New evidence strongly suggests that OceanGate’s submersible, which imploded and killed all passengers on its way to the Titanic wreck, was unfit for the journey. The CEO, Stockton Rush, bought discounted carbon fiber past its shelf life from Boeing, which experts say is a terrible choice for a deep-sea vessel. This likely played a role in the submersible’s tragic demise.
That guy was a backyard inventor and charlatan, like those 19th century backyard aircraft inventors. It’s one thing to take yourself out of the gene pool through your own recklessness, it’s another to take others with you.
Rush bypassed over a hundred years of engineering lessons learned the hard way with the rationale it stifles innovation. He even fired and sued one of his own employees for calling him out on it. The sub had zero certifications and then he lied to customers about it saying his designs were approved by NASA and Boeing who never even heard of the guy.
Aside from the lack of safety engineering and lack of proper fail-safes in his design, there’s a reason engineers don’t use carbon fiber composites in subs. They have a tendency to delaminate. When used in aircraft, composites have to be examined and certified at a regular service interval with special inspection equipment.
I think that sub was an accident waiting to happen from day one. The hull probably failed due to inspection negligence and a failure to detect delamination. That’s even if the hull could have been rated properly for 4km. If it wasn’t the hull, it would been one of the other jury-rigged systems.
I can’t believe people smart enough to acquire the wealth for that excursion weren’t smart enough to check out the qualifications of the company hosting it. I think it was plainly obvious just looking at the sub yourself. A navigation system that consists of a consumer laptop PC and Logitech gaming controller should have been a dead giveaway.
I can’t believe people smart enough to acquire the wealth for that excursion
You do not need to be smart to acquire wealth.
Of the people in the sub, I am confident that 4/5 of them were born into wealth, and I can’t really find any information on the other one.
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The Dawoods (father and son) were only wealthy because their father/grandfather was wealthy.
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Stockton Rush was also born into wealth, his family made their money from oil and shipping.
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Can’t find a lot of information about Hamish Harding, but he was flying aeroplanes at 13 and went to a prestigious private school called The King’s School, so it’s safe to say he was also born into considerable wealth.
The 5th guy worked for the company that owned the salvage rights to the Titanic, was a professional diver, and was considered an expert on the Titanic, and he’d been on a lot of dives before to recover artifacts and map the wreck.
He more than anyone should have known this was the crappiest sub he’d ever been on, but he was seemingly obsessed. I can imagine he was invited and didn’t pay for a slot.
The Titanic expert diver seemed to act as a tour guide, based on video of a previous excursion.
Initially, I thought Stockton Rush couldn’t be a total moron because he had a degree in aerospace engineering from Princeton, but having followed the college admissions scandal, we know what those degrees are actually worth. Crap.
The college admissions scandal was for people who didn’t have enough money to donate for an entrance ticket. If you’re rich rich you just donate a bunch of money and your kid gets in, no scandal necessary
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I don’t get why carbon fiber was used in the first place. The composite material is known for its great tensile strength: tensile as in tension, not compression. Carbon fiber is actually also known for being lousy at handling crushing (compressive) loads. If you crush carbon fiber, it’ll fail shortly after.
Going under water would place the vessel under compressive loads, which at a quick glance would be the wrong type of loads for carbon fiber. That’s my initial take on it, however I haven’t spent any real time trying to engineer one.
First, he was an aerospace guy and several things he’s said make me think he was sort of chauvinistic about deep sea exploration in general, stuff like “It’s perfectly fine. Having all these certifications for airplanes is one thing, but the carbon fiber was perfectly sound.”
Second, his business model, taking four people down with him in something other than Cameronesque claustrophia, and doing so without the cost of owning a proper launch vessel, instead renting any ship that could hold and then monitor his launch sled, meant it was critical he make something big and light, by deep sea submersible standards, that was at least nominally expected to handle the load. Shit, I guess in some sense, he did, since it went down and back two or three times or whatever. At the absolute best, though, he’d invented a disposable sub, and he clearly didn’t worry about that limitation any more than the rest.
he was an aerospace guy
— How l’any atmospheres can the ship withstand!?
