OceanGate Expeditions Titan DSV loss

[GeorgeA]

Plus submarines don't fall from the sky crashing people and properties downrange, so there is no FAA watchdog there.

Who would be in charge of certifying a vessel, then? The Coast Guard/Department of Transportation (equivalent) of whichever country the boat is registered in?

https://www.nytimes.com/2023/06/20/us/oceangate-titanic-missing-submersible.html (paywalled)

The separate warning that OceanGate received that same year came from 38 experts in the submersible craft industry; all of them were members of the Manned Underwater Vehicles committee of the Marine Technology Society, a 60-year-old industry group that promotes, studies and teaches the public about ocean technology. The experts wrote in their letter to Mr. Rush that they had “unanimous concern” about the way the Titan had been developed, and about the planned missions to the Titanic wreckage.

The letter said that OceanGate’s marketing of the Titan had been “at minimum, misleading” because it claimed that the submersible would meet or exceed the safety standards of a risk assessment company known as DNV, even though the company had no plans to have the craft formally certified by the agency.

“Their plan of not following classification guidelines was considered very risky,” Will Kohnen, the chairman of the committee, said in an interview on Tuesday.

The industry leaders said in their letter that OceanGate should, at minimum, test its prototypes under the watch of DNV or another leading certification company.

The vehicle was intended to operate in international waters only, so it was not technically required to seek certification from the USCG or other authorities.

 

[Michel Van]

US Coast Guards say they found a Debris field found near Titanic
unclear for moment what of debris

View: https://www.youtube.com/watch?v=XmYhuUDPT3M

 

[Fluff]

BBC says its from the sub, the landing gear etc.

https://www.bbc.co.uk/news/live/world-us-canada-65967464

 

[Orionblamblam]

"Debris field" is not generally what one associates with "intact pressure vessel." Odds increasing that it imploded.

 

[Dilandu]

So it was implosion. At least, they didn't have time to feel anything...

 

[The K2]

Then again, Mr Rush got away with it ...

At this point, it seems likely that he *didn't* get away with it.

It appears the Titan had a catastrophic failure where it could have imploded. Wouldn’t SOSUS pick this up?

 

[Michel Van]

There confirmation that debris are the Landing frame and rear cover of Titan

View: https://www.youtube.com/watch?v=CRd13ABoKrk

 

[Archibald]

They are dead. R.I.P to them. Even to the idiot that caused that waste of life. My bet is on implosion triggered by - surprise surprise ! - the window. As warned by the guy they fired immediately thereafters.

View: https://www.youtube.com/watch?v=Sj9MEwjkxE0

 

[Orionblamblam]

Then again, Mr Rush got away with it ...

At this point, it seems likely that he *didn't* get away with it.

It appears the Titan had a catastrophic failure where it could have imploded. Wouldn’t SOSUS pick this up?

You'd certainly think so. This implosion in "The Abyss" was similar, though far FAR less energetic. I suspect that the air was compressed hot enough to begin dissociating, though there wasn't time for it.

View: https://youtu.be/FkhBPF4yfkI?t=53




I wouldn't think that the sub would just start shedding components while the pressure vessel just slowly leaked; if there are chunks scattered about, there should have been an Earth-shattering kaboom.

 

[edwest4]

The pilot and 4 passengers of the Titan submersible are dead, US Coast Guard says

The U.S. Coast Guard says a missing submersible imploded near the wreckage of the Titanic, killing all five people on board.

www.detroitnews.com

 

[Justo Miranda]

USS Thresher (SSN-593) - Wikipedia

en.wikipedia.org

 

[Archibald]

USS Thresher (SSN-593) - Wikipedia

en.wikipedia.org

USS Scorpion (SSN-589) - Wikipedia

en.wikipedia.org

And, the same year (well, the same spring, or close !) 1968: one Soviet, one Israeli, and one French submarine. All sunk with all hands.

 

[Archibald]

"Show must go on" I told you they would spin the story as "heroic" even if they died. Didn't took long.
(facepalm)

Rush, the OceanGate executive who is on board the missing Titan submersible with four other people, is an intelligent explorer who is adept at managing risk, according to longtime friends.

Rush is "one of the most risk-averse people I know,” said Guillermo Söhnlein, who co-founded OceanGate.

Söhnlein said he last spoke with Rush about two weeks before the Titan’s expedition, its third to the Titanic site. Rush did not express any worries about the upcoming voyage.

“If anything, it’s the other way around,” Söhnlein said. “Any explorer will always tell you that on every expedition, on every mission, on every dive, something always goes wrong. You have to anticipate that something is going to go wrong. And the more guides you conduct, the more missions you conduct, the more expeditions you do, the more you start limiting those things.”

