before anyone takes the mick ..

[DRW]

Just gald you missed it Jimi. Dont worry about the position thing, it just made me chuckle watching the two lads at the Chart.

No we can't go round sinking them, shame really, no resources. What we can do is broadcast a warning when one is sighted, and then again when we get an updated position. So you did exactly the right thing. Then we have to wait for another report.

Sorry about the DSC alerts though, a real pain eh? There is a whale out there somewhere as well. Should be able to smell that in the dark though as long as you are going upwind........

<hr width=100% size=1>What is 'markup in my signature' ?

 

[Twister_Ken]

Containers and the future of offshore sailing

The US Sailing Academy (Gold Medals 'Rnt Us inc) has stated categorically that floating containers hold no fears for McDodgy 26 owners, because the movable ballast can be emptied, the swing keel (patented) swung and the flying pigs deployed to lift the noble craft clear. Quite why PBO didn't accept this conclusion remains unclear, but we can conclude that as the McGrotty 26 is a product of good old American (hands on hearts, please guys) know-how, that the Limey author was miffed that he didn't think of it first and cash in on the biggest selling boating sensation since the Liberty Ship (also an American invention, like breast implants).

<hr width=100% size=1><A target="_blank" HREF=http://www.writeforweb.com/twister1>Let's Twist Again</A>

 

[Robin]

DSC Alerts

At least Solent and probably the other CGs this side are so far at least not using the DSC alerts indiscriminately. Joburg Traffic Control put out repetitions every 20 minutes it seems, and for a request to give a deep draft vessel a wide berth. If it is a shallow draft vessel I suppose it is OK to carve them up BMW style! The problem is that the CH70 digital alert has a huge range (we got them endlessly in the Morbihan) far greater than the regular transmitter on CH80 that they switch you to, but nothing received. We were switched unnecessarily 3 times when listening to a VHF forecast that WAS important to us and was missed, only to find nothing received on CH80 it had jumped to..

Now if we could just persuade you to stop acknowledging the muppets asking for radiochecks wouldn't it be peaceful!

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[DRW]

Re: DSC Alerts

Oh yes, wouldn't it. Unfortunately there are national rules which we have to follow. We have persuaded our national Head of SAR that Solent cannot respond during the busier times on ch 16, but we must do so if it is not too busy.

I get tired of listening to it as well when out on a day off. You just can't get away from work can you?

Regards, David

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[Robin]

Re: DSC Alerts

At least we don't have to listen every day AND have an 'off' switch!

As a matter of interest though, does the CG alarm for DSC have the same non-adjustable screaming volume or do they trust you to turn a volume control knob? I guess too you hear the constant Jobourg Traffic DSC calls, are they being over enthusuastic do you you think? All off the record of course, I promise not to tell a soul!

Robin

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[DRW]

Re: DSC Alerts

Yes it screams, it is networked and so it also jumps up on your workstation in front of everything else. It does have a volume but the way it is set up it can’t be turned off. It is fair to say it is not something that can be missed. An urgency or distress alert makes a very distinctive, penetrating noise; they obviously did some research into finding just the right pitch.

We also seem to receive every CG station from Thames to Swansea, and the French from Corsen to Joburg. On a good day it can be a little further. It is a much bigger problem on the MF/HF DSC system, fortunately Solent is not fitted with that but at my last station it was non-stop.

The French are just following the ITU / IMO rules really, it is written down what you must use a DSC alert for which includes all Securite broadcasts. The HMCG version is to allow a little discretion so that if we receive some information that is vital to the mariner to receive ASAP, then we use the DSC and can use NAVTEX etc etc. But if it’s less urgent we would just go with a Securite RT Broadcast.

So for example, a DSC alert should precede a new SWW or gale warning if there is a significant change to the forecast, such as an increase in intensity of change in direction, or if it is the first warning of oncoming weather. But if it is a new warning that extends a current warning, without significant change and the winds had not been forecast to abate, then that would warrant an immediate Securite broadcast on RT but we would not necessarily use the DSC unless there was some other factor to take into account.

The idea is to minimise the alerts so they don’t get over used. We soon learnt that some skippers had worked out how to half acknowledge a call so that the machine did not keep going off.

Your point about the DSC interrupting an important forecast is very valid and I will be forwarding it onto our SAR GMDSS forum after this leave is finished.

Sorry, the short answers– Yes it is loud and screams and no we can’t turn the flaming thing off, and no the French are not overusing it in so far as they are following the rules.

All the best, David.


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[Robin]

Re: DSC Alerts

Thanks David

My guess is that the sensible use of discretion makes all the difference and I've had no cause to complain about a UK station alarm.

