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Artemis II is not safe to fly

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Re: Artemis II is not safe to fly

#371

Post by gramie »

Findecanor wrote: post #124

I have a bad feeling about this project. It reminds me of both the movies Capricorn 1 and Iron Sky ... and not in any good way.

Lots of people have bad feelings about things. If it all turns out okay, they generally forget about the premonitions. If it goes bad, then they believe that their gut instinct is reliably correct.

When I was small, I used to have bad feelings about my parents getting in a car accident every time they went out. It never happened, and they lived into their 90s.

Re: Artemis II is not safe to fly

#372

Post by nritchie »

Mikhail_K wrote: post #205
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…

> Challenger: no gasses were supposed to make it past the o-rings no matter what, > but when it became clear that gasses were escaping and the o-rings were being > damaged, there was a push to suggest that it's an acceptable level. Interestingly, the article https://docs.google.com/document/d/1ddi792xdfNXcBwF8qpDUxmZz... > by heat shield expert and Shuttle astronaut Charles Camarda, the former Director of Engineering…

Both things can be true. A better O-ring with the same joint might have prevented the disaster. A better designed joint with the same O-ring might also. Feynman knew that a little theater would go a long way. The O-ring explanation, albeit a partial explanation, made for good theater.

Re: Artemis II is not safe to fly

#373

Post by ibejoeb »

steve-atx-7600 wrote: post #13
johng wrote: post #2

Great read and interesting article. Hard to believe that NASA would risk astronauts lives simply to save face, but that appears to be what's going to happen.

Astronauts are smart folks. They can vote with their feet.

It's certainly about their lives, but it's also about not tanking the program due to catastrophic failure. The astronauts are going to do it regardless of the risk.

Re: Artemis II is not safe to fly

#374

Post by dataflow »

Isn't this the exact kind of scenario where you'd hope someone from above (like, idk, the president) would block the launch?

Not that I expect that to happen, but worth keeping in mind in case something horrible happens. NASA wouldn't be the only one responsible for lost lives.

Re: Artemis II is not safe to fly

#375

Post by monkeywork »

withinboredom wrote: post #254
rbanffy wrote: post #246

Earlier quoted context omitted.

> test the new heat shield which will replace the Artemis II design in an unmanned re-entry as well. NASA desperately needs more options. They shouldn't need to expend an SLS to launch an uncrewed Orion with a test heatshield on a trajectory equivalent to a moon return. They should be able to launch that on top of a Falcon Heavy. A Falcon Heavy can launch 63 tons to LEO and a fueled Orion plus service module weights…

I'd prefer if we just wrote off space-x and pretend they don't exist.

why because "elon bad" ??

cut your nose off to spite your face if you want but the rest of us will recognize the importance of space-x and be grateful it is here.

Re: Artemis II is not safe to fly

#377

Post by ramesh31 »

randomNumber7 wrote: post #294

I would like to understand why it happens so often to organizations that a currupted and dyfunctional behaviour takes over. And it seems to happen more often to institutions run by governments. Examples could be the Challenger disaster where managers overruled the engineers (who said in a meeting a launch was too dangerous) or the Boing 737max. Also a lot of companies in germany that I experienced (as employee and as…

>I would like to understand why it happens so often to organizations that a currupted and dyfunctional behaviour takes over. And it seems to happen more often to institutions run by governments.

Most people want nothing more than to complete a job to the satisfaction of their supervisor and go home for the day. When you get large groups of people together, this will always be the majority. Mission driven folks will always be crowded out of a large organization, replaced by careerists who play the meta game.

Re: Artemis II is not safe to fly

#378

Post by anonymars »

Mikhail_K wrote: post #353
mikkupikku wrote: post #232

Earlier quoted context omitted.

It's the same explaination. When the SRB joints flexxed the o-rings were meant to stay in place, but the joints were defective and NASA knew the o-rings were moving. However NASA also believed the o-rings could still take the abuse, because although they were moving they were getting shoved deeper into the joint, in a way that wasn't intended but was nonetheless at least marginally effective at stopping exhaust blow-…

> However NASA also believed the o-rings could still take the abuse, because > although they were moving they were getting shoved deeper into the joint, Why would they be "shoved deeper," when the problem is that the joint opens wider under load?

See here: https://www.researchgate.net/profile/Scott-Post/publication/...

What would happen "normally" (i.e. the normalization of deviance) was that the rotation (from the SRB joints bowing--essentially "ballooning") would create a gap, and the O-rings would get blown into that gap and ultimately seal in there

With Challenger, it was too cold, so the O-ring rubber was not malleable enough to seal into that space (like the O-ring towards the right of the diagram), so the hot gases were allowed to blow by and erode the O-ring. If they had sealed in (like the one on the left) it would have just taken the pressure but not worn away

Re: Artemis II is not safe to fly

#379

Post by njovin »

AndrewKemendo wrote: post #358
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…

It’s fundamentally a human coordination problem that cannot be solved The more populated and complex an organization gets it becomes impossible to maintain a singular value vector (get these people around the moon safely) Everyone finds meta vectors (keep my job, reduce my own accountability) that maintain their own individual stability, such that if the whole thing fails they won’t feel liable

It can't be solved 100%, but it can be _mostly_ solved with systemic buy-in to the safety culture. Commercial aviation is a great example IMO.

We've spent the last several decades making sure that every single person trained to participate in commercial aviation (maintenance, pilots, attendants, ATC, ground crew) knows their role in the safety culture, and that each of them not only has the power but the _responsibility_ to act to prevent possible accidents.

The Swiss Cheese Model [1] does a great job of illustrating this principle and imparting the importance of each person's role in safety culture.

A big missing piece with manned space flight IMO is the lack of decision-making authority granted to lower staff. A junior pilot acting as first officer on their very first commercial flight with real passengers has the authority to call a go-around even if a seasoned Captain is flying the plane. AFAIK no such 'anyone can call a no-go' exists within NASA.

[1] https://en.wikipedia.org/wiki/Swiss_cheese_model

Re: Artemis II is not safe to fly

#380

Post by aboardRat4 »

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…

>both cases some models were used to justify the decision, with wild extrapolations

Happens often. Just look at the climate change discussion.

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