The (Official) "Lets Bash the Nina Thread" - sponsored by Bazzer :-)

[psneeld]

Originally Posted by svmariane

Regarding EPIRBs:

I quoted (somewhere above) info from the FCC to erase any question about Nina's EPIRB and its being "updated" or not having a bearing on SAR efforts. No EPIRB signal was reported, known or unknown. Does anyone dispute that?

Note: Before you hit the keyboard, I'm talking EPIRBs in this post - I'm NOT evaluating the pro and con of AIS vs EPIRB vs VHF vs flares vs SSB vs SatPhone, etc.

We seem to agree here on the board (Wow. Reread that and grin.) that the best chances for a vessel in trouble lay with having a GPS/EPIRB, registered, with updated contact information, and providing the shore-contact basic info (ie. # of souls aboard; last port / intended port of call). (Now reread that note above.)

If any or even all of that information is inaccurate or missing then SAR efforts will be delayed, BUT the SAR efforts will commence IF an EPIRB signal hits the system.

Old 121.5 MHz units are virtually useless. {Possible: somebody's search plane might still have the proper equipment to hand and could zone in on the signal. Not recommended to trust.} Best to remove batteries and dispose of unit.

Middle-Old combination 121.5 / 406 MHz units sans GPS would still notify SAR via the 406 part but search footprint would be very large.

Newer 406 MHz units sans GPS will notify SAR but search footprint would be very large.

New 406 MHz GPS units give the quickest response in the narrowest footprint.

If each crew person has a new version 406 MHz PLB with GPS - well, that's the Cat's Meow.

Does that about sum things up? Anyone have disagreement?

Right, then.... Suggested topic for a new thread: Buy a PLB with GPS for your boat dog? {One wonders how the on-scene SAR folk would react ....}

ALL of the new EPIRBs have the 121.5 homing signal. The reason for this is so the rescue asset can home in on the EPIRB when in a 100 mile rage or so which is well inside the footprint of even non GPS EPIRBs.

While the GPIRBs broadcast an immediate position for the quickest notification...the real time response of SAR assets isn't much different as by the time the SAR assets are airborne or underway...much of that hour or so delay that the non-GPS EPIRB needs to be located via Doppler/low orbit satellite is been used up. The system was designed around non-GPS EPIRBs and while I still recommend them...making sure you can survive long enough to be rescued is way more important than buying one over the other.

[svmariane]

Originally Posted by psneeld

ALL of the new EPIRBs have the 121.5 homing signal. The reason for this is so the rescue asset can home in on the EPIRB when in a 100 mile rage or so which is well inside the footprint of even non GPS EPIRBs.

I stand corrected. Good to know. Thank you.

[MarkJ]

Originally Posted by s/v Jedi

ORBCOMM has recently launched two dedicated AIS microsatellites, one in an equatorial orbit and the other in a polar orbit, which allows ORBCOMM to provide complete global AIS coverage. ORBCOMM will be launching 17 additional AIS-equipped next generation satellites beginning in late 2013.

"complete global AIS coverage".... Not quite. There are some difficulties picking up Class B because of the low wattage. But I dont know if thats confined to the coastal ports where there is normal electrical interfearence. Maybe off-shore will be easier to sneak that 2 watts of Class B power up to the satellite.

Its a damn good reason to keep those AIS cables, coax and connectors in shiny new condition. If it can get to the satellite we have a real secondry safety layer!

Mark

[goboatingnow]

[

Originally Posted by svmariane

]Regarding EPIRBs:


We seem to agree here on the board (Wow. Reread that and grin.) that the best chances for a vessel in trouble lay with having a GPS/EPIRB, registered, with updated contact information, and providing the shore-contact basic info (ie. # of souls aboard; last port / intended port of call). (Now reread that note above.)

No disagreement here

If any or even all of that information is inaccurate or missing then SAR efforts will be delayed, BUT the SAR efforts will commence IF an EPIRB signal hits the system.

Old 121.5 MHz units are virtually useless. {Possible: somebody's search plane might still have the proper equipment to hand and could zone in on the signal. Not recommended to trust.} Best to remove batteries and dispose of unit.

121mhz is no longer part of COSPAR SARSAT. Hence its not an Epirb

Middle-Old combination 121.5 / 406 MHz units sans GPS would still notify SAR via the 406 part but search footprint would be very large.

Newer 406 MHz units sans GPS will notify SAR but search footprint would be very large.

New 406 MHz GPS units give the quickest response in the narrowest footprint.

If each crew person has a new version 406 MHz PLB with GPS - well, that's the Cat's Meow.

Does that about sum things up? Anyone have disagreement?

There is no middle old combination of 406 MHz Epirb. The signal characteristics remain standardised , newer or older 406 mux units without GPS work the same and give a far far smaller footprint then the old 121 systems ( timing stabilisation is key to accuracy )

Non gps epirbs remain the mainstay of the system, the system supports them fully.

PLBs do not replace the need for a ships Epirb , PLB databases are not available everywhere only epirbs really are standardised across countries.

