I mean, that's how these heat shields work. They aren't reusable, you can't test them and then use them again. Or do you mean the design? We already did Artemis I.
It says that it is not safe to fly. They are sending humans without having tested in real conditions that their design was sound, GIVEN that the first time they did that (without humans), it turned out that their design was unsafe.
Statements like this:
"Put more simply, NASA is going to fly Artemis II based on vibes, hoping that whatever happened to the heat shield on Artemis I won’t get bad enough to harm the crew on Artemis II."
Are just so intellectually dishonest and completely ignore the extensive research and testing that's gone into qualifying this flight.
What would would help is if you said something like "Maceij says modeling a different entry approach on computers is no substitute for a bona fide re-entry testing a new design, but that's incorrect because _____."
Either theres a functional literacy issue here keeping you from understanding what it means to express a substantive thought or you overestimate other people's toleration for writing checks promising unmade arguments that never cash. You can't keep buying time with nothingburgers.
If that is so, put your money where you mouth is and place a bet on polymarket. If you are too scared to do so, then admit it to yourself, and understand that you don't believe this shit anyway.
Because you being a cuck for a contrarian for the sole reason that he is going against the grain is basically the same as Joe Rogan being anti-vaxx because its trendy and cool to think government=bad.
Aww, it would make me sad if people were betting on astronauts dying.
Isn't that a platform for insider trading? Not sure it qualifies here.
"Maciej says modeling a different entry approach on computers is no substitute for a bona fide re-entry testing a new design, but that's incorrect because _____."
The most clear cut indicator of intelligence is the ability to present both sides of the coin, and even more so state the conditions which make either side true or false.
The takeaway, is that the software was fine, but other systems like the main engine used too much cutting edge technology and have a lot of unexpected failure modes and too many problems like partialy broken parts that should no get partialy broken. [For a weird coincidence, Artemis II uses the same engines.] He concluded that when you consider all the possible problems the failure rate was closer to 1/100, but management was underestimating them and the official value that was 1/100000. [Anyway, the engines didn't fail in Columbia, it was one of the other possible problems.]
The articles explain that the shield has problems but management is underestimating them again. Let's hope the mission goes fine, but in case of a explosion it would be like a deja vu.
Much different than predicting future.
If you have 2 or 3 spare hours, it's worth reading.
The guy got a lot of first hand information about the Challenger disaster. He analyzed not only what went wrong, that is in the 20-20 category, but also what could have gone wrong, that is in the speculation category.
But if you read that report after the Columbia disaster, it's almost a premonition. He didn't identify the exact problem that caused the explosion, but the decisions that made that posible were quite similar.
They've changed the AVCOAT to be less permeable and altered the re-entry profile.
One of the findings of Artemis I is that lack of permeability led to trapped gas pockets which expanded and blew out pieces of heat shield. The reason for the change to be less permeable is to make it easier to perform ultrasonic testing, not to improve performance.
They altered the re-entry profile on the theory that the skip period contributed to spalling, but Charles Camarda disagrees in this doc: https://docs.google.com/document/d/1ddi792xdfNXcBwF8qpDUxmZz...
> Another chart which the Artemis Tiger Team did not intend to show on Jan. 8th, was the figure showing the spallation events as a function of time during the skip entry heating profiles (Figure 6.0-4 of NESC Report TI-23-0189 Vol. 1). In this figure, it was quite clear that the Program narrative they were feeding to the press, that it was the dwell time during the skip which allowed the gases generated to build up and cause the delta pressures which caused most of the spallation was, again, patently false. In fact, during the first heat pulse (t ≈ 0 to 240 sec), approximately 40-45% of all the medium to large chunks of ablator spalled off the Artemis I heatshield.
> Hence, varying the trajectory would do little to prevent spallation during Artemis II. I was never shown the new, modified trajectory at the Jan. 8th meeting.
I found this visual schematic of the spalling helpful - https://vectree.io/c/the-physics-of-ablative-spalling-in-ori...
It finally makes sense why the gas needs to leak out... if it gets trapped behind the burnt outer crust, the pressure just blows pieces of the shield off like a tiny bomb
Fixes have been made to the design, but they haven't been tested in flight.
So that means this capsule will fly a different re-entry profile to attempt to avoid the issue and Artemis IV will fly with untested fixes for lunar return.
Sort of. At a certain threshold, everything is untested. I’d put this closer to modified than untested—the general config was tested in Artemis I and the specific configuration in a variety of ground tests.
If it fails and the mission fails with loss of life while knowing it went ahead despite the IG report about the heat shield... It might be the end of NASA.
Hopefully it will return safely.
If idiots and emotions rein, maybe. Then the centre of gravity for space exploration correctly shifts to Musk and China.
The problem is that the purpose of NASA's manned spaceflight program isn't to explore space. It's to make the President look good (and I'm not just talking about the current one here) and funnel money to contractors. In that respect it's doing quite well.