Nautilus Lifeline - why no satellite communication?

[Akimbo]

Even if you do drift more than the 8 miles, I would think your boat would be traveling with the current to find you or at least doing large circles and you would eventually come into range.

Maybe you've never been the captain of a dive boat that has lost a diver at sea. Maybe you don't know that it's the worst feeling in the world, not knowing whether to conduct a surface search for a victim, or a bottom search for a body. Maybe you haven't spent 5 days searching for a body that may or may not exist, 2 days after the Coast Guard called off the search. Maybe if the victim had a PLB, we'd have known if they were alive or not.

I believe the point is that with a VHF radio with DSC (which transmits your GPS coordinates), it is far more likely that your dive boat will come within range when searching long before it is a body recovery job. The disadvantage is activating a PLB or EPIRB starts a full blow air-sea rescue operation by the Coast Guard and all boats in range of your coordinates. In most cases, using the PLC costs anywhere from 50-$150 to get it put back together at the factory.

Unless you are decompressing off a buoy for an hour, you are not likely to surface more than a mile from the boat. Like I wrote above, there are conditions where a PLB make sense. In the most extreme conditions I see the sequence being inflate SMB, no response —> try the VHF for an hour or so —> Light off the PLB, and strobe light if it is at night and you have one.

You have to consider where you are diving. You can forget all three in an Arkansas quarry, carry all three when diving the Doria or Lusitania. They all have limitations. Should we carry three PBS as backup for fail-safe redundancy? I don’t mean to make lite of your comments because it is damn serious. Like everything in life, it is about the compromise between risk, probability, cost, and appropriate response.

As a dive boat captain, how long before you ban PLBs after a few rookie divers set theirs off a quarter mile from the boat because you didn’t pull anchor and pick them up fast enough? It would be pretty nice for you to be able to say "are you OK and hang on until I can recover everybody" or maybe “swim your ass back you lazy SOB”. I suspect that the Coast Guard would have a few words with you after maybe twice.

 

[Wookie]

I disagree, mostly because I spoke with the Coast Guard before spending thousands of dollars to outfit my divers with PLB's. One of the things about a PLB is that the Coast Guard ALWAYS calls the emergency number when one goes off before they move any resources. Additionally, I can call the local SAR center and get coordinates for the missing diver before the CG moves any assets. I can (haven't yet, but plan to) buy a RDF receiver that will tune into the 121.5 transmitter in the PLB and go find the missing diver.

The Key West Coast Guard, BTW, was very supportive of me being proactive and buying the PLB's. My insurance company was ecstatic. They went through the missing diver issue with me.

 

[fjpatrum]

I think that it is very unlikely to find yourself outside of the 8 mile range under most diving circumstances. 8 miles is a very long way on the open ocean especially for most dive boats being smaller and traveling slow IOT provide better comfort for the more weary divers.

Also the EPIRB is not a small device. Adding such capabilities to a device meant to be small and portable in the off chance that someone has a 1:100,000,000 chance of being out of the 8 mile range would probably make it less marketable to people looking for a small device more than it would be for someone looking for the EPIRB type system.

Not to discount what you're saying, but there is no size reason not to add an EPIRB.
ACR Products
This is just one example that isn't much larger than the Nautilus. Adding the capabilities of one to the other would be minimal, size wise. The issue is more a cost issue than anything else, and like you said, the likelihood of needing the capability is astronomically low compared to the other functions already provided.

EDIT: After looking at this a bit more, this is a PLB rather than a true EPIRB so you may be correct in your size assessment. Sorry.

 

[Akimbo]

I disagree, mostly because I spoke with the Coast Guard before spending thousands of dollars to outfit my divers with PLB's. One of the things about a PLB is that the Coast Guard ALWAYS calls the emergency number when one goes off before they move any resources. Additionally, I can call the local SAR center and get coordinates for the missing diver before the CG moves any assets. I can (haven't yet, but plan to) buy a RDF receiver that will tune into the 121.5 transmitter in the PLB and go find the missing diver.

The Key West Coast Guard, BTW, was very supportive of me being proactive and buying the PLB's. My insurance company was ecstatic. They went through the missing diver issue with me.

In your case where the PLBs belong to the boat, I totally agree. For those who don’t know, PLBs are registered with NOAA/SARSAT. SARSAT calls contact numbers you register when they get a signal — maybe Capt Wasson can explain even more.

For personally owned PLBs, SARSAT can’t just radio your charter boat unless you notified them which boat you were on. Keep in mind they work onshore as well so carry it hiking in the wilderness or even skiing. All too often, they have to figure out who to call... as you are drifting away. Having a 121.5 MHz RDF onboard is even better.