Dave

[psneeld]

Not sure the system knows the difference between a PLB and EPIRB...except by registration code...and in the USA it all goes into the same pile/system from what I've been told.

While EPIRBs have features that PLBs may not and vice versa...pick the one that best suits your survival plan(s)...

http://epirb.com/difference_between_EPIRBs_PLBs.php
The differences between EPIRBs and PLBs

Personal Location Beacons work in exactly the same way as EPIRBs by sending a coded message on the 406 MHz distress frequency which is relayed via the Cospas-Sarsat global satellite system.
However, there are a number of differences between them. PLBs are designed to be carried on the person so they are much smaller, some such as the Fast find are not much larger than the size of a mobile phone. PLBs are designed to be used anywhere in the world, on the sea and also on land. Some don't float but may come with an additional floatational sleeve which they should be carried in.
PLBs, once activated, will transmit for a minimum of 24 hours; while the battery life on an EPIRB is at least double (a minimum of 48 hours). An EPIRB is registered to a vessel, whereas a PLB is registered to a person. This means that if you are crewing a yacht and you swicth to a new yacht the plb is still correctly registered; however, if you have an EPIRB and buy a new yacht you will need to re-register it when installing in your new boat. EPIRB PLB

[goboatingnow]

Originally Posted by psneeld

Not sure the system knows the difference between a PLB and EPIRB...except by registration code...and in the USA it all goes into the same pile/system from what I've been told.

While EPIRBs have features that PLBs may not and vice versa...pick the one that best suits your survival plan(s)...

There are significant differences between PLBs , but not as you say at the satellite end. Registration databases do not exist in all maritime countries for PLBs , epirbs have to confirm to a specific feature set whereas PLBs can be anything

Its debatable what use a PLB is individually worn to a person lost over board , in my view personal AIS SARTs will replace PLBs for crew people with a whole Ship GPIRB remaining as a global distress system

Dave

[psneeld]

Based on PLB performance over the last few years...I have one and no EPIRB....granted I'm a near coastal and ICW guy...and I certainly recommend EPIRBs for the offshore guys.

PLBs are investigated just like EPIRBs as was stated before...the satellite or system doesn't know...just the watchstander and they will investigate whether the database is standardized or not...and like before...maybe it will take a little longer but if you are off your countries coast and PLBs are authorized for use there...I'd say you are OK as long as the PLB limitations (endurance, antenna and activation method) aren't liabilities.

[s/v Jedi]

Also plb for me. There is no difference on the rescue side when "your country" allows to register them. There is even a McMurdo with 48-hour battery now but it is bigger so I chose the Fastfind 220.

The disadvantage of a plb is with MOB situations, where a personal AIS transponder is better. Here too McMurdo is leader and we already saw cruisers carry them.

The wait is for a combo of these two.

[Wotname]

Just a data point.
Although EPIRBs have a minimum 48 hour battery capacity, the 406 transmitter switches itself off after 24 hours and the remaining battery life is used to power only the 121.5Mhz transmitter. The 121.5 MHz continues to transmit until the battery is fully exhausted.

[goboatingnow]

Originally Posted by Wotname

Just a data point.
Although EPIRBs have a minimum 48 hour battery capacity, the 406 transmitter switches itself off after 24 hours and the remaining battery life is used to power only the 121.5Mhz transmitter. The 121.5 MHz continues to transmit until the battery is fully exhausted.

I would like a reference to that.

COSPAR SARSAT specifications state the 406mhz beacon operating time is 24 hours minimum , but IMO GMDSS compliant beacons must be able to transmit the 406 MHz signal for a minimum of 48 hours

Dave

[Wotname]

Originally Posted by goboatingnow

I would like a reference to that.

COSPAR SARSAT specifications state the 406mhz beacon operating time is 24 hours minimum , but IMO GMDSS compliant beacons must be able to transmit the 406 MHz signal for a minimum of 48 hours

Dave

I am currently offshore and don't have access to any technical manuals but I will see what I can dig up when I get home (maybe a week).

I seem to remember I came across this a few years back in either an Artex or Kannard workshop service manual and I was somewhat surprised at the time. I understood that this was COSPAS SARSAT requirement but I could be wrong about it being a requirement.

It was all about having sufficient and stable voltage to maintain the integrity (stability) of the 406 frequency, especially at low temperatures.

[Wotname]

Or it might have been a conversation I had with a GME tech rep

[goboatingnow]

Originally Posted by Wotname

Or it might have been a conversation I had with a GME tech rep

I don't beleive its the case for IMO EPIRBs

[Mr B]

I was under the impression that 406 Epirbs in Australia must transmit a signal, Minimum 48 hours by law,

[Wotname]

Originally Posted by goboatingnow

I don't beleive its the case for IMO EPIRBs

When I return from off-shore, I will dig up my GME tech contact and get to the bottom of this

Originally Posted by Mr B

I was under the impression that 406 Epirbs in Australia must transmit a signal, Minimum 48 hours by law,

That is correct, it is just a question if the requirement applies to the 406 transmitter or just only to the 121.5 transmitter. The devil is always in the detail.