— Well, it’s a spaceship, so I’d say anywhere between zero and one…Wait right here! …toilet flushing sounds in background…
Fiber composites are complex. Carbon fibers can be made to withstand compressive loads in that you make composites with the CF and other materials. Even so carbon fibers are about half as strong in compression as tension. Even so, carbon fiber might have a specific strength of around 3000 kN-m/kg, steels might be around 63 kN-m/kg. So it’s not as simple as “carbon fiber isn’t as good in compression as tension, never use it in compression.” A lot of current research in aerospace is to produce better manufacturing methods and resins for carbon fibers to phase out aluminum and steel parts. Mostly in tension yes, but compression too, all parts without preloading generally are some degree in compression during their stress lives.
Should he have bought expired carbon fiber for a submarine? No. Is carbon fiber completely absurd in submarine usage? I don’t imagine so. Though steel is plenty fine for a submarine, normally the hard part is the sinking by design, not the floating, so weight savings aren’t super important.
I have absolutely zero knowledge on deep sea submersibles but every bit of reporting I’ve read or listened to over the past week has said that carbon fiber is a very poor choice for a deep sea vehicle. Given its propensity to eventually delaminate, it is much more likely to fail over repeated uses than titanium or the other materials the industry uses (I’ve primarily heard comparisons to titanium).
Delamination is just carbon fiber composites main mode of failure. As long as the material you use is rated for its stress life it’s fine. Buying expired material means the resin was decomposing, making the carbon fiber composite more prone to failure.
All materials eventually fail, some have endurance limits with infinite stress lives, like most steels. Some don’t, like aluminum. Without knowing the details of their design there’s not an easy way to say whether carbon fiber was even a bad choice at all. But buying expired carbon fiber absolutely is a bad idea for anything critical.
The stress life curves for carbon fibers vary a lot, they certainly won’t be as nice or long lasting as most metal alternatives, but that just means more replacement or maintenance, something a luxury submarine doesn’t necessarily care about as much.
learned the hard way
He learned nothing, he is dead. Hopefully others will learn from that.
“Safety regulations are written in blood”
That’s putting it harshly.
Would be interesting so see a statistic on deep water sub excursions versus fatalities. Probably somewhere between astronauts and WWII bomber crews.
There is little regulation for deep sea subs since they operate in international waters out of jurisdiction. You can pretty much do whatever the hell you want out there. If someone manufactures within jurisdiction, regulations may apply. Though they would be easy to circumvent.
Definitely good safety and engineering practice is written in blood, but regulations are not always enforceable.
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Some record breakers don’t bother but those are always manned by one person as a private venture and still follow those rules as guidelines. They just don’t bother with the formality. The challenger deep wasn’t for example. No one balks at that because the people involved knew what they were doing and used pretty sound and tested engineering.
Protip: you can set dates on a Google search to avoid recent news when trying to look up historical information.
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Can you set times to ignore new articles? I thought you can only ignore old articles.
You can do a custom date range including an end date.
Huh, you are right. Never knew this. Thanks! That’s gonna be useful.
Problem with the norms is it’s harder to fit five people in a proper sub than a cheap sub. He wanted to “innovate” (cut corners for profit and fame) not do things the right way
Honestly, the most surprising thing is that they managed 6 successful dives to titanic before it failed.
And that they convinced multiple billionaires, who are generally assumed to be smarter and better educated than the rest of us, to step aboard that blatantly-unseaworthy deathtrap.
Guess what, billionaires aren’t smarter than everyone else. Usually it’s just existing wealth, luck and a lack of morals that gets them there.
The system is rigged to make it much much easier to make money if you already have money.
