Missing submersible near wreck of Titanic

[Mogster]

The Titan sub looked like it had been built in someone’s garage, the videos online of people being bolted inside the thing are a disturbing watch now. By comparison Alvin, the WHOI/US Navy operated sub, looks like a space vehicle.

It seems these type of craft tend to have the crew in a metal sphere, often titanium. Making the ends of this sub in titanium and the centre in composite just seems to introduce all sorts of fatigue issues when you think of the forces involved. You’d imagine the joint between the metal and composite is a serious area of weakness.

I do think the US Coast Guard was aware of the US Navy’s implosion suspicions and their apparent inaction was caused by this.

 

[Ediswan]

You’d imagine the joint between the metal and composite is a serious area of weakness.

That might be true, but I would be wary of presuming that it is. Glued joints can be stronger than the materials being joined. (The video linked earlier shows the joint being made.)

 

[Cowley]

I do hope things change and lessons are learnt from this. I thought this from James Cameron was quite an interesting quote:

Cameron also noted the similarities between the Titan and the Titanic, saying both tragedies were preceded by unheeded warnings.

"Here we are again," he said. "And at the same place. Now there's one wreck lying next to the other wreck for the same damn reason."

I’ve got quite an interesting little artefact at home that helped me as a kid to understand the pressures involved at the depths they were diving to.

My dad’s cousin Graham used to be a documentary maker for ITV - TVS (Television South) and was on the Jules Verne filming the documentary when Bob Ballard first dived down to the Titanic. On one of the dives they nicked a load of polystyrene cups from the cafeteria on the ship to write messages on before filling a net with them and tying them to the sub on one of the dives. A few of us in the family have these, here’s my one:


On it is written (although quite faded now) To Chris and Colin (my parents, although I’ve always been a little bit miffed that he didn’t add my name ) Joules Verne - Titanic dive 1986, plus the longitude and latitude.

As you can see by the size of it next to the lighter for scale, it’s had all of the air squeezed out of it on its trip to the bottom. It’s not much bigger than a thimble now!

 

[43066]

My dad’s cousin Graham used to be a documentary maker for ITV - TVS (Television South) and was on the Jules Verne filming the documentary when Bob Ballard first dived down to the Titanic. On one of the dives they nicked a load of polystyrene cups from the cafeteria on the ship to write messages on before filling a net with them and tying them to the sub on one of the dives. A few of us in the family have these, here’s my one:

That’s genuinely fascinating, and an extraordinary thing to possess.

As you can see by the size of it next to the lighter for scale,

For Christ’s sake keep it away from that lighter, especially after a few beers !

 

[Cowley]

For Christ’s sake keep it away from that lighter, especially after a few beers !

Good point!

Don’t worry, it’s back in the Cowley cupboard of strange things now, along with the passports and my collection of children’s teeth…

 

[Lloyds siding]

Good point!

Don’t worry, it’s back in the Cowley cupboard of strange things now, along with the passports and my collection of children’s teeth…

Your own passports I hope...and also your own childrens' teeth too.....

 

[Cowley]

Your own passports I hope...and also your own childrens' teeth too.....

Mostly.

 

[Trainguy34]

Your own passports I hope...and also your own childrens' teeth too.....

But that's no fun!

 

[SCH117X]

If Thunderbird Two had dropped its pod containing Thunderbird Four, that could dive to 35000 feet and would have been suitable for the rescue. That is in a hypothetical scenario where science fiction had become fact.

But given all the commentary on the appropriate shape for a deep sea vehicle being circular and not tubular how would successful would TB4 be?

 

[GS250]

Wasn't a fundamental flaw of Titan the fact that it was made of a Titanium Carbon Fibre composite? The issue being that carbon fibre gives absolutely no indicators of its health at high pressure? A metal hull gives off all kinds of measurable indicators that its stating to become overstressed.

I'm all for innovation but this just seems absolute negligence.

 

[AM9]

Should they have also stopped development of jet aircraft when the Comet failed? Clearly they should not. However it does seem more research and unmanned testing is required, and perhaps some more regulation to go with it.

The failure of the Comet fuselage was a structural issue arising from cyclic pressurisation and depressurisation causing metal fatigue, and nothing to do with the aircraft's propulsion mode.

