Titanic tourist sub missing

[jimbob]

In principle carbon fibre would be a totally acceptable material for that centre tube. We had a discussion about this yesterday. Basically, assuming that the tube was constructed out of properly-layered (ie at specific different angles per sheet overlay) CF with epoxy resin binders (standard for CF), and provided it was cured properly in an autoclave, it should have been extremely resilient to both compression and tension.

The problem, however, is that the laminate substrate flexes every time the sub descends and ascends. This can cause fatigue in the resin layer, and eventual delamination. Once a section of the tube becomes seriously delaminated, it's a prime candidate for compressive failure.

I was suggesting yesterday that at a bare minimum - given the massively extreme operating conditions of this vessel - the sub should have been completely stripped down after every voyage and very carefully checked over before reassembly, including ultrasound/x-ray checks of the carbon fibre hull tube. And I also suggested that a prudent operator might well consider completely replacing that CF centre tube after every 2-3 voyages. From the sounds of things, I don't think this level of scrutiny in maintenance was ever applied to the Titan.....

I get uneasy about almost every interface in the silicon and Gallium Nitride chips I design, and that's just from simple thermal cycling as the main driver.

A Carbon fibre tube, 5" thick (what France 24 was reporting) would be very interesting to test. And then you have the endpieces, which must have very challenging stresses, and significantly different at the surface and deep water, hence my comments about interfaces.

And I still say that designing for testability is part of safety-critical reliability.

 

[Dr.Sid]

SO help me , James Cameron has become the go to interview as an "expert" on this.
It is like interviewing somebody who chartered and then flew as a passenger in a 747 as an expert on aeronautics.
God, I hate the age of Celebriity.

Why though ? Enjoy stupidity. It's everywhere, if you will hate it, you're not gonna have a good time.
Also the fact that somebody asks James Cameron for opinion is pretty harmless, compared to stuff we learned during these few days.

 

[lobosrul5]

Social media wanted a say and did not disappoint, delivering the absurd subplot that we all deserved. One of the missing passengers is Hamish Harding, a British billionaire and adventurer. His stepson announced that he was going to a Blink-182 concert for solace and tweeted his plight to band members. Cardi B was having none of it. She posted a video on Instagram that addressed people who suggested that a guy going to and posting about a Blink-182 concert while his stepdad was missing was completely normal behavior:

“You’re supposed to be at the house sad. You’re supposed to be crying for me. You’re supposed to be right next to the phone waiting to hear any updates about me, you’re supposed to be consoling your mommy. Isn’t it sad that you are whole *********** billionaire, and nobody gives a **** about you? Like you missing and ************* are ready to shake dicks at concerts. That’s crazy. I rather be broke and poor but knowing that I’m loved.”



https://variety.com/2023/tv/opinion/missing-titanic-sub-coverage-exploited-tragedy-1235652292/

 

[TellyKNeasuss]

Yes. In this small pressure hull, a catastrophic implosion would have reduced the crew's bodies to piles of mush almost immediately. The pressure of the imploding hull, and the force of matter hitting the crew (which would be a mixture of pieces of the CF tube travelling at extremely high speed, plus water travelling at extremely high speed) would have torn their bodies to bits. The energy involved in an implosion at these depths is absolutely awesome.

(The only reason why in certain implosion-based submarine losses some of the crew survived the implosion is because there are multiple waterproof pressure hatches in submarines and SOP is to keep them locked shut as much as possible. So, for example, when the Kursk exploded at the bow end (which caused a blowback implosion once the hull was breached by the explosion), the crewmembers who survived for several days were all at the back of the boat and behind a number of locked hatches.)

And the Kursk sank in water that was only 350 feet deep => water pressure of around 150 psi. The water pressure where the Titan imploded was likely at least 20 times that.

 

[pgwenthold]

And anybody who ran Sub Detection gear in the US navy can tell you, the "Silent Deep"is anything but silent

It could be a hot, crustacean band like in the Little Mermaid.