There are a lot of different types of characteristics that get described as ‘smart.’ Risk aversion is often categorized as ‘smart,’ as in “I’m too smart to do something that risky,” but that is definitely not something billionaires are known for - you can’t get that much money without big risky bets paying off.
Rich people don’t really seem to be smart so much as they just have a sort of rat-like cunning that confers high performance at screwing people and stealing shit.
On the contrary, I’ve long been of the opinion that anyone can claim their slice of the American Dream, just as long as they aren’t too picky about who they carve it out of. There doesn’t even need to be risk, per se, just some ambition, enough intelligence to know the limits of you can get away with, and a complete lack of shame.
Lack of shame doesn’t do you any good financially if you aren’t using it to take social risks that people with shame wouldn’t
But that’s my point. The only real risk is that somebody with an overgrown sense of morality might think badly of you. As long as you don’t cross the line of hurting someone who matters (in the sense of being rich or powerful) you can just reenact that meme of Jason Statham wiping his tears with wads of cash, and get on with the exploitation.
Stress fatigue and fractures doesn’t show itself after one dive without completely tearing down the craft and inspecting components - and this was probably the deepest dive they’ve been on.
pressure increases on a log scale the deeper you go, so you need to account for that, evidently, they did not account for it, and they also failed to understand requirements for regular teardowns and inspections of prototypes.
Honestly I don’t find it surprising at all.
There are multiple times where people have died due to fractures as a stress fatigue in different areas.
I remember a story about the crash of United Airlines flight 232, in where a DC-10 suffering an undetected stress fracture after many flights finally broke an engine to the point of it severing out all hydraulic lines to the control surfaces - they had to try and land the plane via throttle. It’s actually a very interesting story if you want to look it up - they even made a movie for it.
The issue here is the number of dives it took before something failed catastrophicly - you usually engineer it to withstand the stress for X number of dives - 6 dives are far too few and and it is indicative of poor design and poor maintenance. - compare UA232 where it only happened after multiple years and 200+flights before it finally failed catastrophicly.
pressure increases on a log scale the deeper you go
Pressure increases linearly in water because it’s not compressible. You’re probably thinking about the exponential increase in air
Whoops, I guess I made a mistake. Ah well.
I can’t believe people smart enough to acquire the wealth for that excursion weren’t smart enough to check out the qualifications of the company hosting it.
I have met several gazillionaires. Some are quite smart, some not so much - but every one of them thinks that they’re smarter and more capable than they are
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Being smart is a strict non-requirement for acquireing wealth. You really don’t need to be smart to get wealthy. You need to be unscrupulous enough to rip off others. You need to be happy to gamble a lot of money on risky ventures and you need to be lucky enough that the risky ventures work out and don’t blow up.
And inheriting lots of money and connections usually helps as well.
Incidentally, this seems to fit the bill for someone who’d pay a quarter million to poop in front of 4 people on the way to an assisted suicide where in the best case you can watch a video feed of the Titanic.
I wonder if there was some level of wealthy person peer pressure involved. Rich people aren’t that stupid (I’m being generous here and looking for reasons) and maybe there would be some backlash in not going ahead with things, even if red flags were found. It’s not like those flags were hard to see, apparently anyone in the submersible field knew this guy and what he was doing wrong.
I think most billionaires have a bit of their brain set to believe in themselves rather more than is warranted. It’s great for making money, but maybe not something you want to put your life on the line over.
I think it scratches a similar itch as most techbros: “if I can solve this hard problem, all problems are easy!” It’s a mentality I see constantly, especially on the orange site.
Problem: exists for decades and has not been solved by experts with tons of funding in all that time.
Redditor with zero knowledge or context: Why don’t they just do X, Y, Z? It’s so easy 😏
In this case, the problem was solved over 60 years ago. This billionaire decided to reject the tried and tested solution and came up with their own.