Another friend, oceanographer Gregory Stone, said Rush was upfront about the dangers of his missions.

“He wasn’t selling tickets like it was Disneyland. He was telling people exactly what it was — it was a dangerous thing,” Stone said. “He had taken every precaution possible, and he got unlucky. Something happened.”

 

[Orionblamblam]

... he got unlucky. Something happened.”

Well, no ᛋᚺᛁᛏ. You can always rely on people saying the blatantly obvious and the blisteringly inane in situations like this. Or when someone gets arrested.

 

[Michel Van]

my deepest sincere condolences to Family of victims

View: https://www.youtube.com/watch?v=__edp8NgPx0

 

[Scott Kenny]

Then again, Mr Rush got away with it ...

At this point, it seems likely that he *didn't* get away with it.

It appears the Titan had a catastrophic failure where it could have imploded. Wouldn’t SOSUS pick this up?

I'd expect so, but then you'd have to get the data out of the USN and to the USCG.

SOSUS certainly detected the implosions of Thresher in 1963 and Scorpion in 1968.

I wouldn't think that the sub would just start shedding components while the pressure vessel just slowly leaked; if there are chunks scattered about, there should have been an Earth-shattering kaboom.

There's no such thing as a slow leak under than much pressure!!!!!

375 atmospheres, 5500ish psi. According to this calculator, a 1/4" diameter pipe 4" long would put 18,230lbs/second of water into the sub. Doubling the pipe length halves the delivery. 375atm beginning pressure, 1atm ending pressure, dynamic viscosity of 0.0018Pa/s, liquid density of 1000kg/m^3.

 

[Orionblamblam]

I wouldn't think that the sub would just start shedding components while the pressure vessel just slowly leaked; if there are chunks scattered about, there should have been an Earth-shattering kaboom.

There's no such thing as a slow leak under than much pressure!!!!!

Sure there is. Not 1/4", but damn near molecular-scale. Leaking past a *slightly* imperfect seal. Or, hell, between the fibers in a fiber-wound hull.

That's vanishingly unlikely to be the problem here. Most likely, the most anybody on the sub got out was "Huh?" before they were squished. This failure was doubtless *amazingly* fast.

 

[Orionblamblam]

375 atmospheres, 5500ish psi. According to this calculator, a 1/4" diameter pipe 4" long would put 18,230lbs/second of water into the sub. Doubling the pipe length halves the delivery. 375atm beginning pressure, 1atm ending pressure, dynamic viscosity of 0.0018Pa/s, liquid density of 1000kg/m^3.

View: https://www.youtube.com/watch?v=oHC1230OpOg


I entered those numbers and got a very different result... several orders of magnitude lower mass flow rate... 18.23 pounds a second, not eighteen *Thousand* pounds a second.

 

[Scott Kenny]

375 atmospheres, 5500ish psi. According to this calculator, a 1/4" diameter pipe 4" long would put 18,230lbs/second of water into the sub. Doubling the pipe length halves the delivery. 375atm beginning pressure, 1atm ending pressure, dynamic viscosity of 0.0018Pa/s, liquid density of 1000kg/m^3.

(image deleted for space)

I entered those numbers and got a very different result... several orders of magnitude lower mass flow rate... 18.23 pounds a second, not eighteen *Thousand* pounds a second.

Having personally seen just how much water flows out of a 1/4" hole at 325+psi in the submarine flooding Damage Control trainer, yes, I am confident in those numbers I posted.

Did you match the units I used for each entry? because I had to change units on several of those fields.

Edit:
375atm starting pressure
1atm ending pressure
0.25" diameter
4" length
.0018 Pa*s dynamic viscosity
1000 kg/m^3 liquid density

Flow Rate Calculator (Pipe flow calculator)

Free online Flow Rate calculator which helps you calculate the flow rate of any pipe given its diameter and liquid/gas velocity or its height and width (for a rectangular pipe) and velocity. ➤ Calculate flow rate from pressure. Fluid flow rate through pipe given pressure difference at two...

www.gigacalculator.com

 

[Scott Kenny]

That's vanishingly unlikely to be the problem here. Most likely, the most anybody on the sub got out was "Huh?" before they were squished. This failure was doubtless *amazingly* fast.

Any implosion happens faster than the brain can process the information. under (edit) 0.002sec for total event time. That's (edit) 2 milliseconds, if you prefer that unit.

(edited: my memory was wrong. single digit milliseconds!)

 

[Moose]

https://twitter.com/x/status/1671998892550782982

View: https://twitter.com/WSJ/status/1671998892550782982?t=yFY5GOBjiJ-OmnLMZG8WWg&s=19

 

[Orionblamblam]

Did you match the units I used for each entry? because I had to change units on several of those fields.

