Have Epirb's been superseded by the Personal Emergency response beacons?

[NorthPacific]

Hi Paul,

Back in post 14 the Arc I posted did state that battery life was expected to be 36hours at minus 20c and longer at higher temps. As we would have one each that would give us 72 hours min of continuous and much longer as you turn off and on in 30min intervals

Also not so much a question of cost, practicality and function as well.

Epirbs tied to boat. These would be tied to us. Paul where did you get your information on solid surface stuff. That would make them useless for my puposes?

[Paul Elliott]

Originally Posted by NorthPacific

Hi Paul,

Back in post 14 the Arc I posted did state that battery life was expected to be 36hours at minus 20c and longer at higher temps. As we would have one each that would give us 72 hours min of continuous and much longer as you turn off and on in 30min intervals

Also not so much a question of cost, practicality and function as well.

Epirbs tied to boat. These would be tied to us. Paul where did you get your information on solid surface stuff. That would make them useless for my puposes?

Perhaps I expressed myself poorly. What I was trying to say is that the PLBs don't automatically float or otherwise orient themselves. You either need to hold them with the patch antenna facing up, or you need to set them down on something (so the antenna points up). If you are treading water, with the PLB on a lanyard, it's not going to be properly oriented unless you are holding it.

This is of course in contrast to an EPIRB, which floats in the proper orientation.

Some PLBs have a flotation jacket, but this just keeps it from sinking.

The Coast Guard says you should *not* turn off the PLB or EPIRB once it has been activated. I'm not sure why, other than because they don't want to lose you.

[goboatingnow]

The Coast Guard says you should *not* turn off the PLB or EPIRB once it has been activated. I'm not sure why, other than because they don't want to lose you.

So as to not cause a situation where they cannot repeat and verify the acquisition of the EPIRB. In the event of an accidental activation you are supposed to contact them and they will tell you then to turn it off.

Dave

[Caracal]

Originally Posted by NorthPacific

Hi Paul,

Back in post 14 the Arc I posted did state that battery life was expected to be 36hours at minus 20c and longer at higher temps. As we would have one each that would give us 72 hours min of continuous and much longer as you turn off and on in 30min intervals

Each one would go through the same initial process, going through all the stages of calling people on the list and so on. It won't be like swapping the batteries.

I hate to say this, but you seem adamant picking an inferior product and coming up with solutions that will sort of make it work, even if you end with an inferior solution for more money:

Also not so much a question of cost, practicality and function as well.

More:

Epirbs tied to boat. These would be tied to us.

Keep it in your grab bag if you don't want it tied to your boat. But even if you do have it tied to the boat (that's a good thing, it won't go missing), you don't want to leave the boat until stepping up into the raft. You then bring it with you into the raft.

Paul where did you get your information on solid surface stuff. That would make them useless for my puposes?

They need to be kept pretty much upright to be able to contact the satellites. An Epirb does this by floating upright.

[Mike OReilly]

Originally Posted by goboatingnow

http://www.navcen.uscg.gov/pdf/gmdss...s_Mar_2011.pdf

leaving aside DSC false alerts which are particularly high in the US , it would seem that about 10% of EPIRB alerts are real .

Thanks for this Dave. This is great. I'll spend some time analysing the data, and share what I determine. A cursory glance indicates an overwhelming level of false positives. On the surface, this leads me to question the efficacy of the system ... unless it is me that needs rescuing .

[goboatingnow]

Originally Posted by Mike OReilly

Thanks for this Dave. This is great. I'll spend some time analysing the data, and share what I determine. A cursory glance indicates an overwhelming level of false positives. On the surface, this leads me to question the efficacy of the system ... unless it is me that needs rescuing .

I'm involved with the RNLI. There are many false alerts , not only as a result of lack of knowledge , incompetence or plain malevolence. And its not limited to electronic methods.

But today most electronics alerts are verified first, Epirb alerts are checked etc, so the actual number of false alerts that generate rescue efforts are reasonably limited. But our rescue services would always prefer to respond and not have to rescue anyone , rather then second guess the system and have a person die.

