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Artemis II is not safe to fly

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61–70 of 667 posts

Re: Artemis II is not safe to fly

#61

Can't they do a few loops around the planet and skim only the upper atmosphere? always worked well for me on kerbal space program, haha

Aerobraking causes heat cycles. Expanding and contracting a material that already has "not large, large chunks missing" doesn't seem very prudent. Even before the evidence of deterioration, I'm not sure the safety culture at NASA would reach for that any time soon when a single high-temp event would work.

Re: Artemis II is not safe to fly

#62

What I don't get is why the heck are the astronauts willing to risk their lives on something they must know by now is so dangerous? Is it really better to risk death than to risk getting fired?

This degree of lifespan-maximization is something you might have but others don’t necessarily share. E.g. old people went to Fukushima to sort it out. “Was it really better to risk death than to risk getting fired?”

Neither of these are major risks compared to never being what you want to be.

Re: Artemis II is not safe to fly

#63

Earlier quoted context omitted.

A rescue was impractical and potentially riskier no?

Riskier? Didn't they all die. Maybe if you ended up with 2 stranded shuttle crews, but correct me if I'm wrong, and I probably am, but couldn't the shuttle fly without any crew?

You can do a less risky thing and die or do a more risky thing and live. What happened doesn’t determine which thing is riskier just like I can call a 1 and roll dice and land it and you can call tails and flip a coin and not get it.

The outcome doesn’t determine the risk. I agree that this kind of office politics / face savings definitely is the cause of these two things.

Re: Artemis II is not safe to fly

#64

Earlier quoted context omitted.

Your link says it failed in testing, not in flight.

Did they demand an unmanned flight just to prove it worked? Or did they accept an entirely new design based on modeling and ground tests and then immediately flew it with crew on board? Then again I'm not one of those people who roots for NASA to fail for some reason.

None of what you’re saying happened.

They had a heat shield on the capsule that failed testing, so they swapped out the interchangeable heat shield for one that passed testing.

There was no entirely new design, there was no new material science, it was the same heat shield that the previous crewed capsules have used without the manufacturing defect.

Re: Artemis II is not safe to fly

#65

Can't they do a few loops around the planet and skim only the upper atmosphere? always worked well for me on kerbal space program, haha

This is actually what is thought to partially have caused the damage seen previously. The new trajectory is supposed to just have a single heating pulse instead of two.

Re: Artemis II is not safe to fly

#66
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…

About the last point:

At this point in time, manned space exploration should come out of our entertainment budget. The same budget we use for football or olympic games.

Re: Artemis II is not safe to fly

#67

What I don't get is why the heck are the astronauts willing to risk their lives on something they must know by now is so dangerous? Is it really better to risk death than to risk getting fired?

To be honest I don't know how close to non-fiction "The Right Stuff" (book or film) was but if you watch it you'd maybe gain an understanding for why astronauts do these things. At least that part is believable.

Re: Artemis II is not safe to fly

#68

Earlier quoted context omitted.

Did they demand an unmanned flight just to prove it worked? Or did they accept an entirely new design based on modeling and ground tests and then immediately flew it with crew on board? Then again I'm not one of those people who roots for NASA to fail for some reason.

None of what you’re saying happened. They had a heat shield on the capsule that failed testing, so they swapped out the interchangeable heat shield for one that passed testing. There was no entirely new design, there was no new material science, it was the same heat shield that the previous crewed capsules have used without the manufacturing defect.

> SpaceX's next Crew Dragon mission (Crew-5) will fly with a different, updated heat shield structure after a new composite substrate failed acceptance testing

I don't know what "new" or "different" or "updated" or "structure" mean then anymore.

Re: Artemis II is not safe to fly

#69

Earlier quoted context omitted.

How does SpaceX test it? Have they needed to solve this problem?

SpaceX tests these in prod. Kinda like Artemis I did.

And this is actually a decent strategy, but you can only really do this when you have lots of unmanned flights.

Re: Artemis II is not safe to fly

#70

Earlier quoted context omitted.

> I am very not brave but I'd volunteer. >> Artemis II could fly just as easily without astronauts on board

I think they were saying they would sign up just for the experience, even if it's unnecessary to the program.

But that was exactly the point I was responding to, no? If NASA was fine with skipping the astronauts, then they would just send it unmanned, not find a random volunteer.
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