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Forgive me if somebody else has already posted about this. What’s going on with that submarine that tried to tour the titanic wreckage?
Is it a stupid idea in the first place? Is there any chance they’ll be rescued?
I’ve been fascinated by the fact that even the richest among us are only surviving because Mother Earth decided not to crush them today. Seems like these people just had their luck run out, and maybe made a really stupid decision?
The more I read about it, the more idiotic it seems.
First, using the Titanic site as a tourist destination seems a little tacky. It's a gravesite, after all. But hey, Modern Times, make money out of dead men's bones, why not?
Then the details of "billionaire paid to go on trip" and the cost, and the details that they used a repurposed game controller to drive the thing.
Now, maybe that's actually feasible, but somehow it doesn't give me a good impression of the entire operation.
I hope the people are rescued, I don't want any deaths, but I also hope this stops this kind of ghoulish monetisation.
This was an excellent decision. Using the two millionth product of some mass-manufactured part, under shirtsleeve conditions like those where the part has already been heavily used, is almost always going to be more reliable than using the first or second product of some custom design.
The stories from David Lochridge and David Pogue, on the other hand, suggest many other much, much less excellent decisions. Normalization-of-deviance is a slippery slope.
I dunno, were I in a tin can going to crush depth, I think I'd prefer if they steered the death trap with something a bit more advanced than "Oh crap, the wifi's dropped out, gimme a sec" (not even a tin can, they were using carbon fibre or something?)
Aside from all that, the stepson of the British billionaire (queried) is reaching Hunter Biden levels of "dude, what the hell?" He has no right to be surprised when the will is read and he is cut off with a shilling, since he can't even bring himself to pretend to care about what is going on. Instead of being at home with his mother, sister and half-brothers in some kind of show of family unity, he's heading off to concerts and messaging Only Fans and the like.
It's /r/Drama but honestly, this is indeed tabloid territory and the best place for it. How stupid is this guy? Has he no self-awareness? "Oh, (Step)Dad is probably dying horribly right this minute, I guess Mom and my brothers will be really upset about that - well, time for me to head out and have fun! All in the name of self-care!"
Titanium end-caps, carbon-fibre cylinder. Carbon fibre can be much stronger than steel, much less tin, and they'd successfully made several dives that deep already ... but composites are harder to engineer with than metals, and the short history of composites for these ultra-deep dives is worrying. Compare:
"The design of the Cyclops 2 hull, says Spencer, is based in large part on the strategy applied to Fossett’s DeepFlight Challenger" (Spencer Composites was OceanGate's original choice for the hull manufacture, though they say it wasn't their hull in this dive, I can't seem to find what later manufacturer was chosen)
to:
"Based on testing at high pressure, the DeepFlight Challenger was determined to be suitable only for a single dive, not the repeated uses that had been planned ..."
And in 2020 the Titan "had to be completely rebuilt after tests showed signs of ‘cyclic fatigue’" ... just from testing? They've had successful trips since, but not nearly enough that I'd be confident they've figured out fatigue.
I've probably watched too many episodes of "Voyage to the Bottom of the Sea" where getting to crush depth is something you don't want to happen, and that high-tech super-sub was not made out of carbon fibre composites.
God rest the dead, but this all does seem like an avoidable tragedy.
"Crush depth" is pretty much defined as "the depth where it's something you don't want to happen". "Design depth", still well below "operating depth", is where you planned for crush depth to be, and most of the time it's not quite as deep, because surely you built your design with tolerances all on the safe side rather than the quick+cheap side ... but based on everything reported up to and including the debris discovery, that doesn't seem to have been the case this time. RIP. At least they went instantly.
Yeah, my jaw dropped when I went to the website and it was cheerily "our prototype predecessor model went to 500m. This time we're heading for 4,000m."
I mean that is some scaling-up without intermediate steps in between! But God rest them all, they paid the price. Including the CEO, so it's whoever is left behind in the firm is going to be carrying the can for this one.
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As I recall James Cameron's (steel) sub was designed to shrink a few inches when it got to the bottom of the Mariana Trench -- granted this is something like three times deeper than the Titanic wreckage, but it sounds like a really bad environment for carbon fibre fatigue.
The only thing inaccurate about the scene in Down Periscope where the guy stretches a string across the engine room, and it sags as they dive? He states that you wouldn't see it on a nuclear sub, which is wrong. I'm pretty sure every submarine is designed to compress under water pressure, and combat subs don't dive nearly as deep as exploratory subs.
Yeah -- CF is bad in compression generally and (in my non-materials engineer opinion) probably especially bad when it's evenly compressed around the whole surface. (and then decompressed whenever it surfaces, of course)
I could imagine ways to overcome this (laying up the fibre under pressure?) but it seems very process dependent -- "Trust in Steel" OTOH is time-honoured.
Is there even any downside to using a giant steel ball for a submarine pressure hull? You're not paying to shoot it into space, you literally just want it to sink. I know the Soviets used titanium, but they did a lot of crazy stuff.
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