Best signaling devices from the searcher’s point of view - update

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I suspect the writer is still confused about the difference between the new Nautilus Lifeline (MRG) and PLB. I have contacted The Undersea Hunter operation about it. They are referring to MRG, not the older generation Nautilus Lifeline with 2 way radio, which is only capable to send DSC alert signal.

The MRG can send out both DSC and the more recent Automatic Identification System (AIS) signalling functionally, which includes your GPS coordinates and a Maritime Identification Digits (MID) user number, that comes in pre-programmed at the factory. The MID is unique to each MRG (e.g., mine is 972-69-6005, where 972 refers to Man Over Board code and 6005 is part of the serial number of my MRG). So, by pressing the red button, Argo AIS screen will display my MID, GPS location, and its distress alert alarm would sound.

When they issue MRG to each diver, each diver’s name would be linked to the MRG’s MID. So when a diver press the red button, Argo will immediately know who is lost at sea, assuming the 1 watt VHF signal with antenna rising 2 feet above the water is strong enough to reach the boat AIS.

Yes, but all that relates to the MRG only. Where is the PLB involved? What does Undersea Hunter mean by "PLBs ... paired with our [MRGs?]"
 
Yes, but all that relates to the MRG only. Where is the PLB involved? What does Undersea Hunter mean by "PLBs ... paired with our [MRGs?]"

That’s not quite what he said. He said (as shown in bold letters):
“Like any other electronic device that communicates with another system, it should be set up or registered with another available device -- in our case, a computable GPS-ready VHF radio. We equip each of our divers with one of our PLBs, which is numbered and paired with our computable VHF radio units. When a diver fires his unit, it will alert several monitoring posts. An identification number will appear that allows us to head the nearest boat directly to a specific person. We practice it regularly and usually reach the test PLB within 20 minutes from the time it was initiated."

I’m guessing that he’s pairing each MRG with his VHF radios since by pressing the MRG red button, it would broadcast SOS immediately & simultaneously via DSC every 4 minutes & AIS once per minute, according to Ryan Sawatsky of Nautilus Lifeline tech support, as I posted here:Nautilus Lifeline Radio So, Undersea Hunter try to utilize both alert signals (DSC & AIS) as redundancy. I’m also guessing that they used to have the older generation Nautilus Lifeline units that send DSC to their VHF radios.

I plan to contact Undersea Hunter customer support again to clarify this confusion.
 
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I haven't read the article, but from the quote, it seems the article is always referring to the MRG, but they're using "PLB" as a generic term, "Personal Locator Beacon", as in it's personal (single diver), a locator (GPS), and a beacon. It's an unfortunate misuse of "PLB" since PLB refers to a wholely different type of device.
 
I think there is also confusion here on on using the term "VHF." This should refer to any radio using a certain band of frequencies, namely 30-300 MHz. The term is sometimes used as shorthand for a marine VHF radio, which uses the frequencies from (about) 156-174 MHz. The radios may be for voice or digital transmissions. Specifically, one should say "VHF maritime mobile band" to conform to international descriptions. So, this means that both the Gen 1 and the Gen 2 Nautilus units are "VHF radios," because both transmit in those frequency bands. But only the Gen 1 (older) version has voice capability, so only it is a "VHF marine radio" as loosely described.
 
Now I’m more confused :(

Lisa Povedano of Undersea Hunter Group sent me this: Dive Program - Safety

In that webpage, it’s clearly shown a picture of the older generation of Nautilus Lifelines in docking station.

Anyway I sent her another email to clarify what PLB model that they use and “paired” with their VHF radios as described in the Undercurrent article.
 
Their statement "one of our PLBs ... paired with ... ['another device' that is] a computable GPS-ready VHF radio" is totally confusing. Surely the "computable GPS-ready VHF radio" refers to the current-generation Nautilus. If so, what is the PLB, and what do they mean by "paired with"?
 
After reading several divers lost at sea, I started to consider carrying several signaling devices, especially from the searcher’s point of view. I found this great old thread, Best signalling equipment from the searchers point of view However, the thread is over 10 years old when it was initially posted by Navy OnStar, whom is no longer active in SB. I figure, it is time to update the list & share what I carry for ocean diving.

Portability (small & light) of the devices is an important form factor since I would mostly travel by air to the dive sites. Also I like to streamline my rig. So, those devices need to be small enough to fit in my BCD pockets, instead of hanging around my BCD, like those ornaments on Christmas tree, which increase the risk of entanglement when diving through narrow passages or overheads.

Based on those requirements, I came up with the following signaling devices, by the order of importance:
1. 6’ DSMB with 100’ line in spool
2. Dive Alert
3. Signal Mirror
4. Nautilus Marine Rescue GPS
5. PLB1
6. Dive light
7. Strobe
8. Glow stick with 6’ string
9. Leash with carabiners

View attachment 449937

Except for the Dive Alert, they are all fit in my BCD pockets.

