Very scary.
Too many assumptions being made every time they made a change.
It is a miracle they went so long without such a tragedy.
Probably because it really is that bad. And Stockton Rush seems to come off worse every time someone else looks at the tragedy.
Me too. I actually watched this the day it came out, but I was doing other things so it was more like background noise. Now that I've rewatched it carefully, I'm chuckling at the "Wait, what?" moments I had earlier when he was pronouncing "hull" so peculiarly.
Indeed, the "Move fast and break things" strategy really only works when all that can be lost is your own money. Every day I'm more dismayed at how much further this sentiment has leaked into branches of engineering where it distinctly does not belong. If you want to build something to carry humans into a hostile environment, the right answer is still, "Move slowly and double check your work at each step."
I watched with closed captions and it was showing " hole" ..
Which could mean the person writing the captions was having the same problem as others with the pronunciation.
JayUtah is correct. It is speech-to-text software, so that transcripts and closed captions are automatically generated by AI software. This is often imperfect. Of course, if a person has a weird accent or weird vocal tick like in this case, speech-to-text software will hear the same thing we do, which is that the sound being produced is more like "hole" than "hull". It just writes what it hears. It usually can't infer what is actually intended if it differs from the actual sound being produced.
I do have a few.
I might be inclined to argue that you can still" move fast and break things", in the sense of doing a lot of all up prototyping and test flights, flushing out as many bugs as you can as quickly as possible. But I bet it probably takes time and care to get to root cause of each component failure.
If your glue turns to dust, you're going to have a bad day. But trying to sensationalize the surface area of the glue layer doesn't really impress me. We've been laying up aerospace structures using epoxy for many decades without issue. The wing spars on a Boeing 777 routinely exceed 500 sq ft of glue area. The shocking fact is not that so much glue was used, but that the engineering process did not include any direct-examination exercise to determine the effectiveness of their layup plan. They simply inferred success from final strain testing.
It necessarily did. The point was to smooth out imperfections in the fiber layup so that new fiber layers would have a perfectly cylindrical base to adhere to. In theory the layers were glued together and the glue baked to join it all together in one integral hull. But the video shows that this process did not work, and the engineers relied on tests that did not have the capacity to reveal that.
I don't disagree. I build a lot of prototypes. But "Move fast and break things" is not about learning more from prototypes than from whiteboard analysis or simulation. It's about a culture that rewards being first to market and can tolerate a high failure rate. The Silicon Valley software model emphasized a minimum viable product (MVP). Whoever got that first enjoyed an essentially winner-take-all payout. And as you conclude, that's acceptable for low-stakes stuff like some software that can tolerate a high failure rate.
Yes, for engineering but not so much for software. Software cost is just guys sitting at chairs. This is not to make light of the effort and skill involved. It's simply to say that the cost of iteration is considerably lower than building physical prototypes of actual objects. Either way, however, you have to be prepared to sacrifice economy for speed. You're trying to get to market first, or be the first to roll out a viable disruption. There really are few prizes for second place.
Exactly. Good enough in consumer or commodity engineering is general a much lower bar than good enough in something that people are going to trust their lives to. Your tolerance for failure in that case has to be much, much higher. That's when the procedure has to be, "Go slow and check each step."
I would agree. My manufacturing process involve some pretty straightforward steps that we can prototype effectively using 3D printers before we get into injection molding, chem milling, and 5-axis machining. We don't need a lot of whiteboard time, and we do a lot of physical modeling to shake out bugs in the manufacture and assembly. This used to take a whole DFM/DFA cycle that was its own department.
Gracias por la elucidación adicional!
An astute observation. During the space race, the Soviets were first to "market" with a lot of stuff, and it was objectively worse engineering but it got the job done. The Mercury capsule was technologically superior to the Vostok, but was a month late. The Gemini capsule was technologically superior to the Voskhod, but came later. The Apollo CSM was superior to the Soyuz at the time, and was available about the same time because NASA was fast catching up. But all those early Soviet successes were largely due to Krushchev insisting they move fast, break things, and be first to market.
He said they were the weak fibers snapping, leaving only the strong fibers. None of his passengers knew that it was simply cumulative damage, it wasn't going to stop once all the 'weak' fibers had broken.
It doesn't take much to debunk that excuse. Even if they were weak fibres, the fact that they snapped means that they were under tension and thus bearing some of the load. The load that they were bearing then had to be redistributed to the strong fibres until eventually, even the strong fibres are too weak.
The thing is he was bringing rich tourists down in the sub, not likely to be the kind of people with the knowledge base or experience for that kind of thinking.
I wonder if the pops could have been internal shear.
Well I thought of it and I'm not a materials scientist or an engineer. I don't think rich people are necessarily more stupid than I am, although, of course the ones that are less stupid than me probably wouldn't go near the sub.
I was wondering that too. I would have thought that most of the forces would be compression forces. However, I was replying to a specific claim that it was only the weak fibres that were snapping which implies tension.
I know you were, and that's still possible. Given the shear analysis we saw presented above, it's possible the inboard elements of each layer and/or of the whole bonded structure were subject to tension beyond their yield strength. But your mention of audible pops got me thinking about all the different things that could produce it. So I'm not contradicting you in the least. I'm just adding another, "It could also be..." hypothesis. If we see shear failure at the layer boundaries (and we do), then noise from shear failure is not surprising.
And why the soviet space program had so many more deaths. But think now you can be like a soviet cosmonaut just by flying in the US as the new moto of the FAA is move fast and break things coming from it being taken over by Space X.
You have the advantage of knowing the sub failed. They do not.
How many more deaths did the Soviets have?
Well they are leaving out the Nedelin event where between 50 and 300 people died.How many more deaths did the Soviets have?
They had fewer according to this wikipedia page, but it may be missing something.
List of spaceflight-related accidents and incidents - Wikipedia
en.wikipedia.org
It's not missing anything; you are. Scroll down to non-astronaut fatalities.How many more deaths did the Soviets have?
They had fewer according to this wikipedia page, but it may be missing something.
List of spaceflight-related accidents and incidents - Wikipedia
It's not so much that they are stupid (though they often are, inherited wealth is a great disguise), it's that because they often have others do their thinking for them (even in the case of "self made" ones), they've lost the ability to think critically, or never developed it in the first place.
Titan has always seemed a bit of a death trap to me, but the first time I heard of it, it had already puréed its owner and four other unfortunate passengers. Would I have the same opinion, knowing only that it had made several successful dives to Titanic? I'd hope so. There were some red flags, but would I have spotted them?
There are vanishingly few self made rich people. Even the ones that are considered self made come from a background of wealth or of sufficiently high class to have the right contacts. Unless you start from a high base in a capitalist economy it's nearly impossible to become rich, but if you're already there it's easy to become very rich.
Compared to the total population, maybe. Compared to two stupid self made very rich people in a death trap submarine, no.
Well no. Such people are not in the class of "self made very rich people" by definition
I think it's a valid point. Not on its own, sure, but in conjunction with the void fraction. If you've got, say, 10% voids but the area involved is really small, that may not be so consequential. But 10% voids on a really big area is a ◊◊◊◊ ton of voids. Giving a sense of how much voids there actually were seems pretty relevant.
And also achieving really low void fractions.
