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Old 17 November 2013, 06:32   #21
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Hi again - missed one last thing on the lifejacket. We also have a Firefly Strobe lights - this is a high intensity flashing light - clearly seen by day but particularly at night.

All of these items are expensive but, as many on the forum point out, there is nothing like having them if you get into trouble. For boats with big engines it probably equates to a few fuel fill ups!
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Old 17 November 2013, 08:49   #22
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The whole system works on a distress signal being sent to a satellite and then that signal being resent to earth to an earth station. So if a signal for distress goes off in the UK the ping may first be picked up in say Portugal.The average time for a response in 45 minutes and it can take as long as one hour.
There seems to be a fair amount of misinformation about PLBs and EPIRBs out there.

Original EPIRBs couldn't/didn't send positional data. That meant they sent signal that basically said "My boat is XYZ, I'm in Distress" and the the satellite system tried to work out where the boat was which was typically to a 5km area. That information is then relayed to the Coastgaurd for the country of origin for the EPIRB. They will then try and contact the vessel - landline call to the registered owner to exclude false alarm. VHF call to the sector its in based on the 5km area. The 5km satellites can take up to half an hour to fly overhead in most of the places we operate. That means a response will typically take 45minutes before all the bells and whistles are properly kicking off. The fact that the satellite that receives it beams it to portugal should make seconds of difference rather than half an hour. Its the fact that the satellite that needs to work out where the boat is needs to fly roughly over it to get that info and that means you have to wait.

Modern EPIRBs and PLBs include a GPS and so the message it sends is basically "My boat is XYZ, I'm at position ABC, I'm in Distress. They send that to a different satellite. So if the PLB has a position in it (see below), the signal should be in Falmouth (where all UK signals are sent to) within minutes.

Snag is having the position. A GPS takes a bit of time to get a fix, especially if its not been on for a while (or ever) or if its moved position significantly. Most of the time thats only 3minutes or so. A PLB will start transmitting a positionless distress message during that 3minute period. It should then switch to with a position and help should be scrambled pretty quick. MustRIB says that took nearly 30minutes to get a fix for him. No idea why - position of the receiver I suspect.

However if your handheld DSC VHF, AIS PLB and EPIRB PLB were all in a head to head test with a cold GPS fix then the time difference in putting a meaningful position on the chart plotter of your local coastie isn't going to be massively different in my opinion. The snag is switching your EPIRB PLB on to get a fix prior to going out drains battery, its not a rechargable thing. Second snag is the DSC VHF if you wear it switch off but put it on long enough before going out will store the old position. There will be an algorithm in the set that decides if it sends a position when you hit big red button based on age of the position but it may mean if you dont get a decent fix quickly it sends an old fix. The fix will be time stamped but bearing in mind a RIB travels at 30kts an hour old fix could send help looking in a crazy location.

Not sure how the AIS PLB is powered and if it can update its GPS fix constantly or just when you hit the panic button...
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Old 17 November 2013, 09:42   #23
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Here is a timeline transcript of a well known accident that happened recently off the coast of Ireland. Bear in mind the vessels involved were equipped to the highest standards and the peopled involved were extremely experienced. Note here the exact timings the PLB's were turned on at 17.45 - 17.50 The pings were not seen by anyone until 18.29. People were in the water and a mayday was not declared until 19.30. In cold water they would probably have been dead. If anyone had an AIS or a VHF the rescue would have begun immediately. The facts of this bear disaster have been analysed carefully and like any accident there are a chain of events. What rests with me is that PLB / EPIRBS are subject to delays I would not be comfortable with if I needed immediate help.

Full info on this particular accident here.

http://www.cruisingclub.org/pdfs/saf...ry_rambler.pdf


est 1745-1750 BST - both PLB's (on top of the boat) were turned on.
 about 1809 BST - ICAP LEOPARD (another 100 ft maxi) passed 3-400m to leeward. All efforts to hail or
otherwise alert them failed.
 about 5 min later - two Volvo 70's (GROUPAMA and ABU DHABI) and later an IMOC 60 sailed by to leeward.
All efforts to hail or alert them failed.
 1829 BST (about 39-44 min after 2 PLB's were activated) Valentia Maritime Rescue Sub-Center (MRSC)
received data confirming the location of the person registered as holder of both PLB‟s. At first the call over
VHF was "Gigi Bernard competing in the Rolex Fastnet Race", who was thought to be a crew member of one
of the French mulithulls in the race. Later, with the help of another race boat's (ICAP Leopard) navigator "G.
G. Bernard" was determined to be the Point of Contact for "George David" and connected him to the race
boat RAMBLER 100 which was no longer showing on AIS. (all of RAMBLER's PLBs were registered to "George
David"). Rambler‟s sat phone number was given to MRSC Valentia by ICAP Leonard‟s navigator.
 1851 BST PAN PAN Declared by Valentia MRSC. Baltimore RNLI Lifeboat dispatched from Fastnet Rock where
they were taking photos of boats and sent to the PLB position to search for an individual PLB (Gigi Bernard).
 1930 BST - after trying to call RAMBLER's Sat Phone and getting no answer a MAYDAY was declared by
Valentia MRSC. Two helos and local craft assigned to the search.
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Old 17 November 2013, 10:02   #24
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I was told that AIS PLB is the choice for a high population of shipping area with good VHF coverage. - Solent fits this!