Edit:
375atm starting pressure
1atm ending pressure
0.25" diameter
4" length
.0018 Pa*s dynamic viscosity
1000 kg/m^3 liquid density

Flow Rate Calculator (Pipe flow calculator)

Free online Flow Rate calculator which helps you calculate the flow rate of any pipe given its diameter and liquid/gas velocity or its height and width (for a rectangular pipe) and velocity. ➤ Calculate flow rate from pressure. Fluid flow rate through pipe given pressure difference at two...

www.gigacalculator.com

Well, *something* is squirrely. I used exactly the setup you gave, but changed the density to 1 gram per cubic centimeter... which is the same as 1000 kg/cubic meter, and lo and behold, the computer dun had isself a brain fart:

 

[Scott Kenny]

Did you match the units I used for each entry? because I had to change units on several of those fields.

Edit:
375atm starting pressure
1atm ending pressure
0.25" diameter
4" length
.0018 Pa*s dynamic viscosity
1000 kg/m^3 liquid density

Flow Rate Calculator (Pipe flow calculator)

Free online Flow Rate calculator which helps you calculate the flow rate of any pipe given its diameter and liquid/gas velocity or its height and width (for a rectangular pipe) and velocity. ➤ Calculate flow rate from pressure. Fluid flow rate through pipe given pressure difference at two...

www.gigacalculator.com

Well, *something* is squirrely. I used exactly the setup you gave, but changed the density to 1 gram per cubic centimeter... which is the same as 1000 kg/cubic meter, and lo and behold, the computer dun had isself a brain fart:

View attachment 702097

okay, need to find a new calculator for this, as that calc is obviously fubar.

 

[Scott Kenny]

Okay, using a Nozzle Flow rate calculator, 5500psi out of a 0.25in nozzle, I get 134.1gallons/min. This is a specifically water based calculator.

That's about 1072lbs/min of water, at 8lbs/gallon.

 

[Orionblamblam]

okay, need to find a new calculator for this, as that calc is obviously fubar.

It's off by a fact of a thousand on one of those inputs. Thing to do would be to run *all* the density input options, using the same basic density of water for each and see what happens. With luck *one* setting will prove screwy.

Me? Too lazy. Can't be bothered.

 

[Orionblamblam]

That's vanishingly unlikely to be the problem here. Most likely, the most anybody on the sub got out was "Huh?" before they were squished. This failure was doubtless *amazingly* fast.

Any implosion happens faster than the brain can process the information.

Oh, sure. But sometimes there is a bright, cheerful cracking sound just before the implosion. Long enough to wake up your brain to the fact of its immanent demise.

 

[Scott Kenny]

https://twitter.com/x/status/1671998892550782982

View: https://twitter.com/WSJ/status/1671998892550782982?t=yFY5GOBjiJ-OmnLMZG8WWg&s=19

Expected as much. SOSUS is incredibly capable. "The combination of location within the ocean and the sensitivity of arrays allowed the system to detect acoustic power of less than a single watt at ranges of several hundred kilometres." (from wiki) Tom Clancy said that the Ohio-class subs radiated about as much energy as a 40 watt lightbulb into the water, and Ohios are ghosts.

https://twitter.com/x/status/1671998892550782982

View: https://twitter.com/WSJ/status/1671998892550782982?t=yFY5GOBjiJ-OmnLMZG8WWg&s=19

Or, you know, they needed to get "yes we detected an implosion" declassified so they could say it to the news. The very existence of SOSUS arrays was classified until 1991, and it had been operational since the mid 1950s.

 

[Orionblamblam]

"distraction op"? Uh huh. And once the "distraction" ends, does it take away any attention from anything that's still going on?

Yes. People forget/lose interest pretty quick.

 

[edwest4]

"distraction op"? Uh huh. And once the "distraction" ends, does it take away any attention from anything that's still going on?

Yes. People forget/lose interest pretty quick.

Depending on the magnitude of that other thing - no, they don't. Especially if it turns into a constantly repeated talking point for the 'other side.' Dog needs a bone and won't let go...

 

[Rhinocrates]

James Cameron discusses the material and engineering issues from about 5:30. Main points: carbon composite is totally unsuitable material because its suited for internal pressure rather than external pressure (that is, it has excellent tensile strength but not so much for compression or buckling if it delaminates); repeated pressure cycling of a composite material (instead of steel) is going to lead to degradation - specifically, water ingress leading to delamination.

'These are known things, they're known within the engineering community.'

Carbon fibre composites rely on multiple layers of an otherwise flexible material (it's essentially a woven cloth) being securely bound to each other by the resin matrix. Bending would require them to move slightly in relation to each other. If they cannot move because they are bound in a resin matrix, they won't bend easily. You can demonstrate this by gluing two or more sheets of paper together - it becomes stiff. If water gets in, the layers can become detached from one another, allowing the structure to buckle. Repeated cycles of compression and decompression may well have led to fatigue and cracking in the matrix, allowing water to get in between the layers and separating them.

