Tourist submarine missing!

[tjh290633]

It's not clear to me that the wreckage needs to be recovered (even if that's practical) to ascertain what went wrong. From the info we've heard from the experts in the field It sounds like it's known what went wrong already and a desk investigation (along with possibly some lab tests) might well be sufficient.

We might be 99% sure of 99% of what went wrong but not 99.9% without recovering the bits. The extra knowledge gained may not be useful to deep-sea submarine builders (we already know that carbon fibre is not considered suitable) but it may be useful elsewhere.


Julian F. G. W.

Doesn't the size of the fragments matter? If they are very small, would they yield any useful information?

TJH

[jfgw]

Doesn't the size of the fragments matter? If they are very small, would they yield any useful information?

That information alone could be very useful.

I would expect there to be other information that could be gathered. Did it collapse from the middle or at the seams?


Julian F. G. W.

[mc2fool]

Doesn't the size of the fragments matter? If they are very small, would they yield any useful information?

That information alone could be very useful.

I would expect there to be other information that could be gathered. Did it collapse from the middle or at the seams?

Yes, that may be so, but will it be worth the considerable cost, difficulty and not to mention risk of the recovery? This isn't like a terrestrial aircraft crash where it's possible to spend weeks scouring the area for every tiny fragment, and indeed where they're unlikely to move...

[SimonS]

The testing of composite materials is notoriously difficult, so it is easy to Rush either as a risktaker on the grand scale or as a person who has satisfied himself the he has mitigated the risk but those without experience and set in their ways won't see that

There's a point where the vessel has been seen to work and is therefore 'reliable'.

But perhaps that's not the case if, every time that it's 'seen to work', the extreme stress-cycling of the pressure-vessel is actually slightly weakening it until it eventually simply loses it's capacity to cope with those immense pressures...

I suspect it would be a brave man who would bet against such an issue being the reason for failure in this terribly sad case...

Cheers,

Itsallaguess

Today an acquaintance told me of a conspiracy theory that seemed proof to him that something was going on and the establishment was covering it up. Apparently there's a website run by Ocearch who track sharks, including some very large Great Whites like Nukumi (17 feet long, allmost as big as "JAWS" (the movie star).

Normally these sharks follow well defined patterns but shortly before the Titan disappeared a couple of sharks headed out to the area of the Titanic and just after the incident the company removed their tags from the website...Duh...Duh Duh etc.

Of course if it is true, the company probably removed the tags because they could foresee that searchers after truth would demand the sharks be found, killed and gutted, because as we know big sharks can eat small cars.

So my money has moved from accident to a megalodon, chased from its abyssal home by the noise we humans make constantly, engines, propellors, sonar, depth sounders and endless submarines, crushing the hul, because these things are ike nuts, crunchy on the outside but deliciousl i the middle.

And yes, the movie has been made!

[ReformedCharacter]

The testing of composite materials is notoriously difficult, so it is easy to Rush either as a risktaker on the grand scale or as a person who has satisfied himself the he has mitigated the risk but those without experience and set in their ways won't see that

There's a point where the vessel has been seen to work and is therefore 'reliable'.

But perhaps that's not the case if, every time that it's 'seen to work', the extreme stress-cycling of the pressure-vessel is actually slightly weakening it until it eventually simply loses it's capacity to cope with those immense pressures...

I suspect it would be a brave man who would bet against such an issue being the reason for failure in this terribly sad case...

Cheers,

Itsallaguess

I read today that Branson's Virgin Galactic's Unity 25 is about to resume commercial flights. I wouldn't put the risk of disaster in the same bracket as the Titan but I wouldn't trust it myself. Stress-cycling of composite materials is a major issue IMO.

