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Before a carbon fiber submarine was on the news as having imploded 3000m underwater and everyone in their armchair became an expert, how many people knew that a carbon fiber submarine was a bad idea? A very small handful of people. Even the CEO thought it was safe enough.
Plenty of people knew it was an untested idea, and were shocked to learn of the haphazard approach to testing.
My point was more aimed at the idea that the billionaires should have known and the implication somehow the average STW'er would have known better. That sort of hubris will get you in trouble.
It's very easy to be an expert in something niche in retrospect because it's a very easy story to tell "CEO was told the sub was dangerous but he went in it anyway". But without hindsight the story is probably more like "CEO was given a thousand pieces of information and ignored the wrong one". Remember that despite knowing all we know and more, he still decided it was safe and got in it!
The lesson learnt should be about the processes and systems that allow companies to operate safely. Tying it to the carbon hull specifically won't help you. It would be like stubbing your toe on the coffee table and resolving never to kick coffee tables again. Then walking off a cliff because what you should have learnt is the far more generic "look where you're going". Or you decide that making pressurized cylinders full of people from carbon fiber is a bad idea, so you don't. But you do mount the engines in the wrong place and compensate for it with bad software, or forget to install some door seals. But it's ok because you'd learnt the lesson not to make the tube out of carbon fiber ......
Even the CEO thought it was safe enough.
Well yes but that was because he was a fantasist caught up in the idea he knew best. Which would be fine if it was only his life being put at risk.
A cursory look shows that there was indeed a long line of experts advising against his approach and he decided to overrule them all and use the flimsy excuse of "mission specialists" as an excuse for paying customers.
Its why they avoided the classification system and decided that their own measures were sufficient. Although, in fairness, it is possible they would have been if they hadnt ignored the data the safety system was gathering.
It's very easy to be an expert in something niche in retrospect because it's a very easy story to tell "CEO was told the sub was dangerous but he went in it anyway". But without hindsight the story is probably more like "CEO was given a thousand pieces of information and ignored the wrong one". Remember that despite knowing all we know and more, he still decided it was safe and got in it!
Normally i'd agree but his chief engineer has testified that he was asked by the CEO to go in it and point blank refused telling him it was unsafe. You'd think this would give someone pause.
Remember that despite knowing all we know and more, he still decided it was safe and got in it
I think there's an implied assumption there that his judgement was sound when it very well might not have been, either through sheer arrogance and/or he had too much else riding on it NOT to get in (i.e. his company/money is at stake if he acknowledges safety failings)
My point was more aimed at the idea that ... ... somehow the average STW'er would have known better. .
Quite a number of STWers probably did know beforehand - there's plenty of engineers (I mean real engineers, not people who fit radiators in living rooms and gas boilers in cupboards) amongst this crowd, and any mechanical engineer who knows even the most basic thing about carbon fibre based composites know it's flakey and unpredictable in fatigue loading in compression.
any mechanical engineer who knows even the most basic thing about carbon fibre based composites know it's flakey and unpredictable in fatigue loading in compression.
I’ve spent most of my life in print, publishing, design and prepress, but I’ve read enough about carbon fibre over the years, and it’s applications in bike frames, aviation, motorsports and a variety of other things, and even I know it’s not an appropriate material to be constructing a deep-water submersible! Especially when it’s used to just build a tube and bond it to titanium end pieces with transparent viewing ports. Just how many ways are there where a failure is likely to happen? Honestly, I wouldn’t trust the damned thing in a marina!
any mechanical engineer who knows even the most basic thing about carbon fibre based composites know it's flakey and unpredictable in fatigue loading in compression.
so, since a bike frame is loaded in compression (and cyclically so), it's no good for that? awkward.
You can use just about any material in any application, so long as there's enough of it.
You can use just about any material in any application, so long as there's enough of it.
Err, no you most certainly can not unless your relying on "just about" doing a lot of heavy lifting in that statement
Remember that despite knowing all we know and more, he still decided it was safe and got in it!
No, as one of his [many] chief engineers pointed out, despite having an aerospace engineering degree, Stockton was pretty ignorant of some major physics principles, he didn't decide it was safe, he didn't understand why it wasn't.
You just needed to look inside it to be worried. No seats, and a Playstation controller.