It will show up in the coastguard and port authority AIS system almost instantaneous.

PLB good for remote locations or Western Isles due the terrain ....plus you can use it for hillwalking skiing etc.

I current have:

dsc h/h radio - m91d on lanyard
McMurdo 210 GPS PLB with flotation collar
Lifejacket light
Serrated Safety Knife on lanard
Leatherman charge
Rescue Laser Flare - shameless plug!
Fenix LED torch

I don't do much night time running but have extra strobes If needed.

when the 210 expires - I prob buy an AIS PLB instead - I have both dummy units I show on course - and like the S10 for ease of deployment .

regards
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Old 17 November 2013, 10:23   #25
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Scott -what's the advantage of AIS PLB over a handheld DSC VHF? That will show up on every DSC set - and I think there are more of them than AIS equipped plotters. And anyone who has an AIS equipped plotter has probably also linked the NMEA out of the DSC to their plotter?

Same range in principle.

Rechargable VHF so your GPS fix should be fast as you can let it fix at start of journey while on charger.
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Old 17 November 2013, 10:50   #26
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Scott -what's the advantage of AIS PLB over a handheld DSC VHF? That will show up on every DSC set - and I think there are more of them than AIS equipped plotters. And anyone who has an AIS equipped plotter has probably also linked the NMEA out of the DSC to their plotter?

Same range in principle.

Rechargable VHF so your GPS fix should be fast as you can let it fix at start of journey while on charger.
I think you are right in both cases. But my biggest concern is the always relationship between the speed of any incident and resultant ability to call for assistance. In a RIB the worst case scenarios are a high speed collision, capsize, sinking, fire, loss of crew overboard. One has to consider how to send a call for assistance if the normal avenues are prevented - which they often are in a bad incident. I like the idea of having the rescue items attached to yourself. Will a console fitted VHF work if the craft is inverted for example? I would not wish to unduly worry Lisa's regarding her original query. A major incident on a RIB is unlikely and happens rarely - being prepared and having a good VHF understanding is a major step forward.
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Old 17 November 2013, 10:52   #27
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Scott -what's the advantage of AIS PLB over a handheld DSC VHF? That will show up on every DSC set - and I think there are more of them than AIS equipped plotters. And anyone who has an AIS equipped plotter has probably also linked the NMEA out of the DSC to their plotter? Same range in principle. Rechargable VHF so your GPS fix should be fast as you can let it fix at start of journey while on charger.
Belt n braces - not every body has there DSC radio on a two way link to plotter - I know prob less have AIS transceivers and those who have have DSC connected ...BUT ONLY a coastie have access to PLB signals ...

I have DSC hand held - my area of normal cruising i feel I don't need PLB for reception - carried as back up.

I believe the AIS PLB suites MY needs better as an additional method of contact rather than PLB. The two types one that can be added to life jacket and deploy automatically and S10 type both show in the link above.

I don't want it to activate WHEn I fall in harbours! so I think s10 is the option. So DSC radio handheld and AIS PLB is the way am thinking is the way forward for ME.

I also have the nautilus divers radio too !

I have collected radios to show folk on courses , also have a Dummy PLBs , AIS PLBs and Epirbs etc for students to see on course.

If my needs change and PLB comes back into to mix...

S.
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Old 17 November 2013, 10:56   #28
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Belt n braces - not every body has there DSC radio on a two way link to plotter - S.
Not ALL radios have a Send / Receive Function for plotter comms, some are only "Listners"
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Old 17 November 2013, 10:59   #29
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Not ALL radios have a Send / Receive Function for plotter comms, some are only "Listners"
yes - I know that ...
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Old 17 November 2013, 11:19   #30
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to answer the OP question - I would buy DSC handheld Radio before PLB or AIS PLB in your area.

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