would be the most appropriate way of attracting assistance.

 

[Spirit (of Glenans)]

+1. An MOB call on VHF will alert potential rescuers . The MOB item you mention will probably emit a homing signal on VHF, which will help them to locate you, but the AIS device is only detectable by suitably equipped vessels.
While many saltwater yachtsmen now consider AIS to be essential, it's use is probably a lot less popular on inland waterways, even the quite extensive ones in Holland.

 

[Vronsky]

Thank you.
In extreme stressfull, life-threatening situations, I expect it will be very hard to explain one's GPS coordinates via VHF (thats even tough in normal times), and DSC involves protocol procedure that can be slow as well.
With AIS MOB/SART: both the distress message and position are sent out immediately. Of course, only AIS receivers will notice (just like DSC), but these days all professional vessels have this, and that's where any help most likely will come from, I think.

VHF of course remains available for all other, non-life threatening situations.

 

[Tranona]

The chances of needing that level of urgency are extremely small. Both of those devices are only intermediaries between you and the rescue services. The key is direct contact with the coastguard, not other ships or via the satellite. So VHF or even mobile phone direct to the emergency services is far and away the best method, and indeed from the statistics published by the coastguard in the UK account for virtually all the calls for assistance. The only value of those devices is if you are denied access to radio or telephone, for example if you are offshore and out of range or if you fall overboard.

Nether of these are likely to happen where you are boating and the type of boat you have. Spend your money on a good marine DSC VHF with a mic for use in the cockpit plus a smartphone, which I assume you have already. The other devices are a solution for a non existent problem (in your situation)

 

[bedouin]

As an alternative have you considered a HH VHF with DSC? They are available for the same sort of price as an AIS beacon and have the benefit of allowing you to follow up the DSC/AIS signal with voice.

There are downsides - as it is a multi-use device it may not always be fully charged and won't be "fit and forget" in the same way that a beacon is.

 

[KompetentKrew]

I would definitely favour a DSC VHF over AIS for this use.

I've seen more than one skipper dismiss the alarm when it's been blaring down below - probably because they figure the coastguard will deal with it anyway. I don't see that AIS would be more likely to attract their attention than DSC..

With a DSC radio you hit the emergency button and you can also call on channel 16. The coastguard are able to get your position by DSC - I don't know what "protocol procedure" you refer to.

 

[Vronsky]

Thank you,
This is the official DSC protocol, I believe, it involves a bit more than hitting that red button >
https://assets.publishing.service.g...1302228-001_GMDSS_sea_areas_map_FINAL__1_.pdf

 

[Tranona]

What is the problem with that? The coastguard will get details of your vessel and its location, but is unlikely to do anything without contact with you to determine what the issue is and take appropriate action. As I (and others) have said the most effective way of getting assistance is calling the rescue services direct, not just sending a signal. I have real difficulty in accepting that one would ever get to the point of not being able to do this through either VHF or mobile phone in your location. Bit different if you are sailing offshore when you need a different strategy. If you don't know how to use VHF and DSC then do the course and get you Certificate which in most countries like the UK is required before you can operate a VHF (except in an emergency). No certificate required for a mobile phone which is for inland waters as effective as VHF.

 

[Vronsky]

You sound upset: my apologies !

 

[Tranona]

No, not upset at all, just bemused by the seeming lack of understanding of the basics! Apologies if I have got this wrong.

 

[Vronsky]

Not wrong, just a little ignorant:
DSC does not work inland here.

 

[Buck Turgidson]

Not wrong, just a little ignorant:
DSC does not work inland here.

Which begs the question of why YOU brought DSC into the conversation. I assume your radio is not ATIS capable which it should be in your region. But whether it is or not is still moot for the examples you gave.

This is bang on VHF distress territory. Not MOB not AIS but good old fashioned VHF comms backed up by some flares if needed (that's a can of worms opened).

Just do a course and learn how to send a PAN and a MADAY. Much better value than buying an inappropriate electronic safety aid. I guess you fell for all the glossy advertising.

 

[Vronsky]

That's PAN PAN and MAYDAY, Buck.
But thanks for the useless comment anyway.

