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Debris found came from missing Titan sub, says friend of passengers

bbc.com

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Re: Debris found came from missing Titan sub, says friend of passengers

#31

Post by can16358p »

fuzzbazz wrote: post #12
danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

Would the implosion have been loud enough? I mean the thing was a tiny 7x3m cylinder located 700Km from the nearest coast...

Sound can travel MUCH further and fast underwater, so in the event of an implosion, it might create enough of a spike in hydrophones that is statistically significant. Also the experts might be able to analyze the signal's signature to confirm (or bet) it's an implosion.

Crossmatch that with the time of loss of communication and it's safe to assume that it's it.

Re: Debris found came from missing Titan sub, says friend of passengers

#33

Post by can16358p »

quasse wrote: post #3
ClassicOrgin wrote: post #2

Based on this it seems pretty likely that it immediately imploded and the ‘banging’ was from the Titanic debris itself.

The banging was likely the sound of hundreds of news organizations flogging this story to get more clicks.

Nope; banging was officially announced in the press conference of the search and rescue team.

Though they could not confirm that it was really the sub (they probably thought that it was, but they can't officially say it).

Re: Debris found came from missing Titan sub, says friend of passengers

#34

Post by RajT88 »

danso wrote: post #9
ak_111 wrote: post #4

Earlier quoted context omitted.

Why is it more likely that it immediately imploded rather than after a few days? The latter is more probable to me as it has never been tested under water for more than a few hours at a stretch. This will also be consistent with your banging hypothesis which was only heard after a day or two when it got lost. And also with the fact that no immediate sound disturbance was registered with the controlling ship. I of cou…

There's little other explanation for why contact would be abruptly lost. The company said that the sub has multiple forms of ballast, including systems that could be activated manually, and ties that were designed to dissolve after 20+ hours in seawater, allowing the sub to rise even if the crew were unconscious. > The latter is more probable to me as it has never been tested under water for more than a few hours at…

> There's little other explanation for why contact would be abruptly lost.

You'd think - but past passengers have said that when they dove they lost contact as well.

Mutiple trip passengers said they lost contact every time.

So multiple anecdotes of loss of contact with the same vehicle without an implosion. The jankiness of this operation continues to be discovered bit by bit.

ETA:

https://abcnews.go.com/US/former-titanic-submersible-passeng...

Re: Debris found came from missing Titan sub, says friend of passengers

#35

Post by buggythebug »

danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

Ya but even so they could have sent rescue ships there because "we think it could be here" - nothing given up.

Re: Debris found came from missing Titan sub, says friend of passengers

#37

Post by buggythebug »

PartiallyTyped wrote: post #32
mrabcx wrote: post #26

Probably better to go away in an instant rather than sitting and waiting for the inevitable to happen.

Or succumbing to paranoia that others might murder you to survive themselves.

ya but if they murder someone, the victim will decompose - prob not good to breathe that stuff in.

Re: Debris found came from missing Titan sub, says friend of passengers

#39

Post by CoastalCoder »

buggythebug wrote: post #35
danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

Ya but even so they could have sent rescue ships there because "we think it could be here" - nothing given up.

I could imagine a cost-benefit analysis making sense here.

- Pro: increased chance of saving a few people's lives

- Con: risk of leaking info about U.S. sonar sensitivity

I.e., the decision would depend on the magnitude of the "pro" and "con" probabilities.

Re: Debris found came from missing Titan sub, says friend of passengers

#40

Post by margalabargala »

fuzzbazz wrote: post #12
danso wrote: post #6

I wonder if U.S. agencies (e.g. the Navy) had picked up the sound of the implosion days ago, back when the Titan was said to have lost communication, and knew all this time that the Titan had likely already been destroyed. But there's no incentive for them to publicly say anything, as it would hint to their underwater surveillance capabilities. And the "rescue effort" is good practice for their crews. I watched most…

Would the implosion have been loud enough? I mean the thing was a tiny 7x3m cylinder located 700Km from the nearest coast...

I have no idea specifically how loud it would have been. However with some probably-reasonable guesses, it looks like it actually would have been quite loud.

Here's a naval study where they measured underwater sound propagation: https://www.navymarinespeciesmonitoring.us/files/7514/2780/4...

They found that a 10lb block of C4 exploding produced ~210db of underwater sound. If we use that sound level as an approximation of the implosion of 200 cubic meters of submersible, which seems not completely unreasonable, then we can use the inverse square law to calculate the perceived sound far away.

Halifax, NS is 1100km from the Titanic wreck. A sound that is 210db at 1 meter, is 89db at 1100000 meters. Boston is 1700km away; at that distance it would be 85db.

85db is really quite loud. You would be able to hear that, if you were underwater and paying attention.

If the implosion was instead, say, 180db, then it would have been 55db in Boston harbor. Still easily detectable by instruments.

For reference, when divers are performing construction using e.g. rock drills, those commonly reach 170db. The implosion of close to 200 cubic meters of air seems like it would produce a louder noise than a rock drill.

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