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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

#41

RIP to these guys, yes it was a risky trip. But it was into international waters and they were AFAIC explorers. Stuff like this can not be done without risk. Hopefully future subs will have more safety features.

This wasn't boldly going where nobody has gone before. Getting that deep safely has been a solved problem for decades.

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

#42
post #9
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…

> That's not true, they've successfully reached the Titanic several times over a dozen or so expeditions.

This is more concerning, given that metal fatigue is an understood phenomenon (1).

(1) https://www.faa.gov/lessons_learned/transport_airplane/accid...

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

#43

RIP to these guys, yes it was a risky trip. But it was into international waters and they were AFAIC explorers. Stuff like this can not be done without risk. Hopefully future subs will have more safety features.

This wasn't boldly going where nobody has gone before. Getting that deep safely has been a solved problem for decades.

I agree but not at 250k a head.

It should be safer, but everything is done to a price point and I'm sure those on board recognised the risk of such an expedition.

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

#44

Earlier quoted context omitted.

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.

Indeed, and moreover, the ability to detect underwater sound is probably aided by the lack of localized turbulence (wind noise in microphones) and the degree of sophistication sought after by navies due to the detection and counter-detection of military submarines.

Without any actual knowledge, I imagine that a ship or sub could be festooned with hydrophones, enabling it to detect faint noises, but also to determine their direction from phase information.

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

#45
post #19

Earlier quoted context omitted.

It's not a complicated or even malicious "coverup". They hear an anomalous sound, but don't know with 100% certainty that it's came from the lost sub. What is the Coast Guard supposed to do, not do anything the past few days and say it's because "Sorry we heard a loud sound at that time and are 99% sure that those people are dead"?

I must be missing something it seems simpler to assume "Coast guard gets report of lost sub and searches for a while". Why would you turn that into "USN knows that a sub imploded. Did nothing observable. Coast guard gets report of lost sub and searches for a while." I looked at the link, I can't see any reason to interject into that more capability than was demonstrated. It may exist, it may not. There is no reason t…

My assumption is that hearing this kind of long distance noise is well within the laws of physics and what we know of the U.S.'s capability. So I don't see this as "additional capability", but rather, am asking from a mindset of "How did they not hear a suspicious sound at the time of the missing sub?"

Whether they did or not, nothing would presumably change about the Coast Guard conducting search-and-rescue/recovery operations (since they still don't know for sure what happened). Worth pointing out that private explorers, led by Richard Garriott (aka Lord British, apparently), complained that they had optimal rescue equipment but got pushback from the U.S. officials:

https://archive.is/HXtFn

> “Magellan has received mixed signals, first hearing from US Gov to get ready, waiting for plans, then getting told to stand down,” Garriott wrote in an email sent to Vice Admiral William Galanis, commander of Naval Sea Systems Command, U.S. Coast Guard Rear Admiral John W. Mauger, who is leading the recovery mission, Congressman Lloyd Doggett, and Representative Eric Swalwell on Wednesday afternoon.

Again, hard to know if this is just standard operating procedure or not. If it's the case the U.S. govt already had things figured out by now, then it makes sense they weren't going to expedite Garriot's group, given that the search effort had already resulted in the loss of 1 (maybe 2) search vehicles:

> In addition, at least one ROV, possibly two, was damaged or destroyed during the search-and-rescue mission—a testament to the difficult conditions currently facing rescuers.

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

#46
post #25

Earlier quoted context omitted.

> 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. is there more information on these dissolvable ties? or their redundant ballast systems?

From David Pogue's report on his trip in 2022: https://unsungscience.com/news/back-to-titanic-part-1/ Excerpt from the transcript: But what if the hydraulic system breaks? Well, then they have roll weights. KYLE: Ah, so, we’ve got these weights here on the side, these are roll weights, we can actually roll the sub and those come off, and that gains us some buoyancy to come back to the surface. These are pipes that si…

thank you, couldn't find the right part of the interview

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

#47
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...

Navy sonar equipment can hear so much more than you would ever expect. Sound travels very well in water. The navy has software that pretty much tunes all of that out, similar to how radar ignores things under certain speeds as it's just not interesting to them. However, if they want, they can see/hear the raw data. There's all sorts of Navy stories about what can be heard, and not all of them are untrue.

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

#48
post #34
post #9

Earlier quoted context omitted.

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-t…

I listened to Reiss's (the passenger cited in that story) account on his podcast [0], and it's somewhat ambiguous. There are periods of spotty communication and long periods of the sub just getting lost. But not comms system/transponder abruptly going out and not being heard from again.

David Pogue seems to concur with this [1]. He saw them lose track of where the sub was located (wrt to the Titanic wreck), but he said the support ship never lost the ability to communicate with the sub.

[0] https://bleav.com/shows/what-am-i-doing-here-with-mike-reiss...

[1] https://twitter.com/Pogue/status/1671524465736335366

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

#49
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…

I'd imagine that location is the second most acoustically monitored part of the Atlantic (looking for ruskie subs coming from the north).

https://en.wikipedia.org/wiki/SOSUS

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

#50
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...

How do submarines commonly fail? Is the assumption of a violent implosion warranted?

I would think another failure mode could be water rushing in without the overall structure catastrophically failing, which would actually relieve pressure on the structure as it happened and be much less energetic.

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