The interuption of a weather transmission by a DSC alert which kidnaps your radio is especially irritating as you obviously appreciate. On one occasion we 'missed' a forecast and made our decision to sail that day on the basis of the previous days forecast outlook, we were at anchor off an offshore island in South Brittanywith no access to a harbourmaster forecast. We had rather different winds than we expected, not a problem for us but 30kts of (fortunately) tail wind and thunderstorms came as a bit of a surprise, to a small boat it would have been more 'alarming'!

Robin

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[Ships_Cat]

Re: DSC Alerts

David

Are you saying that transmissions that would normally be category Safety (ie equivalent to telephony Securite), such as a gale warning update, floating obstruction, etc are being transmitted as category Urgency (ie equivalent of Pan Pan) or Distress?

Why I ask that is that from the boat end point of view Class D transceivers are required, as I understand it, to have an alarm for categories Urgency and Distress and is the loud one, and a different alarm (must be different) for categories Safety and Routine. I am talking about the ITU standard for Class D here and it may be that the UK/EU standard requires the loud alarm for category Safety as well but that would seem unlikely.

How I interpret that is if the loud alarm goes off on the boat's receiver, as Robin and others are saying, then the shore station has to have transmitted the Safety call as category Distress or Urgency instead of category Safety. That would seem counter to the intent of those categories (being the equivalent of Mayday and Pan Pan in telephony) and what should happen is the alarm be the Safety one which should be the same as that for normal Routine calls (and if it is different to the Routine call alarm, then it must still be different to the Distress/Urgency one).

Hope that makes sense.

John

<hr width=100% size=1>I am the cat but I am only 6.

 

[DRW]

Re: DSC Alerts

Oh dear, no I do not mean that, I can't have been very clear, sorry John.

A Securite RT broadcast has the DSC equivalent of Safety alert. It would not be appropriate to precede a safety message with any higher priority alert. I have not lived with the class D radio and would have to look up and the alarms on them. In the ops room, the Urgency and Distress alarms are the really loud ones, the security and routine are a little less strident. I fully agree that an ideal situation would be one noise for routine, one for safety, and another for urgent and distress alerts, but as long as the subsequent message is recieved, then the alert has done it's bit no matter what noise it makes

Our system allows us to send Distress Relay, Urgency (RT = Pan), Safety (RT = Securite), and Routine alerts. The Distress relays are by default to all stations, the others can be to all stations or an individual vessel.

If you believe that a shore station has preceded a safety message with an urgency alert, a call to the station would be in order once the higher priority traffic has ceased to clarify the alarms you are receiving. If there has been a mistake, it will help bring that to light as well.

Hope this helps. Regards, David.

Robin - yes fully understood - many thanks, an absolutely valid point. Shore stations need to know the knock on effects of an alert. The 3 times you were knocked off you forecast was probably because the shore station had to put the alert out on 3 aerials, which have to be done independantly. If the flank shore station is broadcasting its forecasts then the alerts need to be held off until the broadcast is finished. Regards, David.



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[Robin]

Re: DSC Alerts

David

Just for clarification, the 3 times we were bounced off the forecast were 3 entirely separate occasions, on different days and by the time we got below, checked the alarm was merely a repeat and switched back to the forecast's channel, we had missed it totally.

Maybe one reason for the clash between (repeat) alarms and weather transmissions is that they, like all of us work in set time chunks? By that I mean 'on the hour' or on the 'half hour' etc? French CG weather forecasts on VHF are generally recorded and go out sequentially around the coast usually with about 15 minutes between a transmission from one station and the next one down the coast, these times are published so should be known to the stations putting out the alerts. Most times if you have a set with good range this is good because you have a chance of receiving from 2 stations, even occasionally 3 though only the nearest may be clear and unbroken. This gives you a chance to fill in the gaps as you write it down or translate it into English, however if you are anchored behind high ground as we were only the nearest station gets through.

Robin

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[Ships_Cat]

Re: DSC Alerts

Yes that is how I understand it to be Dave. So what I find confusing is why when a category Safety call is made from a shore station, people are finding that the loud category Distress/Urgency alarm goes off on their boat sets. Maybe someone can correct me if I am interpreting what people are hearing incorrectly when I say that (but there have been a few PM's in the background to me on this so I think I am representing what some are experiencing correctly).

I cannot comment on the UK sets but my understanding is that the ITU requirement is that the category Distress and Urgency alarm on the boat's set has to be different to the Safety and Routine ones. For example on the Class D Icom sets the Distress/Urgency alarm is the 80 db plus screech, but Safety and Routine is a series of beeps.

