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>The seal performed exactly as it was specified to. Yeah, no. The seal never performed the way it was designed to.[1] It was faulty by design. The seal always

>The seal performed exactly as it was specified to. Yeah, no. The seal never performed the way it was designed to.[1] It was faulty by design. The seal always leaked, but that didn't always lead to an explosion. There were multiple times where the erosion/blow-by problem was observed; in fact, the O-ring was (unsuccessfully) redesigned by Morton Thiokol to address the issue.[2] The problem was that nobody really understood what was going on, and waved their hands about it. Quote[3]: “NASA had developed a peculiar kind of attitude: if one of the seals leaks a little and the flight is successful, the problem isn’t so serious. Try playing Russian roulette that way: you pull the trigger and the gun doesn’t go off, so it must be safe to pull the trigger again.” Please do some due diligence before simply saying things that feel right for the sake of making a point. Your point still stands (it was an organizational failure), but premising it on a false statement (that the O-ring performed to spec) isn't a way to make it. [1] https://www.latimes.com/archives/la-xpm-1986-11-19-mn-4295-story.html https://www.latimes.com/archives/la-xpm-1986-11-19-mn-4295-s... [2] https://www.nasa.gov/history/rogersrep/v1ch6.htm https://www.nasa.gov/history/rogersrep/v1ch6.htm [3] https://lithub.com/how-legendary-physicist-richard-feynman-helped-crack-the-case-on-the-challenger-disaster/ https://lithub.com/how-legendary-physicist-richard-feynman-h...

dylan604 2y ago
> “NASA had developed a peculiar kind of attitude: if one of the seals leaks a little and the flight is successful, the problem isn’t so serious. this quote is also feels pertinent to the Starliner decision to launch. They knew there was helium, but they just decided there was more helium for the mission than was leaking. so the acceptable risk bar seems to be pretty low.
- bumby 2y ago
  It's prevalent all over the aerospace industry. It's also why the Columbia was lost (foam shedding happens but it's "in family" ie - it's a known issue that hasn't prevented a flight from being successful). Complicated systems are always having some issues that aren't to spec. The difficulty is assigning an appropriate risk to them. I've heard people who design 5+ sigma aircraft who refuse to fly on it because they know of some system that isn't up to spec in their eyes; in that case, the opposite is true: they're assigning a risk that is probably too large given the data.
dghlsakjg 2y ago
You wrote this after my other reply clarifying my point to a sibling comment that addresses exactly what you are saying, so please go back and read that. The gist of it is that the failure was expected by everyone with technical knowledge of the seal.
- romwell 2y ago
  Maybe read what you wrote instead? The words, not the gist. >The gist of it is that the failure was expected by everyone with technical knowledge of the seal. Nobody is denying that. What you wrote was, quote: "The seal performed exactly as it was specified to." That statement is false. It was not performing as specified at warmer temperatures either.

dylan604 2y ago

> “NASA had developed a peculiar kind of attitude: if one of the seals leaks a little and the flight is successful, the problem isn’t so serious. this quote is also feels pertinent to the Starliner decision to launch. They knew there was helium, but they just decided there was more helium for the mission than was leaking. so the acceptable risk bar seems to be pretty low.

bumby 2y ago
It's prevalent all over the aerospace industry. It's also why the Columbia was lost (foam shedding happens but it's "in family" ie - it's a known issue that hasn't prevented a flight from being successful). Complicated systems are always having some issues that aren't to spec. The difficulty is assigning an appropriate risk to them. I've heard people who design 5+ sigma aircraft who refuse to fly on it because they know of some system that isn't up to spec in their eyes; in that case, the opposite is true: they're assigning a risk that is probably too large given the data.

dghlsakjg 2y ago

You wrote this after my other reply clarifying my point to a sibling comment that addresses exactly what you are saying, so please go back and read that. The gist of it is that the failure was expected by everyone with technical knowledge of the seal.

romwell 2y ago
Maybe read what you wrote instead? The words, not the gist. >The gist of it is that the failure was expected by everyone with technical knowledge of the seal. Nobody is denying that. What you wrote was, quote: "The seal performed exactly as it was specified to." That statement is false. It was not performing as specified at warmer temperatures either.