Edit: Ooops! As @DerekC well explained the failure mode of the Comets, - i didn't notice that post.
As was said, the catastrophic failure of the submersible was caused by a complete abdication of legal and moral responsibilities to get independant assessment and certification of a novel design by it's high-handed designers driven by commercial gain ethics. The nearest equivalent in the aerospace world was Boeing's abuse of self-certification of the 737 Max design, in that instance the consequences were far more serious with the loss of 346 lives, none of whom were ever expected to share the risk of a so called certificated aircraft failing.

 

[baz962]

Some wreckage of the titan and possible human remains found.

 

[Jozhua]

Images of the parts being brought into port have been captured. A strap lifting the titanium front section seems to be going through the porthole window, which does make me wonder if it failed?

That said, the titanium front section seems to be in one solid piece still, unlike the minced sections of carbon fibre. Maybe if they'd made the whole submarine out of this ......

 

[swt_passenger]

Very odd description of the construction in a BBC article. They first write:

“The submersible's construction included at least one titanium end cap, a titanium ring and a carbon fibre cylinder.”

Then they write:

“The debris brought ashore on Wednesday appeared to include at least one titanium end cap, the sub's porthole with its window missing, as well as a titanium ring, landing frame and the end equipment bay, according to BBC science correspondent Jonathan Amos.”

Looks like they’ve made an error in the editing, mixing up what’s been recovered with how it was assembled, because surely it’s a matter of fact that there was a titanium hemispherical section at both ends?

Titanic tourist sub photos show wreckage being brought ashore

Pieces of the submersible are seen for the first time after being recovered from the Atlantic.

www.bbc.co.uk

 

[AM9]

Very odd description of the construction in a BBC article. They first write:

“The submersible's construction included at least one titanium end cap, a titanium ring and a carbon fibre cylinder.”

Then they write:

“The debris brought ashore on Wednesday appeared to include at least one titanium end cap, the sub's porthole with its window missing, as well as a titanium ring, landing frame and the end equipment bay, according to BBC science correspondent Jonathan Amos.”

Looks like they’ve made an error in the editing, mixing up what’s been recovered with how it was assembled, because surely it’s a matter of fact that there was a titanium hemispherical section at both ends?

Titanic tourist sub photos show wreckage being brought ashore

Pieces of the submersible are seen for the first time after being recovered from the Atlantic.

www.bbc.co.uk

Wasn't one end sperical with the window inset, and the other end tapered to an offset point?

 

[swt_passenger]

Wasn't one end sperical with the window inset, and the other end tapered to an offset point?

AIUI the taper section was only exterior cladding, hiding a lot of stuff that was mounted outside the pressure hull. There was a picture somewhere showing it under test with the tail end cladding removed, I’ll try and find it…

 

[156421]

Another thought is... who is paying for all of these recovery vehicles and crew from around the world? Will OceanGate be footing the bill?

 

[Peter Mugridge]

Images of the parts being brought into port have been captured. A strap lifting the titanium front section seems to be going through the porthole window, which does make me wonder if it failed?

It's been widely reported that the porthole was a type certified to a maximum depth of 1,500m so it would not be surprising if that turned out to be the main point of failure would it?

 

[Cowley]

It's been widely reported that the porthole was a type certified to a maximum depth of 1,500m so it would not be surprising if that turned out to be the main point of failure would it?

I’ve also heard that and the fact that it was seen visibly flexing. All in all even if half of the things said about the Titan turn out to be true, this incident was inevitable.

 

[ainsworth74]

It seems that whilst death will have been instantaneous (faster than they could even have known they were dying) they will have known something was very wrong if James Cameron is right:

He added that he had heard through “the community” that the Titan had dropped its ascent weights and was “trying to manage an emergency” when the implosion occurred.

“They probably had a warning that their hull was starting to delaminating and the hull was starting to crack,” Cameron told ABC News in an interview.

“We understand from inside the community that they had dropped their ascent weights and they were coming up, trying to manage an emergency,” the filmmaker said.

James Cameron knew of the Titanic sub implosion days before it was found. This is why

James Cameron’s insights into the Titan submersible tragedy caught many by surprise. But the ‘Titanic’ filmmaker has been immersed in the deep-sea exploration community for decades, Bevan Hurley writes

www.independent.co.uk

So a quick death but probably a terrifying final few minutes.

 

[Bletchleyite]

I’ve also heard that and the fact that it was seen visibly flexing. All in all even if half of the things said about the Titan turn out to be true, this incident was inevitable.