1. 6’ DSMB with 100’ string in spool
I think this is still the most important signaling device that all ocean diver should carry. I pick this closed bottom, nozzle inflated, 6” W x 6’ L DSMB for stiffness when it is fully inflated.

View attachment 449924

I want it to stick out like a sore thumb 6’ above the surface to insure good visibility during high seas. As the night creeping in, the DSMB is stiff enough to strap a small strobe on top of it.

The 100’ line spool is for launching the DSMB from depth to alert the boat crew early. Sometimes swift current may carry us into the blue water too far away from the boat crew to see by the time we surface.

2. Dive Alert
DiveAlert by Ideations
This air horn is very loud. The new version has lock to prevent false alarm. It also works underwater to alert my dive buddy when we get separated with poor visibility.

View attachment 449925

Since it is sandwiched between the LP hose & the BCD power inflator, it takes not much space on the BCD and no additional dangling thing.

3. Signal Mirror
It is very light & small. When the sun is bright, this device is very useful for reflecting the sun light to the searcher.

View attachment 449926

4. Nautilus Marine Rescue GPS (MRG)
Nautilus Marine Rescue GPS: Official Website
Most of my ocean dive trips are on liveaboards. Some of the liveaboards (Argo, Palau Aggressor II, Maldives Aggressor II, Nautilus Under Sea, Spoil Sport, etc.) are now provide MRG to their guests to carry during the trip at free of charge. If they do that, then I’ll leave my MRG at home. For the liveaboards that don’t, then, it is good to discuss diver lost at sea scenario with the boat captain & crew, show them my MRG, and load the boat MMSI into the MRG, so they will monitor their DSC /AIS for signal from my MRG in the event I were lost at sea.

View attachment 449929

5. PLB1
PLB1 - Ocean Signal
This is my last resort signaling device after receiving no visible response for a couple hours from the MRG. Once no boat visible in the horizon, then I’ll launch this PLB1.

View attachment 449930 View attachment 449931

If a liveaboard issues her own PLB to her guests, like Ferox would, Malpelo - Ferox new Colombian liveaboard then I’ll leave my PLB1 in the boat & carry her McMurdo S10.

6. Dive Light
Pretty obvious what this one is for.

View attachment 449932

7. Strobe
As dark set in, I plan to strap this small TekTite Mark-Lite LED Strobe Light on top of the DSMB, as shown below.

View attachment 449921
View attachment 449922

8. Glow stick with 6’ string
As mentioned in the old thread, this glow stick is for alerting any search plane / boat at night. By bending the glow stick to light it up, tying it to a string & swirling around overhead, such signal would be clearly seen by the searcher with night vision.

9. Leash with carabiners
As mentioned in the old thread, the idea here is to tie everyone together as a group so we would be easier to be spotted from the distance. Also we have greater survivability in group than alone, as mentioned in these lost at sea incidents:
Missing Divers - Komodo National Park
7 divers missing off Indonesian island

What other signaling devices do you all carry nowadays?

Very nice list!

We provide to our client a Personal Locator Beacon McMurdon s10 Smartfind S10

It is an innovative manually activated personal safety device which incorporates both AIS (Automatic Identification System) and GPS technology.

When activated the Smartfind S10 transmits a unique alert signal to the vessel the individual has come from and to all AIS enabled equipment within a typical 4 mile range, signalling that help is required in a man overboard or lost diver situation.


upload_2018-4-4_15-21-35.png
 
So is the McMurdo SmartFind in direct competition with the Nautilus Marine Rescue GPS? The McMurdo SmartFind looks more compact, which would be nice.

Thankfully, I see on McMurdo's website that they do NOT confusingly refer to the SmartFind as a "PLB." I'm familiar with McMurdo's FastFind line of PLBs.
 
Very nice list!

We provide to our client a Personal Locator Beacon McMurdon s10 Smartfind S10

It is an innovative manually activated personal safety device which incorporates both AIS (Automatic Identification System) and GPS technology.

When activated the Smartfind S10 transmits a unique alert signal to the vessel the individual has come from and to all AIS enabled equipment within a typical 4 mile range, signalling that help is required in a man overboard or lost diver situation.


View attachment 453669

Thanks! I hope I won’t need to use any of them. :)

I’m confused again. Doesn’t Personal Locator Beacon (PLB) transmit 406 MHz alert signal to LEOSAR & GEOSAR? I don’t see Smartfind S10 is doing that. It only transmit VHF to AIS. That’s why McMurdo says Personal AIS Beacon, NOT PLB. To me S10 is just a different form factor of MRG.
 
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https://www.shearwater.com/products/peregrine/

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