 

[Tranona]

That's PAN PAN and MAYDAY, Buck.
But thanks for the useless comment anyway.

Buck has offered you useful advice - exactly the same as I was about to do. Find out how to use your VHF and the set up of the local rescue services. Then you might see why your original question had some of us puzzled.

Good luck and safe boating.

 

[Buck Turgidson]

That's PAN PAN and MAYDAY, Buck.
But thanks for the useless comment anyway.

lol,
That's what you take away from the post?
Well done, with that level of pedantic knowledge one has to wonder why you asked the question in the first place as you surely know that VHF coms is the answer. .

 

[KompetentKrew]

Thank you,
This is the official DSC protocol, I believe, it involves a bit more than hitting that red button >
https://assets.publishing.service.g...1302228-001_GMDSS_sea_areas_map_FINAL__1_.pdf

That DSC doesn't work on the inland waterways makes the point moot - but your link just shows standard radio protocol.

In the UK a ship's VHF license requires you to go on a 1-day course on which you're taught how to call mayday in this way.

In reality, many boats have the mayday procedure printed on a laminated card next to the radio, so that you can remember it when in a panic or an inexperienced guest can make the call. And, in reality, the important things are that "mayday" and your position are communicated.

You might argue that it "shouldn't" work that way, but people are far more likely to come and find you if they hear someone saying "mayday" on the radio and they have a position for you, than they are if they have just have an electronic alert showing the position of a supposed emergency.

 

[KAM]

I am just about to buy an AIS beacon. Reasoning is as follows. I often sail single handed in areas of poor VHF reception. I'm not intending to replace out of date flares. I have 2 epirbs but If I need assistance I want the nearest vessels to be aware. The idea that I can press an AIS button along with the DSC distress then get on with sorting the emergency is appealing. When single handing I would dread having to call on channel 16 and spend ages answering a long list of questions, what colour is your vessel etc when I could be working on preventing my vessel sinking.

 

[Tranona]

I am just about to buy an AIS beacon. Reasoning is as follows. I often sail single handed in areas of poor VHF reception. I'm not intending to replace out of date flares. I have 2 epirbs but If I need assistance I want the nearest vessels to be aware. The idea that I can press an AIS button along with the DSC distress then get on with sorting the emergency is appealing. When single handing I would dread having to call on channel 16 and spend ages answering a long list of questions, what colour is your vessel etc when I could be working on preventing my vessel sinking.

Not sure it works like that. Sending a DSC and even less an AIS signal does not initiate any action with certainty. DSC alerts in coastal waters are largely ignored for 2 reasons, first there are too many and second few of the recipients are in a position to do anything to help. What you need to do is to establish verbal contact with those who can take action and in coastal waters this is the coastguard. A DSC short cuts the procedure by giving your position and boat details but action depends on the follow up call. Vast majority of calls are not dire emergency but requests for help at graduated levels of urgency, hence the various levels of VHF calls.

I singlehand and have only called once and just called the coastguard on VHF explained my problem and they took appropriate action. No big drama. Only a tiny number of incidents go straight to the ultimate I am sinking and dying and no amount of extra pinging will suddenly save you, despite what the hype says.

 

[KompetentKrew]

I am just about to buy an AIS beacon. Reasoning is as follows. I often sail single handed in areas of poor VHF reception. I'm not intending to replace out of date flares. I have 2 epirbs but If I need assistance I want the nearest vessels to be aware. The idea that I can press an AIS button along with the DSC distress then get on with sorting the emergency is appealing. When single handing I would dread having to call on channel 16 and spend ages answering a long list of questions, what colour is your vessel etc when I could be working on preventing my vessel sinking.

I don't think this is a bad rationale, except that IMO it comes after having a handheld DSC and an AIS transponder on the boat itself, which would fulfil the same job of allowing your boat to be seen whilst you sort things out, and which would also allow you to be seen all the rest of the time when you're singlehanding too, crossing the Channel on a foggy night or when you pop below to make a sandwich.

Also, whilst you may be in an area of poor reception from the coastguard, if you're within AIS distance of other boats you'll also be within VHF distance of them. If you're more than a few miles away then it'll take them an hour to get to you.