I don't really think you can judge a rescue system in any way by false positives ( even real rescue assts deployed types of positive) these people know the situations and ate extensively trained and provided with the best of equipment. They want to respond.

Dave

[Dos Gatos]

Originally Posted by nimblemotors

..transmit a digital burst once every 50 seconds.

Particularly with a GPS enabled device, how far can you move in 50 seconds?
every 5 minutes seems frequent enough, so 5x the time, 5 days, not 24 hours.

That's what I was thinking. If I had the presence of mind, cycle the plb once an hour for a few minutes. Documentation on my ARC unit suggests gps takes a bit of time to acquire satellites in order to send a fix. If the cycle was consistent, it might not appear to be accidental.

My PLB is currently registered as being on my boat but I could edit the registration to take it backpacking.

Clips on a vest. I consider it insurance for singlehanding when I might slip off the deck.

[goboatingnow]

Originally Posted by Dos Gatos

That's what I was thinking. If I had the presence of mind, cycle the plb once an hour for a few minutes. Documentation on my ARC unit suggests gps takes a bit of time to acquire satellites in order to send a fix. If the cycle was consistent, it might not appear to be accidental.

My PLB is currently registered as being on my boat but I could edit the registration to take it backpacking.

Clips on a vest. I consider it insurance for singlehanding when I might slip off the deck.

No that's not the recommended procedure. Generate the alert and keep generating the alert continuously for as long as possible. Don't 2nd guess the operation of the system and the rescue SOPs. Keep a waterproof VHF handy for the arrival of the Rescuers

Note a proper Epirb contains a 121mhz signal for use by the rescuers to home in on using directional equipment. PLBs don't do this.

Dave

[Mike OReilly]

Originally Posted by goboatingnow

I'm involved with the RNLI. There are many false alerts , not only as a result of lack of knowledge , incompetence or plain malevolence. And its not limited to electronic methods.

But today most electronics alerts are verified first, Epirb alerts are checked etc, so the actual number of false alerts that generate rescue efforts are reasonably limited. But our rescue services would always prefer to respond and not have to rescue anyone , rather then second guess the system and have a person die.

I don't really think you can judge a rescue system in any way by false positives ( even real rescue assts deployed types of positive) these people know the situations and ate extensively trained and provided with the best of equipment. They want to respond.

Thanks Dave, I think I understand your point. I'm not trying to examine the system from the provider end, but from the user side. Following along the lines of this thread, I'm asking the question as to whether we can determine the efficacy of the various emergency-response devices from those who are buying them. Fundamentally, it's a rational risk-assessment that I'm trying to get at -- from the user's standpoint, not the provider's.

IOW, how good are the various tools at actually resulting in a successful rescue?

[goboatingnow]

One cannot really evaluate the usefulness of a particular piece of technology , rather you have to put it into context in relation to its effectiveness within the whole GMDSS system. The feedback from GMDSS Is that rescue actions are now almost 100% successful , ie very few events occur that don't get alerted , even if the actual attempt itself fails.

Mandatory carraige in SOLAS vessels, GMDSS , coordinated MRCC actions and AMVER etc have now meant that very few incidents occur without being detected. The average wait in a liferaft is now 4days and events like Steve Callaghan epic trip are almost unheard off.


For offshore cruisers, adhering to the GMDSS carriage requirements even if non compulsory is the best bet IMHO.
Dave

[roverhi]

From experience, SPOTs have limited coverage areas. Coverage ends a couple hundred miles north of Hawaii and south, for one . If you are depending on a SPOT carefully check their coverage. Believe you'll need a relay to the CG to call them out. Hope someone is home to do it.

Turning an Epirb on and off could put you in the running for the Darwin Award. A non GPS Epirb has to triangulated from several satellites to get a fix. Can take bit of of time for them to figure out where you're at. Turn on an Epirb for a short period of time and the CG might not get a fix and also think it is some cretin playing games with thei weird looking plastic thingy they came across Might take quite a few hours before they took you seriously and never if you aren't very regular in cycling your transmissions. A GPS equipped Epirb will take some time to lock on. Better be sure that you leave it on long enough.