Things flexing is not unusual, I read somewhere that it was designed as a plug so would push harder into the hole it was blocking.

But if it flexes too much...

 

[Jozhua]

I’ve also heard that and the fact that it was seen visibly flexing. All in all even if half of the things said about the Titan turn out to be true, this incident was inevitable.

Very true! Seems like there wasn't one likely failure mode, but something like a hundred. Deducing which one actually led to the untimely demise of the sub will be a challenge, considering there are so many likely contenders.

It seems that whilst death will have been instantaneous (faster than they could even have known they were dying) they will have known something was very wrong if James Cameron is right:

James Cameron knew of the Titanic sub implosion days before it was found. This is why

James Cameron’s insights into the Titan submersible tragedy caught many by surprise. But the ‘Titanic’ filmmaker has been immersed in the deep-sea exploration community for decades, Bevan Hurley writes

www.independent.co.uk

So a quick death but probably a terrifying final few minutes.

The James Cameron explanation is probably right - In that case everybody on the ship must have known what happened well before the debris was discovered a few days later. They would have certainly been able to hear an audible bang, at least if standing outside. (The implosion energy is equivalent to something like 700kg of high explosives)

 

[ainsworth74]

The James Cameron explanation is probably right - In that case everybody on the ship must have known what happened well before the debris was discovered a few days later. They would have certainly been able to hear an audible bang, at least if standing outside. (The implosion energy is equivalent to something like 700kg of high explosives)

Whilst that might help to explain the delay in reporting the sub missing (presumably working out what to do), would they really have been able to hear the bang from the implosion? It was still deep when it failed so unless they had hydrophones of their own in the water I'm not 100% convinced it would have been audible to anyone on the support ship. And if it was and they knew what had happened it suggest an extremely cynical approach to pretend that they might still be alive and this was a rescue mission. The USCG (and others) would certainly not be best pleased if it turned out that they knew all along that the submarine imploded whilst letting them conduct a massive search for it.

 

[Bletchleyite]

Whilst that might help to explain the delay in reporting the sub missing (presumably working out what to do), would they really have been able to hear the bang from the implosion? It was still deep when it failed so unless they had hydrophones of their own in the water I'm not 100% convinced it would have been audible to anyone on the support ship. And if it was and they knew what had happened it suggest an extremely cynical approach to pretend that they might still be alive and this was a rescue mission. The USCG (and others) would certainly not be best pleased if it turned out that they knew all along that the submarine imploded whilst letting them conduct a massive search for it.

They'd only hear it if they had underwater listening kit on (which they may well have done) or it broke the surface. Sound doesn't really carry between air and water very well if at all.

 

[ainsworth74]

They'd only hear it if they had underwater listening kit on (which they may well have done) or it broke the surface. Sound doesn't really carry between air and water very well if at all.

Well yes that's what I was thinking. Sound travels well under water but struggles to transition between the two.

 

[156421]

Well yes that's what I was thinking. Sound travels well under water but struggles to transition between the two.

Due to the impedance mismatch at the water/air interface

 

[AlterEgo]

Did the submersible have any apparatus which would have been directly measuring bull integrity? Or would they have deduced a problem from other factors? Sounds or performance degradation perhaps?

 

[43066]

Did the submersible have any apparatus which would have been directly measuring bull integrity?

From what I’ve gleaned from various online sources, no they didn’t. However it’s difficult if not impossible to do this in real time for carbon fibre, because the mode of failure is “all or nothing”.

The most useful thing to have done would have been to periodically scan the hull to check for cracks, but they didn’t do this either, presumably due to cost…

 

[AM9]

AIUI the taper section was only exterior cladding, hiding a lot of stuff that was mounted outside the pressure hull. There was a picture somewhere showing it under test with the tail end cladding removed, I’ll try and find it…

OK, I hadn't heard that.

 

[GS250]

From what I’ve gleaned from various online sources, no they didn’t. However it’s difficult if not impossible to do this in real time for carbon fibre, because the mode of failure is “all or nothing”.

The most useful thing to have done would have been to periodically scan the hull to check for cracks, but they didn’t do this either, presumably due to cost…

Yep. With the right equipment, metal 'talks' to those in charge of it. It gives loads of indicators of its short, medium and long term health.

Our of interest was there any kind of 'black box' data recorder on board?