Titanic tourist sub goes missing sparking search

[lowwall]

How much more expensive would it have been to make the carbon fiber part out of titanium like the endcaps? Or weight becomes issue?

It's weight. The system becomes much more expensive and complex because it's so much heavier and denser. This is from an excellent 2019 article in Smithsonian magazine A Deep Dive Into the Plans to Take Tourists to the 'Titanic'

"The weight of steel and titanium subs makes them expensive to transport on land and requires large ships, outfitted with cranes, to launch at sea. Because of their heft, traditional subs tend to require bulky, syntactic foam flotation blocks to maintain neutral buoyancy, which is crucial for maneuverability. Titan, by contrast, is much cheaper to transport and launch, and without the foam is nimbler in the water."

 

[HalcyonDaze]

A sphere is the strongest..

The long cylindrical part is the weakest.

Carbon fiber is said to be 5 inches thick..... there seems to be no bulkhead in that sub,
so chances are that the middle of that tube is what buckled,

I am surprised that it gave them warning, If its true that they where emergency ascending...

I would hate to know what the titanium end caps are worth...
A tube 5inchs thick???? No idea

The one other way I've seen to make a longer pressure hull is to build it as a chain of spheres connected by hatchways; the USN Mystic-class DSRVs had 3 spheres making up the pressure hull while the Russian Losharik-class small nuclear submarine has a chain of seven titanium spheres (hence the name, after a Soviet cartoon character).

 

[wetb4igetinthewater]

I am a bit sad about all some of the comments and the blame, even from James Cameron who himself went to Challenger Deep (way deeper) with an experimental vessel that had less previous dives than Titan (28 people dove to the Titanic with Titan). Of course, the big difference is that he was only risking his own life and did not have 4 passengers who signed a waiver stating that dying was a possibility and that the company would hold no responsibility. I am not knowledgeable enough to judge the metal vs composite thing but as techniques evolve I would not be surprised to see reliable and safe carbon fiber hulls in a few years or decades. Anyway, I have watched a lot of videos of the pilot those last 4 days and I think that we should acknowledge a few things. He never said that the vessel was safe as a commercial airplane or even a standard submarine. He was a pioneer and as such he might have made some mistakes, taken some shortcuts, been a risk taker but he was a true explorer. It is wrong to say that he wanted to launch a tourist business. He built the sub for research and exploration purposes and taking paying passengers was a way to finance that. Someone said that only those who don’t do anything don’t make mistakes. Stockton Rush probably made some mistakes. Lethal mistakes. He brought four people in death with him. He is not the first explorer and won’t be the last to push the envelope. Some have gotten away with it and are celebrated. Others died or caused death. The guy was flawed but he was an explorer, not a criminal.

I have to ask, are you completely unaware of this:

https://int.nyt.com/data/documenttools/marine-technology-society-committee-2018-letter-to-ocean-gate/eddb63615a7b3764/full.pdf

and this:

OceanGate, company behind missing Titanic tourist sub, once subject of lawsuit over safety complaints

OceanGate once faced a lawsuit from a former employee who alleged they were fired for raising safety concerns about the vessel that went missing while descending to the Titanic.

www.foxbusiness.com

and this:

"Safety is just pure waste": Lost Titanic sub’s creator made chilling comment in 2022 interview as search becomes "bleak"

The boss of the firm that created the missing Titanic submarine gave an interview last year in which he said “at some point, safety is just pure waste”.

www.lbc.co.uk

the list goes on and on. You may not know people who were fired for adhering to safety requirements (I do) or people let go for bringing up safety issues (my boss knows 3).

There is no excuse for that. Sure, push the envelope, but compare James Cameron's expeditions to this one.

More talk about the joysticks for Titan

Here is the Microsoft Xbox game controller for $300K of equipment. I own the laser scanner and am renting the ROV.

 

[Dan]

Excellent new commentary by James Cameron. He gives a little more detail on the hydrophone info and quite a bit on why carbon composite is a poor material for this purpose.

I had similar conclusion early in the thread. At least they experienced sudden death, without suffering. RIP.

This would explain the sudden loss of communication when the sub almost reaching to the bottom, implosion.

 

[Dody]

I have to ask, are you completely unaware of this:

https://int.nyt.com/data/documenttools/marine-technology-society-committee-2018-letter-to-ocean-gate/eddb63615a7b3764/full.pdf

and this:

OceanGate, company behind missing Titanic tourist sub, once subject of lawsuit over safety complaints

OceanGate once faced a lawsuit from a former employee who alleged they were fired for raising safety concerns about the vessel that went missing while descending to the Titanic.

www.foxbusiness.com

and this:

"Safety is just pure waste": Lost Titanic sub’s creator made chilling comment in 2022 interview as search becomes "bleak"

The boss of the firm that created the missing Titanic submarine gave an interview last year in which he said “at some point, safety is just pure waste”.

www.lbc.co.uk

the list goes on and on. You may not know people who were fired for adhering to safety requirements (I do) or people let go for bringing up safety issues (my boss knows 3).

There is no excuse for that. Sure, push the envelope, but compare James Cameron's expeditions to this one.