So when a Safety call is made from a shore station eg floating danger, weather or what have you, one should hear a series of beeps or whatever the sets Safety/Routine alarm is, not the ear shattering scream that I undertand some say they are getting (especially from Jobourg) - on a Class D Icom set, for example one would expect to just get the beep alarm for those calls.

Perhaps there is some UK/EU requirement for the alarms that is contrary to the ITU one (I don't live in the UK/EU).

Thanks for your comments Dave.

John

<hr width=100% size=1>I am the cat but I am only 6.

 

[Robin]

Re: DSC Alerts

John

The routine alert which you refer to, does this kidnap your receiver and change you to it's selected channel? The full out screech alarms we get do take over our set, whatever channel we are on, and switches us to the channel the transmitting station choses, hence how we have missed forecasts. For example, we have been listening on 16 and a Jobourg alert has gone off and when acknowledged we find it has switched us to CH80. Similarly we have been listening to a forecast on CH79 and been bounced to CH80, sometimes only to find nothing there so presumably we were out of their voice range but not out of their DSC digital CH70 transmission range We have also been bounced from a working channel to CH16 for a Pan Pan call (from a French CG) but that is at least understandable, though when the Pan Pan is entirely transmitted in rapid French, is broken because of distance, and refers to a missing windsurfer 50mls down the coast.....

There is another question arising here, surely ALL Pan Pan calls from Coast Stations should be transmitted in English as the International language for radio? I have often wondered if there were times a Brit boat could have provided information/help but were not able to understand the transmission, where we go in summer there are hundreds of Brit boats about amongst the French. Jobourg always works in English since they deal with international shipping, but French CG of course work routinely in French, including Pan Pans.

Robin



<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[Ships_Cat]

Re: DSC Alerts

When a category Safety All Ships call is received I believe that most (but maybe not all) VHF sets will automatically change to CH16 - certainly the Icom ones and yours do. Obviously that also happens with category Distress and category Urgency too. But, as I say, my understanding is that a different alarm to the emergency alarm should sound (that being required by the ITU standard).

I don't know if it has changed recently but the ITU recommendation on operational procedures I have says ships receiving a DSC safety call announcing a safety message "should tune the radiotelephony receiver to the frequency indicated in the call" which kind of infers that the change to CH16 is not mandatorily automatic but I would not be sure on that.

John

<hr width=100% size=1>I am the cat but I am only 6.

 

[Twister_Ken]

Dear dick,

Bet you wish this one had stayed down in Davy Jones locker!



<hr width=100% size=1><A target="_blank" HREF=http://www.writeforweb.com/twister1>Let's Twist Again</A>

 

[jimi]

Do'nt bother me, to have a wee mistake exposed. Just reminds me I'm human after all. It does highlight a problem with the plotter that will be part of the briefing and will have to ensure I go through the screens carefully with the family in case of a position having to be supplied in case of a Mayday or similar. Rather the lesson was learnt like this rather in more serious circumstances.

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[Robin]

Absolutely, that is a very easy mistake to make and I believe some plotters display only one position at a time. If the cursor is 'home' on the ship's position it will display that , if the cursor has been moved even slightly then it will not stay on the ship's position and the display will show 'cursor position'. Maybe the safest thing is to press whatever key sequence your plotter requires to centre ship's position which should put the cursor back on actual position? Failing that tell the crew to read position from the DSC radio screen if you have one.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[Ships_Cat]

We are just busy trying to change the subject.

To make Jimi feel better, a few years ago here a tanker discovered that they were unexpectedly heading into a big bay towards the beach one night. Between one watch and the next they managed to get their position a degree out when reading the GPS. There was an official investigation.

John

<hr width=100% size=1>I am the cat but I am only 6.

 

[Robin]

Re: DSC Alerts

John

On our set the alarm can be stopped screeching either by pressing 'end' or 'ent'. In either case the channel is changed to whatever the calling station sending the alert has decided. So in Jobourg Traffic's case if you are listening on CH16 it will switch you to CH80, this is how we can surmise where the seemingly 'false' alarms with no voice reception on the working channel come from. Likewise we have been 'switched' on pressing 'end' or 'ent from CH79 to CH80, it is not that it always switches you to CH16 in fact in the cases I'm reporting (repeated alarms) that never happens, as yet I have not heard any Pan Pan or Mayday urgency transmissions from Jobourg, those kind of calls go out via CROSSMA, the French CG stations, they actually have one in the same place it seems 'CROSSMA Jobourg' as opposed to Jobourg Traffic Control the TSS monitoring radar station.

Robin

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[Guest]

Post deleted by danfoley

 

[Robin]

That is cruel...

Yetis have feelings too you know.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>