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by rvnx 743 days ago
This is where it's actually interesting, it's not prototype -> live and boom.

It's the fifth mission or something, and worked for two years.

They actually went to the Titanic with that sub and previously succeeded to reach the Titanic, then it's later on, that the vehicle started to become fragile due to multiple reuses.

3 comments

> This is where it's actually interesting, it's not prototype -> live and boom.

> It's the fifth mission or something, and worked for two years.

Interesting how? I'm reminded of a quote from a famous failure analysis:

> We have also found that certification criteria used in [Mission] Readiness Reviews often develop a gradually decreasing strictness. The argument that the same risk was [deployed] before without failure is often accepted as an argument for the safety of accepting it again. Because of this, obvious weaknesses are accepted again and again, sometimes without a sufficiently serious attempt to remedy them, or to delay a [mission] because of their continued presence.

>Rather than warning of failure, Green explained that the sounds indicated “irreversible” damage. “It is my belief, substantiated by many years of experience, that composite structures all have a finite lifetime,” wrote Green, who died in 2021. “While I do not intend to be an alarmist, I did not sleep well and arose early to send this message.”

There sure does seem to be a lot of strong expert advice that was willfully ignored, per the article, that their materials choices, testing methodology, and damage monitoring system were setting them up for exactly the disaster that occurred.

And this exact failure mode of carbon fiber was well known and understood by engineers – and ignored by Rush.