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yabones

What can we learn from this? Don't go in pressure vessels; don't go in confined spaces.

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What can we learn?

Just because the CEO is on the firing line with you, doesn't make him right, just overly confident.

DO hire "50 year old" people with experience, not just kids from university.

Don't build your pressure vessel out of materials which are hard to monitor for wear and fatigue.

Listen to your experienced employees when they tell you that you've built a death-trap.

If you have $250,000 to spend on a short vacation, maybe pick one with better odds of getting home.

and finally...

...The media will always stretch out the agony of these stories for as long as it generates clicks.

> The media will always stretch out the agony of these stories for as long as it generates clicks

Off topic random thought: the increase in mass shootings and their normalization in the US media means those stories don't get as many clicks as they used to.

I suppose any given stimulus becomes routine after enough exposure, so yes I guess to reach the same audience a more novel sort of shock is required.

That's a gross oversimplification. There have been multiple vessels that have successfully explored the sea floor.

What set them apart was a distinct lack of SV VC-level "move fast and break things" bullshit and utter reckless disregard for safety.

Was there a legitimate reason to take that risk?

What I don’t get is why there is no beacon on this device. That should be law. This search is costing tens of millions and without a beacon they never had a chance. From what I understand of the construction and debris there is a very low order of probability they will be recovered alive. Even if they are found conserving air they can’t extract the module in time. It takes at least 24 hours to build the necessary rig. They knew this going in, so why search at all? I mean they’re lost at sea no matter how you slice it. Apparently while touring at the wreck of others lost at sea which isn’t a rational gamble to risk your life over. I mean they bolted the door from the outside because the pressure was so high surely that was a clue. And if they did survive the impact, five people panicking without air in that confined space can’t have been pretty. What a mess

I mean I think the bigger take away is to not cut corners when operating with such a small margin of error as DSVs. Safe deep-sea exploration is possible, and has been for a long time, in manners such as the DSV Alvin, DSV Limiting Factor, etc., etc. The manner in which the Titan was made and tested indicated a severe lack of safety oversight from OceanGate. As unfortunate as this is, there's the saying that rules are written in blood, and this is yet another case. I doubt there will be many such cavalier attempts at deep sea exploration and tourism in the future as a result, for the better.

There are exactly two lessons to learn from this:

- safety regulations, especially for high-risk low-margin-of-error endeavours are there for a reason, and we've already learned all these lessons the hard way

- the probability of any given billionaire being dumb as rocks is close to 1

> What can we learn from this?

Probably the same lesson we learned last time an ocean vessel named after a Titan went missing in that vicinity

Carbon fiber composites are a wet noodle in compression. They're supposed to be used under tension.

Hopefully this is the last time anyone tries to make a negative pressure vessel out of carbon fiber.

I think it’s more along the lines of “learn from the experiences of others”. It’s my understanding that there are quite a lot of very smart people who have spent decades figuring out how to build these things relatively safely. This company decided to ignore the existing knowledge base entirely because what the industry had learned was expensive and inconvenient for a fledgling tourist company.

What’s that analogy about taking down a fence without understanding why someone put it up in the first place?

Chesterton's Fence.

There are a number of reasons why it might have failed, fatigue, deviation from process/protocol but pressure vessels are well understood and not the problem here.

Are carbon-fiber pressure vessels well understood?

I get that there's a lot of armchair quarterbacking from internet material experts here, but this does seem to be an outlier with this particular submarine.

They're well-understood to not be what you want to build a high-pressure submarine out of.

They can take the pressure. But they're incredibly expensive to check for defects, and the result of a defect is "sub-second catastrophic failure" instead of any warning of imminent structural degradation.

I think their behaviour under pressure is well understood. Not a popular choice for subs, though.

The issue seems to be hull integrity, namely being able to inspect the hull before it's failing in order to detect issues without risking anyone's life. The only thing they could do with a carbon fiber hill is use an acoustic hull monitoring that only told you that the hull was in the process of failing - so potentially getting no real warning at all. It does you no good finding out your hull is going to implode in 10 seconds when it will take you an hour to get to safety. This is what the ex-OG employee got fired over because he made a stink about how the carbon fiber hull was unsafe for this reason.

The main cause for the failure seems to be "sheer f-ing hubris," but those could certainly be contributing factors.

Being charitable to those lost, I'm reminded that explorers are courageous and always have some measure of hubris.

A commercial airplane is a pressure vessel. So is the hot water heater in your house, the espresso machine on your countertop, on and on.

I'm going to keep flying, but just not get on any experimental, uncertified craft of any kind, airplanes, submarines, etc.

Your comment is akin to saying well, that sub had bolts on it so I'm not going to trust bolts from now on. Really, it's just that the bolt was used incorrectly by a person with less than virtuous intentions.

Do airplanes count?

Eh, the pressure gradient is a lot less dramatic in a jet vs. under 3500m of water.

As Futurama famously said, airplanes are rated for a pressure differential somewhere between zero and 0.7 atmospheres. With the positive pressure being inside the plane.

This submersible needed to survive a differential of ~350 atmospheres. With the positive pressure being outside the craft.

Clip for anybody who doesn't know the Futurama reference https://youtu.be/O4RLOo6bchU

Also the airplane shell has to endure tension forces, as inside has greater pressure than outside, whereas the sub has to endure pressure. Some materials work well under tension but not pressure and vice-versa.

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