I like asking the “why don’t they…” question as a genuine question because it’s a great way to learn a lot in a short time
It’s worse than that. They’re narcissistic and think they have the answer to every problem. I worked for a boss like this who had Aspergers syndrome (undiagnosed, but clear case)
He literally had bumper stickers made up with “[his name] is the answer” - he wasn’t joking. If there ever was a problem he would immediately solve the problem in his mind, and that was the way we MUST do it. He would not accept rationalization as to why that might be a bad idea. I learned real fast not to tell him we had a problem… until I already had a proposal, who was involved, and costs involved to fix the problem before he had a chance to solve the problem himself.
As someone on the autism spectrum myself, we’re usually fairly open to whatever the facts are whether that disproves us or not. There’s a lot of overlap at times between narcissistic traits and autism, are you sure he just wasn’t a narcissist? I say that because refusing to accept the rationalization of what may be a bad idea just sounds dumb. (The bumper stickers made stand out to me too).
Alternatively he was just someone with autism who is narcissistic and dumb, who refused to accept any new information that countered what he had settled on.
I worked with him for 13 years, I wasn’t the only one who saw the classic traits
- Difficulty in reading other’s feelings
- Aggressive behavior (childishly would throw his keyboard or trashcan across the room during meetings when unhappy with the answers he got)
- Clumsy muscle coordination
- Inability to perceive gestures by coworkers
- Lack of social awareness
The list goes on and on. But needless to say he refused to accept he might have been on the spectrum or get tested despite suggestions by fellow staff members who also dealt with his irrational outbursts on a daily basis
I think is just that it depends on the person, like some ppl might be less open than others bc thats just how they are whether or not they were ND. Maybe thats just how hise personality is or how his traits manifest
especially on the orange site.
Hacker News can be so engaging, but then you go to the comments and it’s so enraging.
There was a study done on this kind of mentality. Researches invited pairs of players and before each game flipped a coin to designate one player rich and the other poor. The rich player was then given more money and an easier set of rules. At the end of the game they interviewed the player that inevitably won, and in all cases the players reported that they won because of key decisions they made while playing. Not one mentioned they got lucky with the coin flip.
Summary and interview with a researcher: https://www.marketplace.org/2021/01/19/why-rich-people-tend-think-they-deserve-their-money/amp/
Study (pdf): https://studenttheses.universiteitleiden.nl/access/item%3A2661526/view
I’m surprised this isn’t a named sort of cognitive bias. I think there’s a related thing where we humans tend to cite external causes outside our control when we are unfortunate or make mistakes, and we tend to cite our own virtues when we are fortunate and successful.
I think this would be considered Self-serving bias.
but maybe not something you want to put your life on the line over.
To be fair, their hubris usually only kills poor people so, progress?
Agreed. You need a bit or a lot of narcissism.
It’s implicit bias.
Our forefathers has orchestrated a world of scarcity. They raised us telling us how America is in overwheming, inescapable debt (even though that debt is a useful byproduct of our financial excess and has no deleterious effects on our future) and how everything will always cost something and how we are fools for ever thinking anything could be better than this, right?
After living through that, if you become a billionaire you must feel like you are by and large exempted from those rules.
I had a good bit of thought about this too… This kind of mindset should never be allowed in customer-facing fields in the first place (cough cough all the social media privacy hellhole we are in today…), let alone ones that risk human lives tbh.
A bit of the ‘it wont happen to me’ mindset.
the screen was mounted by screws into the carbon fiber. fuckin’ what!?
what’s wrong?
Don’t you drill holes into the fibers of the carbon-fiber therefore rupturing the fibers and negating all the tensile strength of the material?
are you stupid? everybody does it…
The interesting thing is he really seemed to believe he knows better than all the experts.
There are reasons why ships and planes are all highly regulated. Its called physics.
I’m so conflicted on this. On the one hand he seems like a giant asshole that saves on safety to make a few more bucks but on the other hand he trusted his system completely and died with it. So not really greedy asshole but stupid entrepreneur who didn’t realize how wrong he was?
