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Engineering assessment of the OceanGate Titan failure

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Re: Engineering assessment of the OceanGate Titan failure

#81

Post by King-Aaron »

DiggyJohnson wrote: post #46
hef19898 wrote: post #8

After an initial reluctance to follow this story, mostly due to the hysterical media coverage of a pointless rescue operation, my engineering half of my brain got interested. I am by no means a materials engineer nor a naval architect, but I was involved in some Design FMEAs and wrote thesis about the manufacturing of structural, pressurized aerospace carbon fiber parts. Some things I came across, which are in line w…

Off topic: do you not use a spell-checker?

In a multilingual world where we know that we all type at high speed on various devices, it stuns me when people still nit-pick on spelling errors. It's juvenile.

Re: Engineering assessment of the OceanGate Titan failure

#82

Post by anon_cow1111 »

kodah wrote: post #69
anon_cow1111 wrote: post #58

Earlier quoted context omitted.

>Edit: I looked it up. The human body almost instantly incinerates. It takes a matter of milliseconds. This is most likely BS- consider that a shotgun shell is made from a low melting-temp plastic and handles higher pressures and temperatures without issue (and repeatedly if you're reloading them). Probably your hair and light clothing would burn somewhat during an implosion, but would be extinguished as soon as the…

Feel free to give this a read, it has an answer for your assertion about waters role: https://mindofjp.medium.com/what-really-happens-to-a-human-b...

Ok, was able to read it finally thanks to the archive link someone posted below.

Yeah the "vaporizing" part is definitely wrong, as is the C4 comparison. It's pretty easy to figure out how much energy is involved. It's just a matter of multiplying the volume of the interior by the external pressure, in this case I don't know the exact dimensions, but the inside looks like at least 48" wide by 10ft long.

You'll end up with a number around 100 million foot-pounds, or 135MJ. (Or, for a more meaningful number, about the energy released from burning ~3 liters of gasoline).

Still an enormous amount of energy, and enough to turn people into tiny little pieces, but it isn't going to literally convert you to ashes like the article implies. It might barely be enough to boil 1 "person's worth" of water under ideal conditions.

Re: Engineering assessment of the OceanGate Titan failure

#83

Post by abestic9 »

King-Aaron wrote: post #81
DiggyJohnson wrote: post #46

Earlier quoted context omitted.

Off topic: do you not use a spell-checker?

In a multilingual world where we know that we all type at high speed on various devices, it stuns me when people still nit-pick on spelling errors. It's juvenile.

Up to a certain point it's not much of an issue, but I had to re-read several sentences and I'm fairly capable of following written text. It's also an accessibility thing, screen-readers and dyslexics might have trouble interpreting the text.

I support bringing it up when it's frequent enough to cause frustration. Putting some effort once into the writing - typing correction occurs almost effortlessly on almost any device these days - benefits every reader.

Re: Engineering assessment of the OceanGate Titan failure

#84

Post by tzs »

ghostpepper wrote: post #44

> Consider the fact that most engineers can explain the cause of the Hyatt Regency walkway collapse (if you can’t, you shouldn’t be an engineer), the Tacoma Narrows bridge failure, the Union Carbide Bhopal disaster, and the space shuttle Challenger disaster Does anyone know of a good documentary about famous engineering failures? Bonus points if they actually go into detail about the scientific explanation, as oppose…

I don't think it is currently available on streaming or disc, but if it ever becomes available again the TV series "Seconds from Disaster" [1] would be a good choice. It is excellent.

[1] https://en.wikipedia.org/wiki/Seconds_from_Disaster

Re: Engineering assessment of the OceanGate Titan failure

#85

Post by washadjeffmad »

hef19898 wrote: post #47
DiggyJohnson wrote: post #46

Earlier quoted context omitted.

Off topic: do you not use a spell-checker?

On mobile, regularly typing in three languages? No. Usually I don't write texts as long as that neither. Edit: My Pixel 2 trained muscle memory is just so slightly off at the new Pixel 7, you should see initial versions of my posts lately...

Gboard is atrocious. My typing accuracy dropped at some point while on my Pixel 3 XL and never recovered.

The crazy part is that I'm certain detection and text correction weren't always this bad.

Re: Engineering assessment of the OceanGate Titan failure

#87

Post by hef19898 »

carrolldunham wrote: post #80
hef19898 wrote: post #27

Earlier quoted context omitted.

The first thing I saw of Titan, while lookong for some footage of the infamous controller, was two screenholders, and that lightbar fr AliExpress or something, directly screwed into the inside of the hull... I honestely do not know what to say about all of this, which is actually pretty rare. I pitty the other four passengers, Rush got what asked for, and rightly so.

It was screwed into a floating inner liner cylinder which you can see in any video is separated from the hull. Get the facts straight before sounding off with gleeful incredulity.

Just rechecked a video, and there is some kind of liner used, to which the equipment is attached. I stand corrected.

There is nothing gleeful in any of my comments so, quite the opposite, I am really sad. Amd getting the facts straight requires a proper investigation, one that is happening. What I did was a superficial "FMEA" based on whatever, incomplete, information was publicly available at the time. Some is wrong, some is missing and some comes straight from OceanGate / Rush himself.

Re: Engineering assessment of the OceanGate Titan failure

#88

Post by 2-718-281-828 »

bboygravity wrote: post #17
hef19898 wrote: post #8

After an initial reluctance to follow this story, mostly due to the hysterical media coverage of a pointless rescue operation, my engineering half of my brain got interested. I am by no means a materials engineer nor a naval architect, but I was involved in some Design FMEAs and wrote thesis about the manufacturing of structural, pressurized aerospace carbon fiber parts. Some things I came across, which are in line w…

> Despite claiming otherwise on their homepage (archive.org still has it) they did attach equipmwnt directly to the carbon hull on the inside by screwing (!) to the hull. Result, all the fibers cut by the screws don't take any load whatsoever anymore, increased risk of delaminations (the hull is compressed, the screw on the inside isn't) This one is actually the most mind-blowing to me if true. That and the fact that…

> That and the fact that it actually made it to Titanic a few times and back without catastrophic failure.

i've no idea what i'm talking about but my guess would be that they were sort of aware of the design shortcomings and then just tried to compensate by overengineering the static components. and then they just pretended the material wouldn't progressively deteriorate towards the inevitable demise.

Re: Engineering assessment of the OceanGate Titan failure

#89

Post by 2-718-281-828 »

SV_BubbleTime wrote: post #19
jamincan wrote: post #6

Earlier quoted context omitted.

It's pretty much 1/3 the depth which is suspiciously close to a 3x safety factor which is what I've always heard engineers use. They certainly seemed cavalier with safety, so it wouldn't surprise me if they reasoned about it in that way.

A rocket might have a factor of safety of around 1.1. This is because at 1.3, they’ll never leave the ground. This is why they are so carefully monitored and tested, and still fail. It’s all relative. Good engineering doesn’t mean higher number. No one knows what the FOS for this sub was. Given the information from the CEO, things like that were just slowing down innovation! EDIT: Not all rockets, just using an examp…

very interesting point!

Re: Engineering assessment of the OceanGate Titan failure

#90

Post by hef19898 »

toss1 wrote: post #64

I own a carbon fiber design & manufacturing shop that does aerospace and undersea work. Watched the video by "Just Alex" and the section the bonding of the titanium end-caps and the cylinder absolutely gave me the creeps. The video was absolutely right to mention lack of dust-free environment (vs open warehouse), lack of temperature control, and lack of degassing equipment. We also have no idea about the properties o…

So I am not the only one who got creeps seeing the bonding video then. Wholeheartedly agree with your post.
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