Here is the Microsoft Xbox game controller for $300K of equipment. I own the laser scanner and am renting the ROV.
View attachment 789124View attachment 789125

Is that supposed to be a demonstration that the CEO committed a crime? Nothing to do with diving but… there were many more evidences of misconducts, concealments, lies to a federal agency, disregard to safety including people being fired for raising safety issues and so on and so forth in cases like Boeing 737 Max crashes that killed 346 people (not 5 even though there was no billionaire on board) because of the MCAS (no training and no information given to the pilots). Was there an excuse for that? Have those 346 casualties signed a waiver before boarding? Was Boeing CEO on board or counting beans at his office? Has anyone been prosecuted or at least given a slap on the wrist? No. Unacceptable conduct and crime look very much subjective after that.

 

[Gone for diving]

The one other way I've seen to make a longer pressure hull is to build it as a chain of spheres connected by hatchways; the USN Mystic-class DSRVs had 3 spheres making up the pressure hull while the Russian Losharik-class small nuclear submarine has a chain of seven titanium spheres (hence the name, after a Soviet cartoon character).

Yes that is one way..
But definitely not as roomy, and expensive for the square footage.

Which seems like one reason the cylindrical tube design was used...

We all need to remember the forces 5000 psi on a 4-5ft diameter tube will have,
it's one thing if its 4 inches in diameter.
5ft in diameter is totally crazy forces,

 

[lowwall]

The one other way I've seen to make a longer pressure hull is to build it as a chain of spheres connected by hatchways; the USN Mystic-class DSRVs had 3 spheres making up the pressure hull while the Russian Losharik-class small nuclear submarine has a chain of seven titanium spheres (hence the name, after a Soviet cartoon character).

Rush obviously truly believed in his carbon fiber composite tube. His background was in aerospace engineering where CF has been a revolutionary material for a couple of decades now. Given that familiarity and the incredible strength to weight properties of CF composites, it becomes possible to understand how he could have convinced himself that he could build in enough margin or come up with a warning system to overcome the sudden and catastrophic failure mode that is the Achilles' heel of carbon fiber.

But convincing himself should not have been enough when he decided to take on passengers. IMO, at that point the responsible thing to do would be to seek the appropriate classification for the vessel. Or at the very minimum to seek an engineering review from a third party with the appropriate deep sea experience.

 

[Dan]

It's weight. The system becomes much more expensive and complex because it's so much heavier and denser. This is from an excellent 2019 article in Smithsonian magazine A Deep Dive Into the Plans to Take Tourists to the 'Titanic'

"The weight of steel and titanium subs makes them expensive to transport on land and requires large ships, outfitted with cranes, to launch at sea. Because of their heft, traditional subs tend to require bulky, syntactic foam flotation blocks to maintain neutral buoyancy, which is crucial for maneuverability. Titan, by contrast, is much cheaper to transport and launch, and without the foam is nimbler in the water."

How about the cylindrical section made out of a thin titanium external cladded to carbon composite internal?

 

[HalcyonDaze]

Rush obviously truly believed in his carbon fiber composite tube. His background was in aerospace engineering where CF has been a revolutionary material for a couple of decades now. Given that familiarity and the incredible strength to weight properties of CF composites, it becomes possible to understand how he could have convinced himself that he could build in enough margin or come up with a warning system to overcome the sudden and catastrophic failure mode that is the Achilles' heel of carbon fiber.

But convincing himself should not have been enough when he decided to take on passengers. IMO, at that point the responsible thing to do would be to seek a commercial rating for the vessel. Or at the very minimum to seek an engineering review from a third party with the appropriate deep sea experience.

Anyone know the total number of full-depth dives the sub made? Near as I can tell they did a shallow crewed dive in Puget Sound initially, then shipped it to the Bahamas for at least three or four full-depth tests between June 2018 and January 2020, at which point the carbon fiber hull was de-rated to 3000 meters due to fatigue signs and then either repaired or replaced prior to starting dives on the Titanic site in 2021. It seems like they did six dives on Titanic in 2021, seven in 2022, and this was the first dive of 2023.

 

[lowwall]

Is that supposed to be a demonstration that the CEO committed a crime? Nothing to do with diving but… there were many more evidences of misconducts, concealments, lies to a federal agency, disregard to safety including people being fired for raising safety issues and so on and so forth in cases like Boeing 737 Max crashes that killed 346 people (not 5 even though there was no billionaire on board) because of the MCAS (no training and no information given to the pilots). Was there an excuse for that? Have those 346 casualties signed a waiver before boarding? Was Boeing CEO on board or counting beans at his office? Has anyone been prosecuted or at least given a slap on the wrist? No. Unacceptable conduct and crime look very much subjective after that.

Whataboutism - Wikipedia

en.m.wikipedia.org

Boeing management getting away with what certainly appears to be negligent homicide has nothing to do with this event.

You stated Rush was a pioneer, not a criminal. I'll agree with a label of explorer, but not pioneer as it is highly unlikely anyone else will be following his path. I also believe he was culpable of the deaths of his passengers through negligence. This makes him a criminal in my eyes even though he will never be convicted in a court of law.