Both. The drive to be a cheap pos caused him to believe he knew more than he did.
It’s one thing if he died alone and another when he took other 4 people with him. I would still chalk it up to greedy asshole, because he cheap out things that would’ve saved the four people.
A greedy asshole who thought himself a genius?
The word is arrogant.
The fact he started charging after several warnings from Industry players does raise the asshole angle
I guess society needs people like him that make crazy things. Science itself is pretty much like this, trying out stuff and be creative. People often made inventions while other people were telling them that it would be impossible to do so.
However, I think where he actually behaved really like an asshole was taking people with him who he made believe to be in a safe vessel. He could have made a disclaimer saying something like “this is an experimental vessel, I’m not sure if it will hold up and people have warned me. I still want to take the risk and you can come, too, if you are willing to take the same risk.”
Taking risks for the sake of innovation, fine, I guess it has to be done to move forward. However, building a submersible that can go to these depths is nothing new. Been there, done that, basically. To throw all lessons learnt with previous vehicles out with the garbage is just monumentally stupid.
Engineers and scientists do try to do and make crazy things but they try to do it safely, and doing it safely costs money which he didn’t want to spend.
I guess the most positive spin is that he risked and gave his life to try new things which can progress things more quickly, but he didn’t just risk his own life, he risked the passengers which is unforgivable. If he were doing it solo to not endanger others then I could respect that.
I agree with you. It kind of itches me that he was just so ignorant of already established knowledge. But then, this is exactly the point where we fall blind to alternative solutions because we are limited by our prior established rules. So I didn’t want to judge, but yes he seemed to be very ignorant.
I would respect it for some team doing something as risky, that’s what I wanted to express. That he took paying customers was unethical imo.
Thing is, as James Cameron pointed out in his interviews, this is not a cutting-edge field. The science of submersibles is well explored and the technologies are mature. Engineers know exactly how to construct a safe submersible to go as deep as you want. There are companies like this that make and sell these submersibles.
This guy was not doing research or experimentation. He was trying to cut costs because he probably couldn’t afford a proper submersible under his business model and still make a profit. The only reason for using unconventional materials - materials that are well known to be unsuitable for this purpose - was that he thought he could do it more cheaply if he didn’t go through safety certification or buy a sub that had already been certified.
Science itself is pretty much like this, trying out stuff and be creative.
absolutely not. he wasn’t some creative pioneer exploring the unknown. he was a moron that operated in the environment that is known and explored in great detail and just decided to cut on the costs by ignoring all the best practices.
I’d bet they signed release forms which said pretty much exactly that.
A greedy asshole who thought himself a genius?
Physics is just a concept for lame traditional non-disruptors, with the power of magical thinking and endless money we can make hyperloop work!
It’s almost as if someone built a giant ship they were incapable of operating
It’s shocking how many corners one is willing to cut to save money even if it means lives.
Greed. Always greed.
Because this CEO bet his life on his ideas, this would be more about hubris than greed. If it were just greed, he would have bet someone else’s life.
He was trying to bet others lives too- offering greatly discounted rates for a trip and outright lying about the safety to try and convince others.
reading this almost feels like it was merely an effort to perform the most expensive suicide ever.
But then again, it could also seems to have been stupidity and a failure to listen to experts.
Man seems to have been unable to get his head out his own ass and was basically hearing every issue and going “this is fine”
Seems like in any case, he deserves a Darwin award, just sucks that other people went down with him.
In this case, not suicide, but stupidity. You read the things this Stockton man was saying around and you notice it was a case of not knowing what he was dealing with. He also bragged that the certifications and security inspections were actually a burden to advance technology.
“If we make the sub less safe that will be better” -Rush Stockton (paraphrased)
my brother in christ safety IS advancement. the safer the sub the deeper it can go (kinda), which could allow room to introduce other things into the sub like a fancier cabin.
