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

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hope there is a viable rescue operation near you.

I think this thought and a sense of realism is key !

In many of the locations in Asia, Maldives & Africa, the dive boats will have a marine radio. I have been on boats which have no compass or other navigation equipment, but the navigation skills of the crew were impressive. A DSMB and a horn, maybe a mirror, has to be the primary means of attracting attention in these locations. Unless you are in the first world or on a liveaboard with fancy navigation systems, PLBs and MRGs are wishful thinking. I can assure you that large commercial vessels which do have the fancy equipment are not interested and are not going to divert from their course …

I have been on sailing vessels crossing shipping channels trying to avoid collisions, and tried to contact large commercial vessels on marine radio, having identified them by name via AIS, and they just ignore you.

Good luck … the manufacturers of PLBs and MRGs want you to believe that vessels will respond. My own view is that Lifeboat organisations (if there is one), Coastguards (same), western operated leisure craft (liveaboards and yachties) in the vicinity are most likely to respond. These are thin on the sea outside the first world. Local craft don't have the fancy equipment. Large commercial craft are not interested.
 
I was certified 30 years ago and for a decade only ever carried a torch and whistle. I do, however, recall that about the time that I was certified, there was a boat seperation incident in Palau. I recall that the divers were found with arms linked to form a circle. Sadly, they had passed on when they were found. One of the divers had a slate and had written the message, "We can see you searching for us, but you cant see us." See When divers go missing

Then I stopped diving for 20 years before resuming in April last year. Since resuming, I've done a number of trips with about 200 dives in total and have met at least 3 divers who had experienced boat seperation. I say at least 3 because that is what I said in an earlier post. The reason for this is that at the time I made my earlier post, I vaguely remembered a 4th but could not retrieve the memory of who it was. I have since recalled that the 4th diver was my tec (extended range nitrox) instructor who had mentioned that he was once left behind by a dive boat. He did not carry a MRG or PLB but he had a great big 10' sausage. Therefore in 12 months, I have met 4 divers who had experienced boat seperation, three of whom were certified to instructor level. I do not know of any statistics for boat seperation but, to me, I have met 4 divers too many who have experienced it.

Realism is good. This includes understanding that boat seperation does occur. Whether vessles will respond to your signalling equipment is not within your control. Realism also includes the understanding that carrying signalling equipment will never decrease your chances of rescue in event of boat seperation. What is within your control is making a conscious and well informed decision about what signalling equipment you wish carry.
 
Dogbowl is correct. A PLB sends your location to a satellite, which then becomes part of a Search and Rescue operation, if one is available for your location. The Nautilus MRG sends your location to a ship-board radio, which can then find you, if it is close enough to hear you. The range of the PLB is all the way to the satellite. The range of the MRG is pretty much line-of-sight, not more than a mile or two, usually. They both try and save you, but using very different technologies with different values for your specific location and situation. Having both is optimum: you first go for the short-range, direct action of the MRG, and failing that go for the satellite with your PLB and hope there is a viable rescue operation near you.

That’s why I list my signaling devices according to the following 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
 
I was certified 30 years ago and for a decade only ever carried a torch and whistle. I do, however, recall that about the time that I was certified, there was a boat seperation incident in Palau. I recall that the divers were found with arms linked to form a circle. Sadly, they had passed on when they were found. One of the divers had a slate and had written the message, "We can see you searching for us, but you cant see us." See When divers go missing

Then I stopped diving for 20 years before resuming in April last year. Since resuming, I've done a number of trips with about 200 dives in total and have met at least 3 divers who had experienced boat seperation. I say at least 3 because that is what I said in an earlier post. The reason for this is that at the time I made my earlier post, I vaguely remembered a 4th but could not retrieve the memory of who it was. I have since recalled that the 4th diver was my tec (extended range nitrox) instructor who had mentioned that he was once left behind by a dive boat. He did not carry a MRG or PLB but he had a great big 10' sausage. Therefore in 12 months, I have met 4 divers who had experienced boat seperation, three of whom were certified to instructor level. I do not know of any statistics for boat seperation but, to me, I have met 4 divers too many who have experienced it.