You can use just about any material in any application, so long as there's enough of it.
Step aboard my artisanal sourdough submarine.
Or my concrete plane.
Deepsea Challenger
https://en.wikipedia.org/wiki/Deepsea_Challenger#Subsequent_events
Not a composite tube for fare paying passengers. The design differences are quite apparent.
No, as one of his [many] chief engineers pointed out,
Did you know that in collisions between cyclists and car drivers, the cyclist is far more likely to die if they were deemed to be at fault compared to those where the cyclists is merely injured?
It's almost like surviving gives you the ability to spin whatever narrative you like ........
d'you know that Stockton offered the job of Titan pilot to his accountant? It wasn't just Boeing that thought it was unsafe [and turned down the offer to collaborate further on the project], the man he originally bought on board to pilot the sub pointed out it was unsafe, the chief engineer pointed out it was unsafe, and refused to get in it - both complied written reports at the time, about 4 years before the last mission, even an intern in engineering (another employee he asked to be the pilot), realised that it would never be safe and resigned.
They didn't need to spin a narrative.
so, since a bike frame is loaded in compression (and cyclically so), it's no good for that? awkward.
There are a few snapped frames around. Awkward.
At the end of the day, numerous people who genuinely knew a few things about what they were doing said it was all a heap of unsafe junk, and they were ignored... You cannot stop a determined idiot.
so, since a bike frame is loaded in compression (and cyclically so), it's no good for that? awkward.
You can use just about any material in any application, so long as there's enough of it.
But aren't you compressing the bike frame in a different way to the sub?
The sub is subject to water pressure pushing around as well as along the tube from the Ti end caps - a bike frame has no external pressure trying to crush the tube (unless you clamp it ion a bike stand....), all the forces are dissipated along the frame (if that makes sense...)
Oh and you won't have a pressure differential from inside to outside on a bike frame.
P.S NOT a Mechanical or Structural Engineer, but I am an Electrical Engineer (IEng) which means I know bugger all about this stuff other than what I can (barely) remember from GSCE Physics & Materials Science on my Engineering ONC...
Hi, one of the afore-mentioned 'real' engineers here.
I'd read some stuff about this submersible before the accident, and I had my doubts back then. Specifically, the use of carbon in compression and the failure warning system. I'm not an expert in CF construction so I won't discuss that here. However, in my day job, I break things made from fibres (Not CF and normally in tension rather than compression) and I have some experience with the sounds made when you get a cascading failure of fibres. I didn't believe that acoustic monitoring would give a meaningful warning that could be acted on. Typically, the period between the warning sounds is an inverse log-time sort of relationship. For example, you might hear a crack, then another after 10 minutes, then 1 minute, then 6 seconds then under a second, then it all happens at once, and the sample is broken. I appreciate my experience is tension rather than compression but I'd need some convincing that CF will behave significantly differently in this respect.
Ultimately, I was a curious observer and assumed they'd done testing and verification that we now all know they didn't.
There are companies developing CF subs, if you read this article a person from a company called CET gives a brief explanation of their processes and why he thinks CF is a fine material to use:
<talking about material fatigue, delamination etc>
But with appropriate construction, that’s not a problem, CET asserts. To prove it, Hogoboom points to the record of his company’s products in deep-sea applications. “We’ve built vessels that we’ve cycled 200 times (to deep-sea pressures) and then brought to implosion and those fail at the same depth as new ones.”
The key is diligence in designing and testing the composite structures, Hogoboom explained. “We have a very high confidence in the strength of what’s been built,” he said. “We use engineering models, but we test to failure to validate what’s been modeled. That’s a crucial step that OceanGate has skipped," according to Hogoboom. “They never brought an exact clone to failure.”
If you're planning to step away from the well established practices of the industry, you need to spend a boat (submersible?) load of cash validating the design and manufacture. From what I've read, that part seemed to be neatly sidestepped with OceanGate.
There are a few snapped frames around. Awkward.
There are snapped frames of all materials. Your point being?