But since the float there have been fresh setbacks. In 2021, a book about the company – Test Gods: Virgin Galactic and the Making of a Modern Astronaut – reported that a test flight conducted two years earlier had resulted in serious damage. The book, by journalist Nicholas Schmidle, quoted Todd Ericson, the company’s former safety lead who later resigned, as saying: “I don’t know how we didn’t lose the vehicle and kill three people.”

https://www.telegraph.co.uk/business/2023/06/26/sir-richard-branson-poised-space-tourism-virgin-galactic/

I hope I'm wrong but it wouldn't surprise me to see a disastrous outcome from one of these launches. I can't really understand why such a business attracts investors either, I can't imagine the profit per trip to be sufficient to cover the development and operating costs and it only takes one accident and the the business is probably finished for good.

RC

[stewamax]

Doesn't the size of the fragments matter? If they are very small, would they yield any useful information?

That information alone could be very useful. I would expect there to be other information that could be gathered. Did it collapse from the middle or at the seams?

I am old enough to remember the de Havilland 106 Comet disasters. As the first jet airliner with a fresh and elegant design, the Comet fuselage underwent really thorough testing, but in use experienced structural failure due to metal fatigue: after a few flights the planes just broke up mid-air.

I always wanted a Dinky Toy Comet, and was green with envy when one of my friends managed to get one.

[stevensfo]

How fast would they have died?

Sorry about the morbid question, but my nephew is the same age as the poor 19-year old who died, and he was asking about this the other day, rather anxiously. Probably watched too many horror films!

I assume that at that depth and pressure, they would have been unconscious within seconds. I hope so! I'd like to put his mind at rest.

Steve

PS I'm a Biologist, so he thinks that I know about things like this.

[ReformedCharacter]

How fast would they have died?

Sorry about the morbid question, but my nephew is the same age as the poor 19-year old who died, and he was asking about this the other day, rather anxiously. Probably watched too many horror films!

I assume that at that depth and pressure, they would have been unconscious within seconds. I hope so! I'd like to put his mind at rest.

Steve

PS I'm a Biologist, so he thinks that I know about things like this.

Apparently it would have taken about 1ms for complete bodily destruction as the submersible imploded, followed by an explosion as the air rapidly heated aided by the hydrocarbons in the composite materials. So an implosion then an explosion, leaving the bodies as ash and dust. Since it apparently takes 25ms for the instinctive part of the brain to register anything then they wouldn't have been aware of what happened. Sorry I can't remember where I read the details.

RC

[Tedx]

I posted a BBC link a couple if days ago which suggested that death from a hull implosion would have occured faster than a human can think.

....of course they may passed out from carbon dioxide poisoning before that (as pointed out, C02 poisoning can induce a feeling of panic as the brain is deprived of oxygen.

[Tedx]

How fast would they have died?

Sorry about the morbid question, but my nephew is the same age as the poor 19-year old who died, and he was asking about this the other day, rather anxiously. Probably watched too many horror films!

I assume that at that depth and pressure, they would have been unconscious within seconds. I hope so! I'd like to put his mind at rest.

Steve

PS I'm a Biologist, so he thinks that I know about things like this.

Apparently it would have taken about 1ms for complete bodily destruction as the submersible imploded, followed by an explosion as the air rapidly heated aided by the hydrocarbons in the composite materials. So an implosion then an explosion, leaving the bodies as ash and dust. Since it apparently takes 25ms for the instinctive part of the brain to register anything then they wouldn't have been aware of what happened. Sorry I can't remember where I read the details.

RC

I guess the explosion would be similar to the way a diesel engine works. A rapid compression of hydrocarbons = heat = detonation.

[mc2fool]

How fast would they have died?

Well, if you google that question just about every report says instantly. One has to wonder if they had the Hollywood style horror of watching a hairline crack appear in the viewing port and grow, but...

"Though the Titan had a composite hull with inbuilt sensors that could withstand high pressures near the sea floor, any defect could result in a “near instantaneous implosion” in less than 40 milliseconds, said associate professor Eric Fusil, director of the Shipbuilding Hub at the University of Adelaide in Australia.

“The passengers probably would have had no idea what happened,” Bansil said."

https://abcnews.go.com/US/wireStory/catastrophic-implosion-titan-submersible-occupants-died-instantly-100346242

[stevensfo]

Thanks for the answers, guys. So very fast! That young man wouldn't have known much about it.

