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Monty's avatar

Take # 2 needs to be expanded upon.

For the record I am a mechanical engineer with experience in both aviation and high pressure applications. This story is reading less like one of the "Brave Intrepid Explorer" and more like "Jackass - Deep Sea Edition"

First item to be addressed, the use of carbon fiber in the hull design. Fiber matrix components are goto material for light weight and areas where tensile loads dominate. This material not to be put under compression as it has only minimal load capacity. Fiber matrixes are also not to be exposed to environments where fiber delamination via the environment can occur.

Second item to address, is the lack of testing. A vessel design for 6000psi has to be physically tested far beyond that pressure (likely 1.5 to 3x the design load). This is to account for variations in the environment, flaws in material, and flaws in fabrication. For craft that are critical for human safety its best practice to test at least one article to complete failure.

Third item to address, is the lack of peer review. If you come up with a design that is outside traditional approaches it is extremely important to have outside parties review your work. This is done because it is very easy to get tunnel vision as a designer and miss an important detail. Refusing to do so is frankly arrogant.

Last item is LCF - Low Cycle Fatigue. I suspect this is the primary failure mode. When you repeated load a vessel to its close to its design limit you incur damage to the structure. After each cycle the absolute limit of pressure the vessel can take becomes slightly less than the previous cycle. Then eventually as the operator takes the vessel to a pressure limit they previously had descended to multiple times before, the material fails. This failure when it happens is catastrophic and completely unexpected.

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Robert F. Graboyes's avatar

In many ways, many or most of the pathologies of contemporary society have a common thread: ever-increasing risk-aversion and insistence that others share your aversion. At my own Substack (graboyes.substack.com), recent pieces have concerned college safe spaces, kids passing their childhoods confined to their own yards, the FDA's increasing resistance to drug and device approvals, resistance to self-imployment, rush to regulate AI. A friend's father worked on the Shuttle program at the time of the Challenger disaster. He said that the mistake in the run-up to Christa McAuliffe's flight was implying that spaceflight had become routine. Every flight, he said, was effectively a brand-new experimental vehicle and should be viewed as such. ... ... In discussing the submersible catastrophe today, I named someone who truly defied contemporary safetyism in the most iconic way. Barbara Morgan was McAuliffe's backup teacher for the Challenger mission. On YouTube, you can find a gut-wrenching video of her watching McAuliffe and their other six friends blown apart in the sky. And yet, despite that indelible memory, Morgan spent years reinventing herself so that, in 1998, she could qualify as a mission specialist and, in 2007, orbit the earth for 12 days. More like her, please. ... ... Make no mistake, what seems like mere virtue signaling by safetyists is really much worse. It is a concerted effort to shame those who take risks and to inform others that risk-taking is morally unacceptable. Unfortunately, as we know from a generation of cloistered childhoods, this social pressure works all too well.

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