For me, I have a PLB and two Epirbs. The PLB is just in case I fall overboard and backup if something happens on the boat. I sail far offshore and want plenty of transmission time on the Epirbs because it may take a while for help to arrive.

[Dos Gatos]

Originally Posted by goboatingnow

No that's not the recommended procedure. Generate the alert and keep generating the alert continuously for as long as possible. Don't 2nd guess the operation of the system and the rescue SOPs. Keep a waterproof VHF handy for the arrival of the Rescuers

Note a proper Epirb contains a 121mhz signal for use by the rescuers to home in on using directional equipment. PLBs don't do this.

Dave

Thanks for the advice. I'll keep that in mind.

this is the unit I carry AquaFix PLB | ACR ARTEX

gps, 121.5 homing, advertised 20-36hr battery. 24 hr nominal

[Paul Elliott]

Originally Posted by goboatingnow

Note a proper Epirb contains a 121mhz signal for use by the rescuers to home in on using directional equipment. PLBs don't do this.

Yes they do. My ACR AquaLInk PLB generates the 121.5 MHz emergency homing beacon. I believe all modern PLBs do this. It also contains a built-in GPS.

For what it's worth, when at sea my boat carries two GPIRBs, and we crew are wearing PLBs.

[jackdale]

Originally Posted by Jimbo485

Why not just cut the umbilical cord with your nanny states? Refuse to have any ability to communicate with SAR. Die like real sailors or save your boat! Don't expect others to risk their lives to save your miserable skin!

AMVER vessels are not risking their lives when they rescue you.

Participation in Amver is free, voluntary, and open to merchant ships of all flags. Participation is generally limited to ships over 1000 gross tons, on a voyage of 24 hours or longer. Recently, however, enrollment has been expanded to accommodate vessels outside the normal criteria, such as cruise ships, research vessels and fish processors.

Amver.com - Automated Mutual-Assistance Vessel Rescue System - Home

The boat that came to our assistance was an 1100 foot container ship.

[S/V Alchemy]

Originally Posted by NorthPacific

Hi Alchemy,

So from a buyers standpoint what is the difference? Or are epirbs like music cd's, a brilliant advancement in their day, but now dated and surpassed by a newer format provider? Unlike the Luddittes who faced a change after hundreds of years of stability, change now happens very quickly. Is this such a scenerio?

I agree about the liferaft. It's on the list of stuff I buy in the last two weeks before pushing off...along with a crate of rum.

The differences have been covered, but I would sum them up like this:

a) EPIRBs are for the boat and PLBs are for the person. The boat goes down, the EPIRB starts beeping. It's an automatic MAYDAY. The PLB is not a MAYDAY, although you could radio a MAYDAY from the (undamaged) boat and the PLB, which should be the newer kind that transmits a lat/lon, will aid recovery if you are inshore. Between the Marquesas and Panama, tough titty.

b) the newer EPIRBs and PLBs transmit not on the old and superannuated 121 Mhz frequency, but on the newer 406 Mhz frequency, which is now monitored, so you get that benefit. I understand the higher frequency is easier for satellites to detect and relay to the UK and US and Canadian COSPAT/SARSAT orgs. See: Distress radiobeacon - Wikipedia, the free encyclopedia

c) Modern EPIRBs (which are registered) send in a similar manner to satellite phones a great deal of information related to their registry. If a signal is picked up, your contact number (which should be a third party's cell phone or something other than an empty house!) can confirm that "yes, North Pacific last said he'd been getting liquored in Too Far Lagoon, and if you have an EPIRB signal centered on a nearby reef, it's almost certainly real...and his boat." This ability to rule out a false alarm AND to send I.D. (similar to having an MMSI number for the DSC calls and the AIS I.D.) is very helpful in getting help to you sooner.

Others have pretty well covered it off. Coastal sailors don't need them so much, really, because a MAYDAY RELAY or even a cell phone call can often invoke help, but over the horizon is another matter.

Hope this helps. Read the Wikipedia entry: the advantages are clearly listed.