At the end of the day, numerous people who genuinely knew a few things about what they were doing said it was all a heap of unsafe junk, and they were ignored
Absolutely. But people saying "oh *I* would have known better than to go for a ride because it was CF and CF fails in compressive cycles" is just silly. Just about everything fails when undersigned or poorly built for the application, and just about everything is ok when well designed and well built for the application. The sub failed due to the CEO's attitude to testing, risk, and expert advice, and you probably had to be adequately connected to the company to have known these things prior to the failure.
Some of us are probably old enough to remember being told that aluminium frames will inevitably fail as well because they don't have any fatigue threshold or some such nonsense. I still have a Cannondale tandem dating from those days (which admittedly doesn't get much use now, but was used for daily commuting and racing and heavily loaded cycle-touring for a couple of decades).
On the subject of concrete planes, of course it's a silly idea because concrete is relatively heavy, but nevertheless:
sourdough sub was a bit of an empty net:
https://homestylealchemy.com/2020/05/11/sourdough-sub-rolls/
"I'm an armchair expert and I know that you can't build submarines out of carbon fibre"
https://www.designnews.com/industry/carbon-fiber-is-safe-for-submersibles-when-properly-applied
To save you all the trouble of clicking the link, let alone a 15 second web search (the horror!):
"Composite Energy Technologies (CET) provides carbon fiber pressure vessels to commercial and government customers such as the Office of Naval Research that have never failed in their dives to much deeper sites than Titanic, said president Chase Hogoboom in an interview with Design News."
"Chase Hogoboom" is a great name for anyone. As the CEO of a composite submersible company, it's outstanding
I've designed and approved equipment to go on actual submarines and in subsea applications and yes even GRP and CF pressure vessels that go down to great depths but they are not used safety critical application nor are they or will they ever be rated to have people inside them. Even those required a shit tonne of testing before we approved them.
I haven't got an armchair so can I be a sofa expert?
and you probably had to be adequately connected to the company to have known these things prior to the failure.
Nah you could just read their blog (plus a couple of interviews with Stockton) where they claimed "safety standards got in the way of innovation".
A bit of a red flag really and raises the question of what happens if something goes wrong.
In some cases the answer is not a lot and hence innovating is worth it but if the answer is "guaranteed death" then I would tend to go for sticking with the safety standards.
Well I'm no engineer, but there is no way I'd have gone in that device, none, zip, no chance...
I don't need any engineering knowledge to see it looked like it had been put together in a shed (from the inside at least). And call me overly cautious, but I wouldn't be betting my life on the word of the bloke who designed it that it's safe.
Even if it had all the certifications in the world, and a list of professional bodies telling me it was safe as houses, I wouldn't be inline to be one of the first to go in it.
It doesn't take hindsight to know that being one of the first people getting in that thing was a really really stupid idea. You don't need an abundance if self preservation to know that
don't need any engineering knowledge to see it looked like it had been put together in a shed (from the inside at least). And call me overly cautious, but I wouldn't be betting my life on the word of the bloke who designed it that it's safe.
There’s an OceanGate customer interviews in one of the documentaries who’s completely matter of fact about it (along the lines of “yes, it was dangerous, and anyone who thought otherwise was deluding themselves”)
If you have Netflix, the Titan documentary is well worth a watch and extremely damning to Oceangate & Stockton Rush in particular.
Plus 1. Watched it tonight. Shocking. Amongst other issues sued one of his employees for trying to whistleblow. Really worth a watch.
Registered in Bahamas and worked out of Canade to avoid USA regulation. Told an employee - any issues and he would buy a congressman. My way or the highway management style.
I’m not particularly claustrophobic, but claustrophobic enough not to even consider going in something like that! The popping noises that were passed off as carbon fibre “settling” - that was outrageous.
I’m sure actual death came quickly, but I can’t imagine the terror of the minute or two leading up to implosion.
I’m sure actual death came quickly, but I can’t imagine the terror of the minute or two leading up to implosion.
In an earlier documentary or news report, I remember someone mentioning that the duration of the implosion from start to finish would me measured in milliseconds, just winking out of existence effectively (so the victims would known or experienced nothing). Judging though by the recordings of carbon breaking accelerating with depth during successful dives, I'd also expect there to have been plenty of forewarning of imminent failure which must of been terrifying.
Another of those 'interesting facts' was that if, at any time, the Titan had sprung a leak, the water pressure was such that the jet could have cut those inside in half.
Watched this and the BBC one as well.
