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by richardjam73 1095 days ago
GPS is a one way system. A GPS receiver can only tell where it is, it does not transmit its position. To transmit position you would use a EPIRB. A EPIRB however cannot work underwater as its radio signal would be blocked by the water just as a GPS signal is blocked.

They are looking for this submersible by sonar. You don't need a nuclear submarine for sonar as it can done with ships ,sonobuoys dropped by aircraft or RV subs with sonar.

1 comments

These are all good answers by the way thank you. Isn't there like an "emergency transponder beacon" or something (like aircraft have?) that ships and submersibles must have? Why can't this be used?
That’s what the EPIRB is… problem is it has to reach the surface to broadcast; they’re designed for finding floating vessels / life boats, not submerged objects (in this case, tombs). To be useful it would need to be spooled out on a VERY long line that you could follow back down. In this case that means the EPIRB would need to be buoyant enough to float both itself and 4000+ meters of heavy line … which would be great, although also a threat to navigation.
Isn't there a way to use the charge conductivity of water to send a signal--like "electrolysis radio"? Alternately it seems a constellation of cheap radio beacons / high powered IR reflectors, that can float to the surface at a constant rate in event of emergency. So you basically end up with a 2D surface trail of reflectors laid over time since the incident. That should be somewhat helpful to pin down a search area, I would imagine, without relying on a single one, or having a long spool line. But I don't know for sure, just spitballing. Those poor people :(
People have been spitballing on this problem for generations, and that latter one’s been tried too… problem is it’s effectively the same thing as trying to pinpoint a diver by her bubbles; if she’s near the surface, works great… if she’s 4KM down then the bubbles hit the surface spread effectively randomly over hundreds and hundreds of square kilometers, and usually kilometers off horizontally.

The best way to maintain communication with a submersible is a tether. The best way to know the position of a submersible is a tether. The best way to raise a submersible in trouble is a tether… this company chose to go another way. And, let’s be clear, even if they knew precisely where it was the odds are very good that they couldn’t possibly effect a rescue.

The grim truth is that everyone aboard is already dead, the hope is that it was a sudden implosion rather than slowly freezing, drowning, or asphyxiating.

You were right man! Tragic. I'm hoping you're a navy insider and can feed us interesting tidbits about UFOs. Any stories? Do you know how the Navy detected the anomaly? Was a ship nearby or was it their monitoring grid? It's good they informed everyone--I had a feeling they definitely knew what happened or would be the ones who would find it.
Not Navy, just did some technical diving when I was younger. Most likely the signature of the implosion was picked up by the old fixed hydrophone arrays that form the backbone of submarine surveillance. It would have been like a really loud thunderclap as about 20 cubic meters of interior volume (and 5 people) tried to instantaneously squeeze into 0.05 cubic meters (about the space 2/3rds of 1 human usually occupies)… odds are hydrophones were still picking it up hours later and thousands of miles away.

And yeah, they knew pretty quick that a sound consistent with an implosion was heard at a time consistent with the loss of communication… not entirely sure why there wasn’t more communication of that earlier, though. Probably some fairly rich constituents pushing on the political side for a showy (and costly) rescue attempt that was always going to end up being a salvage and recovery operation.

Now that the engineering choices have become clear it’s no wonder this happened… they really had “disrupted” their way into a time bomb.