Debris field found in search for missing submersible

Re:Debris field found in search for missing submersible by flir on Thursday June 22, 2023 @05:14PM (#36439106)

Yes, and as far as I can tell it's not even certain that what was picked up from the San Juan was an implosion. But on the other hand, the Polar Prince was sitting right on top of the Titan listening for pings, and apparently it didn't hear anything.

I'm not suggesting anything nefarious, I'm just hoping someone who understands these things better than I do comes along.

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Re:Debris field found in search for missing submersible by krisoft on Thursday June 22, 2023 @06:23PM (#36439981)

Sound can bend in the ocean in weird ways.

The ocean is not a homogenous mass. As you go down you can measure temperature, pressure and salinity changes. These all individually and together affect the speed of sound in the water. Given the right circumstances a layer can form which bends the sound waves away from an observer. It is possible that they couldn’t hear the implosion precisely because they were on top of them. Perhaps they could have heard the implosion better if they were off to the side a few kilometers, or if they would have had a hydrophone dangling to the other side of the layer. More info on the layer. [1]

This perhaps also can explain why they routinely lost contact with the sub during dives. (And normalisation of deviance explains how they become okay with that. [2])

1: https://oceanexplorer.noaa.gov/explorations/sound01/backgrou...

2: https://en.m.wikipedia.org/wiki/Normalization_of_deviance

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Re:Debris field found in search for missing submersible by masfuerte on Thursday June 22, 2023 @07:40PM (#36440765)

I'm speculating, but their ping detector may have had a filter for the frequency they were interested in. A low frequency explosion could easily have been ignored.

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