We all have to die.

It's just how and how long it takes that is scary!

Steve

[ReformedCharacter]

Titan submersible’s thrusters put on ‘backwards’ during terrifying 2022 trip:

Resurfaced footage shows the terrifying moment the Titan submarine’s thrusters stopped working during a 2022 expedition to the Titanic wreck. In an episode of the Travel Show on the BBC, a group of fee-paying visitors travel in the submersible to see the sunken liner.

“I’m thrusting and nothing is happening... One of the thrusters is thrusting backwards right now,” a crew member says.

The crew were told by OceanGate Expeditions CEO Stockton Rush to rotate the games controller used to steer the vehicle in order to go forwards...

Police in Canada announced on Saturday that they are considering a criminal investigation over the deaths of five men in the OceanGate submersible implosion.

https://www.independent.co.uk/news/world/americas/titanic-submarine-footage-implosion-sound-oceangate-latest-b2364026.html

RC

[XFool]

Emerging details on Titan sub reveal allegedly cavalier attitude toward safety

The Guardian

Experts had flagged safety problems with OceanGate’s vessels long before the doomed journey that killed five people

[ReformedCharacter]

Emerging details on Titan sub reveal allegedly cavalier attitude toward safety

The Guardian

Experts had flagged safety problems with OceanGate’s vessels long before the doomed journey that killed five people

Karl Stanley, who was on the Titan for an expedition near the Bahamas in April 2019, said he heard troubling noises during its voyage...“What we heard, in my opinion … sounded like a flaw/defect in one area being acted on by the tremendous pressures and being crushed/damaged.”

RC

[mc2fool]

Emerging details on Titan sub reveal allegedly cavalier attitude toward safety

The Guardian

Experts had flagged safety problems with OceanGate’s vessels long before the doomed journey that killed five people

Errr ... the Guardian seems to be a couple of weeks behind on this: experts were on BBC & Ch4 News (and undoubtedly other media) saying they'd warned OceanGate and talking about Rush's cavalier attitude from pretty much the moment it disappeared.

[XFool]

Errr ... the Guardian seems to be a couple of weeks behind on this: experts were on BBC & Ch4 News (and undoubtedly other media) saying they'd warned OceanGate and talking about Rush's cavalier attitude from pretty much the moment it disappeared.

So was The Guardian at the time, IIRC. Indeed there is a link in that article to an earlier Guardian report (21 June). This is an update, with extra details.

[bungeejumper]

For reference, here's the New Yorker article, dated 1st July:

https://www.newyorker.com/news/a-report ... -to-happen

Worried, given its seemingly crude design and lack of redundant safety features, McCallum told the magazine that “there were multiple points of failure”, including that its control system used Bluetooth. “Every sub in the world has hardwired controls for a reason – that if the signal drops out, you’re not [expletive deleted].” Cyclops I got stuck during a shallow-water test dive.

BJ

[mc2fool]

Emerging details on Titan sub reveal allegedly cavalier attitude toward safety

The Guardian

Experts had flagged safety problems with OceanGate’s vessels long before the doomed journey that killed five people

Errr ... the Guardian seems to be a couple of weeks behind on this: experts were on BBC & Ch4 News (and undoubtedly other media) saying they'd warned OceanGate and talking about Rush's cavalier attitude from pretty much the moment it disappeared.

So was The Guardian at the time, IIRC. Indeed there is a link in that article to an earlier Guardian report (21 June). This is an update, with extra details.

AFAICS the only extra details are that it reportedly dropped weights at some point during its descent, but it looks like the Guardian has realised that the allegedly cavalier attitude and experts flagging safety problems aren't news (and nothing to do with the emerging details anyway) as they've changed both the title and strap line for the article that you quoted, with neither of them appearing any more.

[bungeejumper]

Another incisive little gem from the New Yorker piece:

Another “mission specialist” wrote in a blog post that, a month before the implosion, Rush had confessed that he’d “gotten the carbon fiber used to make the Titan at a big discount from Boeing because it was past its shelf-life for use in airplanes.”

BJ