View: https://www.youtube.com/watch?v=5XIyin68vEE

 

[Rhinocrates]

On top of the tragedy, there's the depressing certainty that conspiracy theories are going to proliferate. People are going to fixate on the supposed banging heard.

There are plenty of these vermin gathering about the wreck of the Titanic itself, like flies on a corpse.

The Titanic Truthers of TikTok

On the short-form video app, long-established facts about the 1912 disaster at sea are being newly litigated as musty rumors merge with fresh misinformation and manipulated content.

www.nytimes.com

 

[Orionblamblam]

Some really rich people have vanished. Even if their bodies can be recovered (which I doubt), it's beyond unlikely that they will be identifiable, apart from DNA. That sort of thing is *always* going to bring out the cranks.

 

[publiusr]

Indeed. I would be curious about the exact conditions (financial and otherwise) of the Space Act Agreement between OceanGate and NASA MSFC for the development of the carbon fiber structure. Follow the money...

MSFC worked with these clowns?

When SLS launched and Super heavy blew chunks, I thought my state was BACK.

And now--this.

If carbon can fail from pressure outside-in, then what about the plans to have SRB steel caissons replaced with 'fiber? Might that be an inside out failure?

Was it the same people?

Good grief.

I hope the end was fast... with no one getting porcupined with carbon splinters to the face beforehand.

I was so proud of MSFC as just a member of the sidewalk alumni.


I don't know what to believe now.

 

[1635yankee]

The properties of a composite in compression tend to be dominated by the matrix properties. I suspect they'll find the pressure vessel failed where the composite cylinder was joined to the spherical end.

 

[Archibald]

I do hope they savagely savage the company and the co-founder. Waivers my sorry a$$, if that submarine was a coffin, they have to pay. So far we know they cut corners on things like
- composites instead of steel or titanium
- the window not build to the correct depth pressure
- the hatch that couldn't be opened from the inside

Titanic sub: victims' families could still sue despite liability waivers

Liability waivers signed by passengers on a submersible lost at sea during a dive to the Titanic wreck may not shield the vessel's owner from potential lawsuits by the victims' families, legal experts said.

www.reuters.com

There will be blood.

 

[quellish]

The properties of a composite in compression tend to be dominated by the matrix properties. I suspect they'll find the pressure vessel failed where the composite cylinder was joined to the spherical end.

Given that the tail section - which was not at 1atm - was found with ballast in location 1, while the front titanium cap and porthole were found several hundred meters away, it does sound like the carbon fiber cylinder failed. That they may never find as it would be tiny shards.

 

[publiusr]

The wreck of the Titanic itself may have been further damaged in what amounted to a depth charge.

 

[MrTopaz]

I do hope they savagely savage the company and the co-founder. Waivers my sorry a$$, if that submarine was a coffin, they have to pay. So far we know they cut corners on things like
- composites instead of steel or titanium
- the window not build to the correct depth pressure
- the hatch that couldn't be opened from the inside

Titanic sub: victims' families could still sue despite liability waivers

Liability waivers signed by passengers on a submersible lost at sea during a dive to the Titanic wreck may not shield the vessel's owner from potential lawsuits by the victims' families, legal experts said.

www.reuters.com

There will be blood.

I‘m not a lawyer, but I gotta imagine that the liability waiver wouldn’t stand up. Like, it’s one thing to have a waiver that says, “I know that what I’m doing is extremely dangerous, if not probably fatal, even under the most advantageous circumstances, and I won’t sue if things go wrong on the ‘things will probably go wrong’ mission.” It’s quite another to say the piece of paper you yourself drafted indemnifies you from the consequences of what looks like obvious neglect on your part. Especially in light of the fact that they fired the engineer who raised red flags about the design.

But then I wonder if any legal action would be dependent on an analysis of the wreckage, which would require a difficult salvage, to say the least.

 

[Flyaway]

Cameron is spot on you don’t use an experimental sub made of a material that’s never been used at those depths to carry paying passengers. I mean it’s better for space than the seas being as there the pressure is internal not external.

Investigations under way into loss of Titan sub as questions grow over its design

Concerns raised over craft’s safety standards and lack of certification as US Navy reports likely implosion

www.theguardian.com

 

[Orionblamblam]

The properties of a composite in compression tend to be dominated by the matrix properties.

Indeed. Rather than being a "carbon fiber" structure, for all practical purposes it was a "phenolic resin" or "epoxy resin" structure. Which I would not go underwater in on a dare.