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Artemis II is not safe to fly

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Re: Artemis II is not safe to fly

#561

Post by gbgarbeb »

NewsaHackO wrote: post #533
gbgarbeb wrote: post #490

Earlier quoted context omitted.

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 f…

You seem to have ignored an important statement in your reply. Will you be willing to put $20,000 on a bet whether or not the Artemis will have a catastrophic failure? Or willing to record a statement and release it on all of your social media if the Artemis does not have a catastrophic failure? It is extremely easy to sit on the sidelines at home and say to delay everything because something may go wrong, and you wi…

Ask Charlie Camarda.

Re: Artemis II is not safe to fly

#562

Post by eqvinox »

gus_massa wrote: post #525
eqvinox wrote: post #519

Earlier quoted context omitted.

I'm not super happy with the pattern of thinking in these numbers; arguing 1/100000 vs 1/100 for "accidents" is again a boolean thing. They probably had a very specific definition, which does make this viable, but we don't have that definition here. So the numbers are meaningless to us. And not having that definition, "accidents" is a sliding scale… e.g. I'm pretty sure astronauts injured themselves banging various b…

A high enough threshold for "accident" is a death. In the space shuttle the "accident" rate was 2/135 that is somewhat close to 1/100, but it shows that 1/100000 is too optimistic. You can pick a more strict safety criteria, but the result would be (something)/135 >= 2/135 > 1/100 >> 1/1000000

Yes… for the space shuttle. But where is what on this for Artemis II? Especially if it has more heat shield failure modes that are not immediately deathly, the whole consideration becomes non-obvious. Is it possible the astronauts will arrive back "well toasted" but alive and OK other than heatstroke? (Probably not, but that's the kind of question involved here...)

(Also, technically [you may begin your eyeroll] even death isn't a simple boolean condition. I guess brain death should do it.)

Anyway all I'm saying is that all of these considerations need more qualifiers to be really useful.

Re: Artemis II is not safe to fly

#563

Post by palata »

mmooss wrote: post #559
palata wrote: post #546

Earlier quoted context omitted.

> Putting people in a position where they need to treat their power with absolute humility or accept humiliation (and a major blow to their careers) in order to do the right thing is going to fail 99% of the time. I don't know... we select those people. Usually not for their ability to treat their power with humility, though. That's my argument in favour of quotas (e.g. for women): the way we select people in power n…

I think we already have quotas and affirmative action for white (Christian) males. Not long ago and maybe still true, more Fortune 500 CEOs were named John than were women. Though the policy is sometimes unstated (not always, especially in private, and the current administration is pretty clear about it), I think the data on the outcomes is overwhelming and undeniable. I think also that gender or skin color doesn't m…

I didn't mean that it was because of gender or skin colour. What I meant, really, is that we select the people who get power in some way. And then we complain that people in positions of power are like that.

My point was that there are probably a lot of "white old males" that just do not apply for positions of power, because they have learned all their life that they don't have the profile we usually select. And those may actually have qualities (like humility) that would make them better in those positions.

Now, it's difficult to say "this time, we will try to select a white old male who has humility, but first we have to convince him to apply even though he has learned his all career that it's not worth applying". But saying "let's try to hire a woman instead" may be a proxy to that. Sure, some women can be exactly like those people we already select (maybe Margaret Thatcher had a profile of the typical "old white male" that usually got into a position of power).

But I do believe that most women or people from minorities have a profile different from the typical "old white males" who are selected. So it may be a good proxy for "trying a different profile". The idea being that by trying a different profile, we may realise that it actually makes better leaders, and eventually the white old males who do have humility may get selected as well.

Not sure if I'm being clear? :-)

Re: Artemis II is not safe to fly

#564

Post by LorenPechtel »

cucumber3732842 wrote: post #495
oritron wrote: post #25

I haven't kept up with Artemis development but I've read extensively about Challenger and Columbia. These two parts of the article stood out to me: > Moon-to-Mars Deputy Administrator Amit Kshatriya said: “it was very small localized areas. Interestingly, it would be much easier for us to analyze if we had larger chunks and it was more defined”. A Lockheed Martin representative on the same call added that "there was…

>In both cases some models were used to justify the decision, with wild extrapolations and fundamentally, a design that wasn't expected to fail in that mode /at all/. Because, and it speaks volumes that nobody ever circles back around to this, that is absolutely f-ing normal. If everyone ran around like the sky was falling every time some widget made it into service and some unexpected thing was noticed nothing would…

The shuttle people never looked.

That there was blowby where there should be none was known, but nobody dug into why. There was no determination that it wasn't enough to be a problem, just an observation that it hadn't blown the booster up yet. For something with a wide spread in the data points, no way to model the maximum expected values.