Realism is good. This includes understanding that boat seperation does occur. Whether vessles will respond to your signalling equipment is not within your control. Realism also includes the understanding that carrying signalling equipment will never decrease your chances of rescue in event of boat seperation. What is within your control is making a conscious and well informed decision about what signalling equipment you wish carry.

The diving accident that got me started to assemble my signaling devices is 4 diveres went missing - Malpelo, Colombia It is a very sad diving accident that all ocean divers ought to read.

Had the DM alerted the liveaboard about where they were, the lost of 2 divers, including the DM himself, would have been avoided. They (4 divers + DM) saw the liveaboard in the distance, but the liveaboard couldn’t see them.

One of the diver decided to remove his gear and swam towards the liveaboard, but after seeing the boat sailed away to the wrong direction, he changed direction & swam to Malpelo island & hang on for dear life on the rocks for the night. The next morning another liveaboard found & rescued him.

Full Search & Rescue mission for the rest of the divers was done afterwards. 2 divers found floating with their SMB & rescued. DM was never found. The fourth diver’s body parts was found.
 
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That’s why I list my signaling devices according to the following order of importance:
1. 6’ DSMB with 100’ line in spool Minimum! 8 or 10 ft is better.
2. Dive Alert Requires tank, and air in tank. Have a whistle too.
3. Signal Mirror Time of day and WX dependent
4. Nautilus Marine Rescue GPS Value depends on the equipment and willingness of the boats nearby.
5. PLB1 Value depends on the SAR capabilities and interest of national and local authorities.
6. Dive light Night only.
7. Strobe Night only.
8. Glow stick with 6’ string Night only.
9. Leash with carabiners. Often called a buddy line.
Notes are embedded in Red above. Some of the things are obvious, but need to be said.
Missing but also valuable are light/smoke flares and colored dye.
Mk8 distress signaling flare - Day / Night
Divesoft Fluorescein Marker Dye
 
Notes are embedded in Red above. Some of the things are obvious, but need to be said.
Missing but also valuable are light/smoke flares and colored dye.
Mk8 distress signaling flare - Day / Night
Divesoft Fluorescein Marker Dye

Thanks!

I pretty much max up on the space I have in my BCD pockets, like to streamline my dive gear & try not to hang stuff like Christmas tree ornaments that would add risk of entanglement when diving in confined / overheard environment. So, I had to pick the best & compact signaling devices that fit into the pockets and had to take the flare & dye off the list.

As far as whistle, I have it strapped to my DSMB (you might see it (in orange color) in the picture I attached in post #1).
 
I think this thought and a sense of realism is key !

In many of the locations in Asia, Maldives & Africa, the dive boats will have a marine radio. I have been on boats which have no compass or other navigation equipment, but the navigation skills of the crew were impressive. A DSMB and a horn, maybe a mirror, has to be the primary means of attracting attention in these locations. Unless you are in the first world or on a liveaboard with fancy navigation systems, PLBs and MRGs are wishful thinking. I can assure you that large commercial vessels which do have the fancy equipment are not interested and are not going to divert from their course …

I have been on sailing vessels crossing shipping channels trying to avoid collisions, and tried to contact large commercial vessels on marine radio, having identified them by name via AIS, and they just ignore you.

Good luck … the manufacturers of PLBs and MRGs want you to believe that vessels will respond. My own view is that Lifeboat organisations (if there is one), Coastguards (same), western operated leisure craft (liveaboards and yachties) in the vicinity are most likely to respond. These are thin on the sea outside the first world. Local craft don't have the fancy equipment. Large commercial craft are not interested.
Outside the main commercial shipping lanes at remote third world divesites, and beyond marine VHF radio/VHF rescue beacon broadcast range (like the Nautilus MRG), an activated and in-distress PLB to satellite detection is the only way remaining of obtaining a GPS position fix that uniquely identifies YOU as the registered owner.