Question Captian: Which PLB are you using, how big a deal is it to train divers to use it, and what does it cost to restore it after using it?

I gotta commend you big-time for your setup and I think the service should be splashed all over your Web page, well done. You get my business if I come to Florida.

 

[Wookie]

You are correct. A PLB that is registered to a person is about as useful as a MOB transmitter, except if your contact really knows where you are. My PLB's are McMurdo 210's, because they are the smallest available. They are in a Light Monkey canister along with a whistle, dye pack, cyalume stick, energy bar, and whistle. I haven't yet found a source for drinking water or 5 packs of smokes.

I just got them set up yesterday, so I haven't had anyone set one off. I don't know how much to re-set it.

 

[Akimbo]

… They are in a Light Monkey canister along with a whistle, dye pack, cyalume stick, energy bar, and whistle. I haven't yet found a source for drinking water or 5 packs of smokes…

Wow, feeding them while they are lost at sea sets a new standard! Seriously, good ideas.

I use the FastFind 210 as well. I am not sure what the Light Monkey canister costs but they also fit perfectly in the OMS (which I first learned from a Scubaboard post).

General Heads-Up Warning (not sure if it applies to Light Monkey): One issue with canisters that secure the lid with Nielsen snaps is that expanding air will escape past the lid seal just like a relief valve. You could end up with a pressure-seated seal that is hard to break when the temperature and/or barometric pressure changes… like when you close the canister in hot weather and cold water drops pressure inside the housing. You also want to take the lid off or remove the O-ring before taking it on an airplane unless there is an equalizing valve. A screw-on cap with piston O-ring provides enough mechanical advantage that you can “probably” break the seal with cold wet slippery hands.

One nice thing about the 210 is the built-in a strobe. I can’t remember exactly, but it seems like getting the FastFind refurbished after deployment was more than $100; which is irrelevant if you actually need it. However it makes me think twice before breaking that seal.

 

[Wookie]

When I went back to read your (Akimbo's) post at the top of the page I realized something I hadn't explained. We lost a diver in 2001. We searched on the surface along with 20 other vessels, Coast Guard helo and Falcon jet, as well as floating assets. We also searched the bottom in 185 feet of water. If he had had an EPIRB/PLB/Lifeline, we'd have had a better idea if he was floating or on the bottom. Since that time we have started doing far more extreme diving, including Gulf Stream diving and deep deep wrecks with long deco obligations. Sometimes divers end up many miles from the entry point. My longest string of divers was 6 miles and I was moving back and forth along that 6 mile line of lift bags watching for divers to surface. During that time, I had the wrong number of liftbags/SMB's, and didn't know if I was missing anyone or not. I wasn't, we had a reel failure, so one diver was not on a SMB (and was on a rebreather) and other teams had each popped a bag. It's a pretty helpless feeling. With a Nautilus/PLB/EPIRB, at least I'd know where to start looking, on the bottom or the surface. I would assume a diver with a PLB would set it off if they made the surface. I know, never assume, but you have to start somewhere.

 

[jbtut]

I'm not familiar with the Nautilus Lifeline enough to know if this is a plausible option or could be added, but here's a suggestion: Add a wire to a SMB that, when inflated could be connected to your lifeline as an extended range antenna. I'm not entirely familiar with radio transmission antenna design, although I'd imagine a flexible unit could be built either as a ribbon or wire that would withstand the flexing of a SMB being rolled up and optimized for the wavelength of transmission.

If the constant rolling up is too hard, you could even go super low tech and just fill up your SMB, turn it upside down and hook the lifeline into your velcro SMB ties and hold it up in the air to transmit your location.

I'm just brain storming here, but I'm thinking this might help solve a transmission range issue if there is one from being too low in the water.

 

[Akimbo]

... We lost a diver in 2001. We searched on the surface along with 20 other vessels, Coast Guard helo and Falcon jet, as well as floating assets. We also searched the bottom in 185 feet of water. If he had had an EPIRB/PLB/Lifeline, we'd have had a better idea if he was floating or on the bottom...

Thanks for that. It helps a lot for divers to see the Captain’s perspective. The conditions you work in certainly makes a PLB the best choice IMHO — far offshore, not necessarily close to other boats, and in a fast current like the Gulf Stream. I will use the Nautilus in places like Northern California where you are usually closer to shore (the continental shelf drops off fast compared to the east coast and gulf). Currents usually aren’t that swift and there are usually other boats within a few miles. Maybe someday we will have satellite phone build into PLB… or both built into decompression computers!