Once they got serious about looking it didn't take much to reproduce the problem. They built a single joint, mostly filler inside, fuel to model the real thing during ignition. Maybe worked, maybe spot-welded, maybe complete failure. The colder the more likely to fail.

Re: Artemis II is not safe to fly

#565

Post by LorenPechtel »

IshKebab wrote: post #190
idlewords wrote: post #98

Earlier quoted context omitted.

If you play a single round of Russian roulette with a revolver, it is likely you will not die, but it is also not safe to do that. The same idea applies here. The foam shedding/impact problem was heavily analyzed throughout the Shuttle program, and recognized as a significant risk. Read the CAIB report for a good history. That report also describes the groupthink dynamic at NASA that made skeptical engineers "come ar…

But then no spacecraft is safe to fly. We're obviously willing to accept a much higher level of risk sending humans to the moon than in other situations. I think I read somewhere at a 1 in 30 chance of them all dying was acceptable. Not too far off from Russian roulette!

I don't see it so much as no spacecraft is safe to fly, but rather no spacecraft should have a crew on it so long as there are major safety questions.

This is not the Shuttle that couldn't be flown without a crew.

Re: Artemis II is not safe to fly

#566

Post by hajile »

Waterluvian wrote: post #317
Havoc wrote: post #268

Earlier quoted context omitted.

Suicide ideation and someone willing to take massive risks for something awesome are very different things

I'm sure the other astronauts are really looking forward to fly with a person showing signs of tolerating massive risks.

Historically, around 60% of all astronauts were from the military which is a high-risk occupation.

In the 50s, there was something like a handful of test pilots dying every single month. A subset of the ones who survived became the first astronauts. My understanding is that there are still a significant number of astronauts who were test pilots first.

If you don't have massive risk tolerance, you don't sign up for a moon mission.

Re: Artemis II is not safe to fly

#567

Post by LorenPechtel »

JumpCrisscross wrote: post #236
irjustin wrote: post #131

Earlier quoted context omitted.

> It's not like the NASA administrator gets a bonus when a rocket launches It's related to funding. I mean it's always money, right? But in Challenger's case, there was very heavy pressure to launch because of delays and the rising costs. I remember in a documentary they explicitly mentioned there was a backlog of missions and STS-51 had been delayed multiple times. To rollout/fuel, costs a LOT and challenger had bee…

> It's related to funding. I mean it's always money, right? This sounds more like there is money in the room than it’s about the money. None of the decision makers personally profited from saying go. It was much more of a prestige thing.

Challenger: Saying don't go would probably have cost them their jobs.

Columbia: It had previously barely survived foam damage. They figured out where the offending foam had come from and fixed that part--but only that part.

Re: Artemis II is not safe to fly

#568

Post by quasistasis »

fatcullen wrote: post #532
quasistasis wrote: post #193

It's not actually Avcoat. It was changed by LM. Thw honeycomb was removed. Imagine a beehive with no honeycomb and a slop of honey is what you have. Crystallized/solid honey, but honey never the less.

It is still Avcoat, that's just the name for the epoxy+silica 'honey.' But yeah they got rid of the honeycomb structure due to labour to manually fill the cells costing too much. Seems like kind of a dumb place to draw a line with the budget considering all the overruns it already has, means that now the Avcoat is being used in a design it wasn't originally meant for

If you want to be precise, sure. But most people don't make a distinction between AVCOAT 5026-39/HC-G and just AVCOAT 5026-39/HC and then AVCOAT 5026-39.

The key is that there's no honeycomb providing key structural support to the "honey."

Re: Artemis II is not safe to fly

#569

Post by LorenPechtel »

vannevar wrote: post #368
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…

All of the controversy over the heat shield is obscuring the much bigger safety issue: Artemis has had only a single unmanned test flight. By contrast, the Saturn launch system had seven successful unmanned tests before being trusted with a crew, including two unmanned flights of the complete Saturn V stack. And even then, three astronauts were lost during ground testing of the crew capsule due to a critical design f…

SpaceX was clear about their policy of flight testing earlier in the development phase. They expected to lose rockets, I do not believe those should count against the launcher.

Re: Artemis II is not safe to fly

#570

Post by LorenPechtel »

wolvoleo wrote: post #152
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…

In the space shuttle disasters the hardware had at least been used more than once. A huge lot of this one is only tried and tested on paper. And the idea that 'if we throw this much money at it, it really must be fine' I don't buy either. Look at how that worked out for Boeing. For all my feelings about Musk I would much rather step into a rocket that has exploded in all kinds of imaginable situations before so they…

I do not even remotely trust his management anymore. It looks very much like corner cutting. Cut until it fails and back off a bit is not a good approach when you need some redundancy.
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