I’m beginning to suspect this Stockton man had a case of amooth brain…
Welcome to many many many CEOs/entrepreneurs/MBAs. I’m surprised it doesn’t happen more often, then again it’s relatively rare to be in this kind of business and your own passenger
You can’t get sued by your customers if you’re dead *taps head
It could have been fresh from the factory and would have had the same result It was an improper application of the material to save on the more expensive titanium Same with the acrylic viewport, while not the best material it’s the design that was non-standard Quartz would have been better but more expensive Not the time to cheap out on materials, design, nor experience when lives are on the line
Fresh from the factory might have got away with it, they tried to reuse a vessel that was barely useable for 1 journey and had known material flaws that would have limited the number of pressurisation cycles the craft could have taken.
From my limited experience with laying up carbon fiber, I know there’s the raw carbon fiber cloth and there’s liquid resin that you spread into the cloth. It’s also very common to see carbon fiber cloth that is “pre-impregnated” - the resin is already applied to the cloth. Everyone calls this “pre-preg”.
So I’ve seen a lot of folks online scratching their heads about “how can carbon expire?” or “my carbon fiber (bike/boat/etc.) is N-years old, is it expired?” but I think the most likely thing to expire is the resin. Once the resin is cured it is much more stable.
Any materials folks or structures engineers who want step in and correct me, please do.
Also most bikes aren’t under enough pressure to cause them to implode
Not with that attitude.
Lmao
Relevant IT Crowd: https://www.youtube.com/watch?v=elrV-oHeSjE
STRESS
Actually CF road bikes only have a safe lifespan of about 10 years - https://icancycling.com/blogs/articles/lifespan-of-road-bike-frame
<insert yo mama joke here>
Different loads, different failures, but still a valid safety concern.
I would not want my bike frame or fork to be made with expired resin. But the age of the bike after the CF is cured is a different matter.
So I’ve seen a lot of folks online scratching their heads about “how can carbon expire?” or “my carbon fiber (bike/boat/etc.) is N-years old, is it expired?” but I think the most likely thing to expire is the resin.
Well it would have an expiry if purchased from Boeing. All materials used in aircraft have stringent performance requirements. Resin is a plastic and like all plastics it degrades over time. It can lose strength and fail to meet materials ratings. Now if you wanted to make something like a regular boat hull out of the stuff it would probably last a lifetime, but if you want to make something like an airplane wing, that’s a different story.
Anyway carbon fiber composite is stronger and lighter than steel, but the wonderful thing about metals is they can have good properties for supporting all kinds of loads. But even then you have to inspect for fatigue on a regular basis when loads cycle repeatedly. Carbon fiber doesn’t do as well with that.
I agree with all of that. My intuition is that prior to curing, the polymers are less stable and may change in unpredictable ways depending on subtleties in the storage environment and handling. After curing, the polymers are much more stable and durable.
Metals definitely are more forgiving, and we have better tools for testing, especially non-destructive testing. Whether the CF flaws are due to fatigue or workmanship, it’s easy to miss them in inspection.
I’m also curious what the sub designers saw as the advantage of CF for this application. Is light weight really all that advantageous for a submersible? Generally no one chooses CF if they are prioritizing cost.
I don’t see where it fits as a good solution either. Typically it’s used where weight is the main consideration, such as in aircraft. CF is more expensive, has higher maintenance cost, and more difficult to produce than metal. Was it more about doing something different than doing it better? Well the tried an true method for deep sea submarines is a titanium sphere and that’s quite expensive so it probably was a lot cheaper.
In his scenario weight was a factor.
They were trying to get the sub to be as light as possible so it could be operated from nearly any vessel. The goal was to have the sub and a launch sled that could be launched and recovered aboard a rented ship. This was all to save money; they didn’t want to have to purchase and outfit a special purpose support vessel.
I think the design was flawed from the start, proper stress testing would have revealed it. From what I understand they basically sent it down a few times and said all good, we’re done.