Regardless of materials, what came out of both documentaries was a dominant CEO and a hardcore say yes to the boss and FIFO culture (fit on or leave). This is dangerous in terms of operations and finance in any business let alone a safety critical one and regularly a precursor to failure. I see variations on this as a common theme professionally when looking at business failures (sometimes it's more than one individual at top level but usually less than three when you see it).
For balance we do have to be mindful that he's not here to present his side of the story and what makes good TV and social content. I'm not sure there's anything that might change my view but for completeness.
Without driven innovators we do have a risk of stagnation of development but that can come at the expense of a failure to recognise when it just doesn't work / isn't going to work and to blame others / the establishment. Holding the innovative mindset, the need to stop when it just doesn't work and the consequences of getting it wrong in balance is difficult. From what I've seen here my feeling is they were so far past that line that it was over the horizon.
Ive not seen the programs yet.
Full disclosure, I'm an engineer (whatever that means these days) and i love looking at innovation and those people that push the boundaries. There is a very fine line however between pushing the boundaries and recklessness. In this case (IMO, ive not seen anything bar whats on the news) the CEO had a hire and fire them mentality. This does not work well with engineers. They tried new things but instead of testing them assumed they would work. Theres a proof of concept and then taking this out to a product you have to prove thats its not a 1 of 1 pass / fail scenario. They completely failed to do this imo. Previous research shows that people had failed at this type of thing before and while you can engineer your way around some of the failures you also need to test and understand why they happened. I dont see how this has happened. Although as a paying customer you would totally expect it to have been done.
The question i have is while this is clearly the overall fault of management how far down the chain does it go? at which point when an engineer says this isnt right and is overruled or if the engineer says i thought it was someone elses job (as i believe the lead engineer has done) are these people going to get hauled over the coals for peoples deaths?
This is clearly a smoking gun, there is undeniable proof that corners have been cut and poor decisions have been made. Who is responsible?
In an earlier documentary or news report, I remember someone mentioning that the duration of the implosion from start to finish would me measured in milliseconds, just winking out of existence effectively (so the victims would known or experienced nothing)
Speed of implosion was about 1mS.
Human instinctive reaction time is about 25mS (says Dr Google).
If you have to process and react then that time is more like 250mS.
I watched the Netflix one last night. As alluded to above, we do only have one side of the story now but that footage with the audio of the hull popping and banging while descending was horrendous, now knowing what happened.
And being ghoulish, for which I apologise, those tests of the scale hull did show catastrophic failure, but the entire hull did not just crumple in on itself and obliterate to nothing, failure still seemed to be at a defined point of the structure with some shape remaining intact. I’m assuming that as the test was in a vessel which then equalised once it had failed, this would be different to being fully immersed in the acting pressure, as in 4000m down?
Potentially slightly different failure outcomes exist. It still failed.
Not certain how applicable a scale model was. Lots of possible variance between a small one and a big one and to put it mildly, I'm not certain the oceangate outfit had any of that under control, let alone ensuring consistent and sufficient quality of build of either small or large.
I don't need any engineering knowledge to see it looked like it had been put together in a shed (from the inside at least). And call me overly cautious, but I wouldn't be betting my life on the word of the bloke who designed it that it's safe.
Yep, needs to be more https://tritonsubs.com/subs/gullwing/
With er actual seats and a bigger window to actually see stuff, made of Acrylic so pretty funky on materials.
(but tbh I’m not that interested in having an ‘experience’ to visit the titanic , probably have more enjoyment in watching a documentary of it at an imax with a big box of popcorn.)
Not sure I want to watch the documentary since we know the ending.
Acrylic so pretty funky on materials.
I thought acrylic was pretty well used in submersibles, and a (more or less) sphere is the ideal shape for a pressure hull?
Acrylic so pretty funky on materials.
I thought acrylic was pretty well used in submersibles, and a (more or less) sphere is the ideal shape for a pressure hull?
Yes and even better would be to cut that sphere in half, and slap a carbon fibre body in the middle. You could fit like 4 billionaire passengers mission specialists in then.
Yep, needs to be more
What this is the Titan! You daft ****, I definitely said book us on the Trito...................*
* transmission ends here, no further messages
Sorry said all that further up.