DSC Alerts - A voice speaks in the wilderness...

[DRW]

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I’m looking forward to our new AIS software coming, it turned out to be useful for SAR over the summer, ......

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Could you expand on this DRW? How is AIS so useful to SAR, particularly for recreational boats?

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Without AIS, if we had a search offshore, we would broadcast to all vessels to let them know and wait for the vessels in the area to call us back. Then they would be tasked accordingly. There has always been the suspicion (quite certainly unfounded) that perhaps not all merchant vessels respond every time.

In my part of the Channel, the large merchant ships are usually tasked to make a course alteration and make a specified track through the search area, with a good lookout posted. Once clear of the search area they are then released. Given the number of vessels in the SW bound lane this is quite useful.

Now I can look on AIS, call up the vessels that I want and talk to them directly, well before they get to the search area. I can see their position, course and speed, and negotiate the simplest but most effective track for them to follow through my search area, minimising the inconvenience and cost to them and maximising the probability of detection for me. Now I can see them transit my search area and it can all be plotted and calculated. Wonderful.

How is it useful for recreational boats with regard to SAR? Only as above I guess. I haven’t seen any recreational boats with transducers fitted yet, but I guess it will come in time as the makers get their markets and production sorted out. But who wants every one to know where they are all the time? Perhaps some will?

Hope that answers it….

 

[DRW]

Thanks Shy Talk, I will try and persuade my bosses accordingly... /forums/images/graemlins/smile.gif

 

[ShipsWoofy]

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The DSC calling for routine traffic is a bit unnecessary for calling us at Solent, as we keep a listening watch on Ch67 as well as Ch16. It is so much easier for us when someone calls us direct on Ch67 to pass routine traffic than to call us up on DSC or CH16.

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Amnesia alert, wake up and logging on, someone help me!

Anyhow, to your point above, please be clear this is a local choice, call any of the west coast CG's on their working channel without a call on 16 first and you get your wrists slapped, accept the Solent with her radio check mania is a different kettle of fish!

 

[Piers]

I started using my ICOM 610 DSC this season when calling the CG with TRs. I checked and double checked the manual before I eventually had the courage to press the button for the first time...

After a while, I had an acknowledgement, pressed the button and waited for the CG to call. They didn't. Tried again. Same response.

Called on ch16, passed the TR and asked if they'd had the DSC - yes. Hmm.

To cut the story short, I found the button needed pressing twice (once to cancel the alert, and again to go to the required channel)

But before trying again, I called the CG on the mobile to ask what they would like me to do after receiving the acknowledgement. Answer, "Call us, state your boat name, and that you are responding to DSC and give your MMSI." The MMSI is necessary since they may have had more than one DSC call and therefore need to check which you are.

Although it seemed longhanded, by the end of the season it was quick and simple to use.

However, nothing in the instruction book on numbers of times to press the button, and nothing on the DSC course that said respond when the alert is acknowledged, let alone with the MMSI as well.

Live and learn?

 

[Anonymous]

Thanks, DRW, for a full explanation.

One other point in their favour must be that it might give confidence to inexperienced sailors to be able to make contact with the CG provided they don't think that anyone will raise an alarm if they are overdue, of course! The biggest weakness seems to be that few realise that despite telling the CG that their ETA is, for example, "Dartmouth around noon tomorrow", nobody will ever check their non-arrival, even a month later. Should that be made clear at the time when people lodge a TR, I wonder?

Thanks for your excellent, clear and informed input - it is much appreciated.

 

[Bluebird]

Woodentop
I agree that some might find it easier not to use DSC for routine ship-to-ship calls but I thought the idea was to use DSC (or direct on working channel) to take the strain off Ch16 so that it freed up Ch16 for distress and urgency working only. Wouldn't that be better for you?

 

[DRW]

Ship's Woofy.

Yes you are absolutely right. I should have made it more clear.

Only MRCC Solent maintain a listening watch on Ch67 all the time. This is purely due to the high volume of chaff there is on Ch16 in our area. The objective of this open working channel is to reduce as far as possible the volume of traffic on Ch16. (Please let's not get into discussing radio checks, please).

No other HMCG station is required to maintain this open channel on VHF, and so you will need to call them via DSC or Ch16, although some stations do maintain an open working channel on MF for commercial fishing vessels.

 

[DRW]

Hello Lemain, thanks for the reply. You have raised an interesting point.

Perhaps the best place for this education is during the SRC course? I haven't done the SRC course for VHF, all my tickets are commercial so I have no idea if the SRC teaches the reasoning and workings of TRs. Does anyone have recent experience of this course. If it is missing, then perhaps it is something to be included in the course and can be recommended to the RYA for further emphasis?

 

[Skyva_2]

DRW, that's all good stuff and am learning more!

I did the SRC course last year after upgrading our VHF to DSC and don't recall the subject of TRs. I suspect it would depend on the instructor or the class raising the subject. There was a lot to get through and maybe the time would be better spent on more DSC detail such as you have provided.

However when teaching Day Skipper / YM shorebased I always cover TRs as part of passage planning, along with CG66, and make it clear we must not rely on CG to check for arrival - that's up to the skipper and shore contact.

 

[Anonymous]

Hi DRW, It wasn't made clear on the Long Range Certificate Course I took last September (AFAIR) but then most of us were pretty experienced and, I suppose, already knew. However, I have often heard people talking about TRs (overheard discussions) and it is clear that many think the CG will check non-arrival. Rather than try to introduce it into a course, couldn't the CG, when acknowledging the TR, remind the sailor with simple words such as "Roger MURW. Be advised that we do not check for your safe arrival at your destination".

Possibly much more useful use of bandwidth than the endless advertisements for DSC that most of the south coast CGs were pushing out during the first half of this year? Quite a few people have been concerned that they will not be heard on Ch16 in future and will need to get a DSC without delay which, of course, is quite untrue. It still seems to be the case that a high proportion of sailors with DSC keep their sets turned off because the alerts are too inconvenient.

Regards, David