The sub did have titanium front and rear bulkheads. If their goal was to make it cheap and light, they might have done better hatching together a train of CF spheres. A cylinder is not strong enough.
Though to be fair, even the best design with the most rigorous testing can fail catastrophically. If that weren’t the case space flight would carry no risk. And space is easier to deal with than the pressure at 4km ocean depth. Still that doesn’t change my opinion of Rush, he was a hack.
Even worse, in the only third party testing that was performed, by the University of Washington, they rated the original iteration of the Titan only up to 9800 ft. As far as I can tell, Oceangate never redesigned the sub after that, and still decided to take people to 13,000 ft.
Also, given that Rush would brag about how cheap the original hull was, I doubt they fully replaced it when they noticed cyclic fatigue in the sub later. To me it looks like they did some kind of shoddy repair. And that’s the Titan everyone ended up with.
Also, given that Rush would brag about how cheap the original hull was
I’ve seen some short interview clips with him and it seemed like he was proud of how cheaply and recklessly he was doing shit. I’d only have to talk to the guy for five minutes and make up my mind I’m not getting near anything he’s doing. Those ill-fated tourists had conversations with him a lot longer than that.
Reminiscent of these clowns and their deadly water slide
At 169 feet tall, Verrückt was the tallest waterslide in the world. Riders plummeted down the nearly vertical 17-story chute—taller than Niagara Falls—at speeds up to 70 miles per hour. German for “insane,” Verrückt was designed to challenge the laws of physics. Visitors flocked to Schlitterbahn Water Park in Kansas City, Kansas, to experience its thrill.
That is, until August 7, 2016, when the raft that 10-year-old Caleb Schwab was riding went airborne and hit a metal pole supporting a safety net, resulting in his decapitation and instant death.
Nathan Truesdell, a filmmaker from nearby Missouri, heard about the devastating incident on the news. “My first thought was that it must have been a freak accident—what a horrible, horrible story,” Truesdell told me. “But once I took a closer look, I started to realize how complicated this story really was, and how this could have happened to anyone who went down that slide.”
The story, it turned out, was one of gross negligence, lax state regulations, and the consequences of hubris. Truesdell’s chilling short documentary The Water Slide, premiering on The Atlantic today, uses news and promotional footage to depict the ill-conceived project and its tragic fallout.
I’m seeing a lot of misconceptions in the replies. You have it mainly right from a very high level.
The reason why prepreg “expires” is simply that the resin system is mixed before being impregnated into the fibers, so it starts the curing reaction immediately. These resin systems are usually designed to cure properly at high temperatures, typically 250-400F depending on end-use, but they’ll still slowly react at lower temperatures. To further slow the reaction, prepreg is kept frozen. Prepreg also has two types of expirations: “shelf life” and “out life”. Shelf life is how long it can last frozen. Out life is how long it can last at room temp.
Theres a few issues that can happen when using expired prepreg. It can be harder to laminate since it will be too stiff and not as sticky. It won’t cure correctly causing failures in the resin.
Expired prepreg can be recertified by testing the material for those types of failures. Check if the prepreg can fold over a certain radius and stick to a certain angle without sliding off. Cure a sample and test it.
How did this man find a lawyer to represent him? What a nightmare client he would be. Basically throwing around liability grenades like it’s nothing.
The lawyer just writes up the disclaimer you sign.
He’s not getting involved in your 500 atmospheres of pressure.
Yeah but your life would be hell if anything went wrong because the man really makes himself look negligent by bragging about the corners he cut.
Much like that carbon fiber, he expired, too.
Play shitty games…
I just wish he didn’t bring others with him with his hubris. The more info that comes out about this guy, the worse and sadder it gets
Expired CF is the least of the problems with this project. The overall design was fundamentally compromised.
If the guy weren’t dead he’d be sued to death.
Lol fiberglass
This is why submarines are built out of steel.
This “engineer” failed at math class.
