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Artemis II is not safe to fly

idlewords.com

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Re: Artemis II is not safe to fly

#481

Post by trey-jones »

FrustratedMonky wrote: post #365
jessewmc wrote: post #355

Earlier quoted context omitted.

As an aside, do you have any suggestions for "state of the art" reading on safety culture?

I just had a conversation about engineers not understanding the need for grounding. I'm wondering if every generation has to relearn the basics for themselves through experience. Each generation has to make the same mistakes. Because book learning doesn't seem to do it for some things.

Sure. Even a history of safety success contributes to this. We haven't had an accident in 3000 days, what was dangerous about this job again? Also what's this stupid policy for anyway, I've never seen anybody even come close to (non-dangerous-sounding fate) while working here.

But probably the policy is in place because it used to happen before the policy was in place. It's just not obvious to people who have never seen the consequences before.

Re: Artemis II is not safe to fly

#482

Post by nostrademons »

randomNumber7 wrote: post #408
thesuitonym wrote: post #339

Earlier quoted context omitted.

``It is difficult to get a man to understand something, when his salary depends on his not understanding it.''

Isn't NASA run by the government? Why not pay people to do their job correctly?

Just because you pay people doesn't mean they do their job correctly.

It just gives you the option of not paying them if they don't do their job correctly.

Re: Artemis II is not safe to fly

#483

Post by tomjen3 »

inaros wrote: post #321
chadd wrote: post #292

I'm literally guest lecturing at a Harvard class tomorrow on systemic failures in decision making, using the Columbia and Challenger disasters as case studies, and changed my slides last night to include Artemis II because it could literally happen again. This broken safety culture has been around since the beginning of the Shuttle program. In 1980, Gregg Easterbrook published "Goodbye, Columbia" in The Washington Mo…

[flagged]

Didn't they have a crash dummy in it the last time? The data from buster should be able to tell us if the parachute worked or not.

Re: Artemis II is not safe to fly

#484

Post by falcor84 »

jonahx wrote: post #467
rjmunro wrote: post #349

Earlier quoted context omitted.

I thought I'd look this up. If you've had 9 successful attempts, assuming nothing has changed between them and no other prior knowledge about success probability, then Laplace’s Rule of Succession says the probability of the next mission being a success is about 83.3%, i.e. there is a 1 in 6 chance of failing next time.

> and no other prior knowledge about success probability This phrase is misleading, as Laplace's Rule of Succession is equivalent to assuming a uniform Bayesian prior over all values of p. That is, before any experiments, a 50% chance of success. Depending on the situation, this may be roughly accurate or wildly wrong. You cannot appeal to this rule to resolve the situation.

Well, obviously if we have a better prior, then that's better. But assuming no other knowledge, and especially if we think that other people's priors could be intentionally misleading, this rule seems to offer the best estimate.

Re: Artemis II is not safe to fly

#486

Post by chuckadams »

ibejoeb wrote: post #362
antryu wrote: post #250

mechanical engineering background here. the heat shield honeycomb → block change sounds like a classic cost/complexity tradeoff where you lose structural integrity for easier manufacturing. reminds me of automotive safety recalls that trace back to "simplified" component designs. sometimes the old complex way was complex for a reason.

I don't know anything about this program, so here's a basic question: why does manufacturing need to be easier? Are they intending to mass produce these craft?

Easier to manufacture usually means easier to reproduce. With something like this, you don't want variance.

Re: Artemis II is not safe to fly

#487

Post by xboxnolifes »

turtletontine wrote: post #74

Someone please answer my obvious question. We sent successful missions to the moon sixty years ago. What heat shield material was used for the Apollo capsules, and why would we need something different now? Are the Artemis mission parameters totally different in a way that requires a new design? Or was Apollo incredibly dangerous and we got lucky they didn’t all fail catastrophically? The article mentions Orion is mu…

Arguably, the goal isnt to go to the moon. Thats the mission, but the goal is to improve our capabilities of space travel. Improving our understanding and engineering of heat shields is one such case

Re: Artemis II is not safe to fly

#488

Post by xboxnolifes »

wiseowise wrote: post #81
idlewords wrote: post #76

Earlier quoted context omitted.

The Apollo command module used Avcoat, the same material as Orion. But there are two key differences: 1. The application method is different. Apollo applied it to a metal honeycomb structure with very small cells, while Orion uses blocks of the material. (NASA tried the honeycomb approach for Orion, but it was too labor-intensive). 2. Orion is much bigger and heavier than the Apollo command module. The informal conse…

> NASA tried the honeycomb approach for Orion, but it was too labor-intensive So cost cutting, as always.

Thats what engineering is. If you dont have to consider cost or labor, a lot of engineering becomes much easier.

Re: Artemis II is not safe to fly

#490

Post by gbgarbeb »

GMoromisato wrote: post #77

This is a more balanced take, in my opinion: https://arstechnica.com/space/2026/01/nasa-chief-reviews-ori... Camarda is an outlier. The engineers at NASA believe it is safe. The astronauts believe it is safe. Former astronaut Danny Olivas was initially skeptical of the heat shield but came around. And note that the OP believes it is likely (maybe very likely) that the heat shield will work fine. It's hard for me to r…

They have analyzed the problem with 1D non-coupled models that are so poorly matched to reality they would receive an F in a high school science class.

They are YOLOing it. It is insulting that clowns like yourself continue to cover for them.

NASA lowers its standards every time an accident happens. When they designed Shuttle, they intended for a failure rate of 1 in 10,000 or thereabouts.

Remember, it was meant to fly dozens of times per year. At the real failure rate, we would have lost dozens of Shuttles by now. The public would have shut NASA down in protest for massacring astronauts.

Good job moving the goalposts.

> They just slink away, and then when the next event happens, they cry wolf again. When they happen to be right 2 of ~130 times, they get to say "see I told you so!" and go on speaking tours about how they figured it out but NASA wouldn't listen, say they should be considered for a leadership position in NASA etc.

NASA does not have a single model that accurately predicts the heatshield damage. They are lying about this fact and crossing their fingers that all is okay. That might work in SWE's little AWS and GCP world, it doesn't work during hypersonic reentry. IOW they are gambling.

If you have a college degree, especially one that taught statistics, put it in a shredder and remove it from your CV. This is embarrassing.

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