If pre-planned smartly with designated Emergency Contacts having your full flight/boat/dive-op & travel itinerary info to provide to a Rescue Coordination Center, PLB's are the last resort and last best chance of being rescued in a lost at sea scenario:
  • In June 2010, 16-year-old Abby Sunderland attempted to break the record for being the youngest person ever to complete a solo sail around the world. But when she found herself stranded at sea after a storm damaged her boat, Abby's life was saved by a NASA-developed Personal Locator Beacon (PLB), which transmitted a distress signal to a Search and Rescue (SARSAT) satellite, 22,500 miles away in space. On October 25, 2010, Abby visited NASA's Goddard Space Flight Center to meet the team that developed this Search and Rescue technology more than 30 years ago.
Abby Sunderland - Wikipedia
Rescue of Youngest Solo Sailor to Attempt Non-Stop Circumnavigation

  • Signal of plb will go through in indonesia. Rescue time depend on the location of the military. Case : I went diving in manado area with my plb1 in a plastic waterproof flexible case. Upon surfacing, 15 min later i realized the plb was activated accidentally (due to pressure at depth). Since the antenna of the plb was not deployed and it was only less then 30 min of accidental activation? I did not think much of it (i thought for sure signal would not have gone through as antenna was not deployed and not much time was activated and went on our 2nd dive) (Activation was near resort dive site). Upon return to land -We saw indonesian military personel at the resort (we thought it was routine inspection for that area). That was maybe less then 2 hour after discovery of the accidental activation. (Manado military have to take boat from mainland to resort island. 20 min away from mainlaind). Later when we turn on our cell phone (cell phone reception signal only on land near resort) we we shocked to get many missed call, texts, and emails from our family emmergency contact. The message was : jakarta sar detected an activation of your plb near manado. North american Sar Contacted emmergency contact and verify situation. Family Emergency contact said we were diving in indonesia and cannot reach us. North american SAR told our emergency contact that jakarta said military was notified!! That was when we panicked and realized that the plb1 is so powerful that even with the antenna down, and short activation time, the plb satellite signal actually went through! We frantically called NA sar and notified of the accidental activation. (Our family was panicking as they thought something happened to us). After that trip we bought a proper hard case dive canister for the plb.
Canadian diver and buddy rescued near Apo Island, Philippines
 
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More "realism":

Other than the contingency of drifting away on the surface, downcurrent of the Diveboat unseen. . .

This is another example of a common scenario that will test the experience of your skiff driver to find and pick you up before deteriorating into a worst case lost-at-sea situation; Surfacing post-drift dive into a momentary tropical rain squall in near zero visibility:
(Puerto Galera Bangka Driver luckily found us 30 minutes later; In conditions identical to the above was the only other time I came close deploying the life raft and activating the PLB)

Given VHF rain fade and signal range degradation, it may be some time after the squall passes before a AIS/DSC VHF receiver picks up your Nautilus beacon again and homes in on you. In the meantime, all you can do is deploy a dive alert whistle, strobe and primary dive light & SMB; and as back-up last resort a properly registered PLB.
 
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In case anyone is interested, baSARnas, the Indonesian SAR organisation has 34 offices (kantor) and 65 posts (pos) according to Indonesian wikipedia.You can see the location of the offices and posts in the section titled ‘struktor organisasi’. See
Badan Nasional Pencarian dan Pertolongan - Wikipedia bahasa Indonesia, ensiklopedia bebas

Here is the English version. :)
National Search and Rescue Agency - Wikipedia

FYI, it’s no longer called BaSARnas, it’s now BNPP:
Sesuai Usulan Megawati, Jokowi Ganti Nama Basarnas Jadi BNPP - Kompas.com
 
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