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Comment by phkahler | Hacker News Reader

Let's look back at Star Hopper. SpaceX literally hired a company that builds water towers to build a prototype tank for Starship - and flew it! They were primarily trying to figure out how to build it, move it, etc. Obviously the risk tolerance was high. That's really the difference between them and say Boeing. SpaceX starts with higher risk tolerance just to figure out the lay of the land, but they start reducing that tolerance as development progresses. Boeing aims for perfection out of the gate (apparently).

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Alternative take: SpaceX is so new they don't know what they don't know.

Take their example of a failed F9 strut, where the material supplied by a vendor didn't come close to meeting the necessary specs. A mature aersopace company would have processes in place to check the material for these specs before use. SpaceX has since levied these new process checks, but prior to that failure lots people may have pointed to them as being more efficient because of their 'streamlined' process.

If you don't know something, your options are to pack up your bags and go home or try to learn.

Or, you can take a risk-informed approach, and understand what risks are prevalent (e.g., the risk of a bad vendor) and put the appropriate checks in place to mitigate that risk. "Learning" doesn't always mean taking the highest risk option and just rolling the dice.

Oh I totally agree, but that is a form of learning.

If you don't know what you don't know, you must find out.

I think the distinction I'm making is that the "form" of learning you take should be proportional to the risk and that all forms are not equal in value.

If you write a spec you've got to have some process to verify your stuff meets that spec. Otherwise you just wrote a fucking dream journal.

Indeed, and one way to verify you meet the spec is to test it, which they did and found it to be deficient. Having done so, they decided to improve their process. This is the definition of learning from your mistakes

Sadly, or interestingly, that was not an engineering lesson but a human one - don't trust the supplier.

Framed this way, I'm not surprised younger Elon's company missed it.

This is an really optimistic outlook. One way to test the rocket is also to see if it fails when humans are aboard. But it may not be the best way to balance risk and what you learn.

It would have been much more economical to test a coupon of the material upon receipt, like what is considered standard practice throughout aerospace companies. Or, like you said, you can blow up a rocket and launch pad instead. Same result, different risk profiles.

I don't think anyone would argue it would have been better had they known better and done things right the first.

The question is how you transition from the state of not knowing to knowing.

If you have poor processes and a lack of knoledge, how do you get better?

In this specific instance, the root cause analysis and remediation are vastly more complicated that presented in this thread. It is not like SpaceX wasnt doing testing on incoming materials at all or ignorant of the concept.

You’re right. Like most failures of this type, it’s rarely simple and these forums are super conducive to long-form discussion. They did checks, but they were inadequate.

Regarding knowing if you have a poor process or not, it depends on the uniqueness of your problem. For proteins that are relatively common, like material checks, you can shorten your learning process by looking at other organizations that have been through it for decades. For more exotic non-standard problems, you might have to learn the hard way.

A mature aersopace company would have processes in place to check the material for these specs before use.

Would a "mature aerospace company" also know to not use O-rings outside the temperature range specified by its engineers? Or know to test whether foam traveling at high velocity would penetrate the TPS?

Look, this is hard stuff. It's very easy to tell when you screw up, but very difficult to tell how close you are to screwing up. You're deluding yourself if you think some entities are immune to screwing up just because they've been around.

Whataboutism aside, I’m not delusional; I’m quite upfront that these types of biases exist at every organization that is staffed by human beings.

The difference is I don’t allow “gosh, space is hard!” as a rationale for thinking one organization is immune to those shortcomings. So instead of taking a look and asking something like, “Hmmm. Every other organization seems to have a supplier vetting process for safety critical stuff, I wonder if we should too?” We can instead just pretend we’re smart and different and be forced to learn already solved problems the hard way. The supplier thing is very standard quality control process stuff that transcends industry. Knowing if foam can penetrate tile or o-rings operate out of spec are not, precisely because they were non-standard conditions. That’s not to say that the decisions weren’t flawed, but I don’t think it’s as good of an analogy as you may think. Besides, the investigations largely pointed to broken cultures so I don’t know if that’s the type of company you want SpaceX associated with.

What’s the saying? “A fool learns from his own mistakes. A wise man learns from somebody else’s”

That's fair, my point was just that you made it sound like "mature aerospace companies" were some special beings that didn't make mistakes.

It's good to learn from other people's mistakes, but you also can't let everything people have done before go unchallenged or no progress would ever be made from rockets that cost $2B per launch.

Yeah, I realize now that probably wasn't worded as well as it could have been. To say it differently, I would expect well-run companies (whether 'mature' or not) to have the processes in place to better control the well-known problems. When it comes to those 'unknown unknowns' sometimes you can't learn except by trial-and-error.

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