Under the sea, under the sea...darling it's better down where it's wetter, take it from me

 

[TellyKNeasuss]

The Denver Post has an article that states that the US Navy detected an "anomaly" on Sunday that likely was the implosion. They weren't certain enough, so the search was allowed to continue.

https://www.denverpost.com/2023/06/...maly-that-was-likely-implosion-official-says/

 

[Marcus]

The Navy is saying they heard the implosion (the first day, around the time contact was lost) on one of their top secret listening stations that monitor submarine activity. Not so top secret anymore, I guess. They didn't say why they waited so long to tell anyone.


https://www.wsj.com/articles/u-s-navy-detected-titan-sub-implosion-days-ago-6844cb12

 

[Orphia Nay]

They're all dead, Dave.

 

[TellyKNeasuss]

The Navy is saying they heard the implosion (the first day, around the time contact was lost) on one of their top secret listening stations that monitor submarine activity. Not so top secret anymore, I guess. They didn't say why they waited so long to tell anyone.


https://www.wsj.com/articles/u-s-navy-detected-titan-sub-implosion-days-ago-6844cb12

According to the Denver Post article, the Navy did tell the Coast Guard but their interpretation of the data lacked enough certainty to definitively conclude that the Titan had imploded.

 

[TellyKNeasuss]

Duplicate post deleted

 

[Skeptical Greg]

....The Not so top secret anymore, I guess.

Do you think no one knew they existed before this all went down?

The " top secret " part, is their operation procedures, not the fact that they exist.

 

[dudalb]

It could be a hot, crustacean band like in the Little Mermaid.

Under the sea, under the sea...darling it's better down where it's wetter, take it from me

Seriously, sorting out a submarine from other undersea noises is a real problem in detecting Submarines.

 

[dudalb]

Do you think no one knew they existed before this all went down?

The " top secret " part, is their operation procedures, not the fact that they exist.

This.

 

[Skeptical Greg]

It could be a hot, crustacean band like in the Little Mermaid.

Under the sea, under the sea...darling it's better down where it's wetter, take it from me

Now there's a euphemism I missed before.. Those Disney people are so naughty..

 

[dudalb]

Oh but Cameron now really does think he's a bona fide expert on all things related to Titanic and deep sea exploration in general.

I've seen Titanic-related programmes where he gathers in a panel of (true) experts and goes over the sinking and the discovery etc. And because he's paid for all the computer modelling and scale models and impressive graphics etc, they all effectively defer to his grandstanding.

At best James Cameron is a knowledgabel fan of deep sea navigation.
Me, I would rather listen to the pros.

 

[dudalb]

Talk to any sailor, the ocean just makes a lot of weird noises.

This, It drove the US sailors manning detection equipment trying to detect the noises made by Soviet subs crazy.

 

[Myriad]

Seriously, sorting out a submarine from other undersea noises is a real problem in detecting Submarines.

True.

Despite this, though, I do think that if the submersible had been intact underwater, and its crew really were banging on one of the titanium ends of the hull every half hour, and it was in the part of the ocean it was supposed to be, it would have been heard and located relatively quickly.

 

[Puppycow]

Seriously, sorting out a submarine from other undersea noises is a real problem in detecting Submarines.

For many years, the Swedes thought they were hearing Soviet submarines entering operating in their harbor waters. Turned out what they were hearing was fish farts.

https://www.iflscience.com/for-15-y...itory-it-turned-out-to-be-herring-farts-57782

 

[TragicMonkey]

This, It drove the US sailors manning detection equipment trying to detect the noises made by Soviet subs crazy.

"Comrade, why are you blowing vuvuzela against hull?"

 

[CORed]

You can drop steel or iron into the deepest oceans and its just going to be putting pressure on each side. Its not going to make enough difference to its shape for a human beings eyes to tell. Its when there is air, or another gas, contained inside a steel vessel that you will see implosion.

There probably was some implosion that occurred when Titanic sank, especially in the stern (bow sank more quickly IIRC). But most of it flooded before it imploded.

<--- my totally unscientific take, and someone like JayUtah I'm sure could do vastly better

Probably no implosion. That would only happen if there were some space completely sealed off from water intrusion, and I don't think there was. Otherwise, water will come in and any air trapped inside would be compressed to the water pressure.