SpaceX successfully launches and recovers second Falcon 9 in 48 hours

I honestly thought this was common knowledge amongst people who know who Von Braun was.

He was a Nazi collaborator and party member in full blood. As you noted, explaining his actions with the camps he ran would be an interesting exercise for any apologist.

Well, let's talk about that. How many of those millions who were both in both industry and the military AND ALSO were rocket scientists?

> Note that unlike Von Braun many other Germany scientists and weapon designers were not members of the Nazi party (let alone enthusiastic members)

For example? I'm not here to post up your argument.

> Becoming a Nazi and joining the party is what a person consciously did either because they > believed in the ideology or they wanted to collaborate to further their careers.

It's not apocryphal to say that full German citizens not persecuted for the racial background joined the Nazi party to escape suspicion of infidelity to the Führer's master plan of Aryan takeover, especially if you were an intellectual. Let's bring up another member of the Nazi party: Oskar Schindler. Tell me your criticism of Mr. Schindler. Was he acting in a purely selfish way?

> There is also the small matter of the war crimes he took part in with the enslaved labor at his factory in Peenemünde.

OK, let's talk about another German with the scientific mind whose knowledge and genius was enough to kill thousands of people: Albert Einstein. Do we blame him for Hiroshima, Nagasaki, the Cold War, and the tens of thousands of live nuclear warheads? His choice was similar: Death (as a Jew in Germany), or help make the A Bomb. Should he have chosen, "Death"?

First I've ever heard of that. Do you have any proof of that? If it was very controversial, there's sure to be articles and discussions about it, right?

Thank you for clarifying your previous post as this is what I was thinking you meant, but I didn't want to say anything without being sure. With that being said, and at the risk of sounding overly defensive, I do find it somewhat unkind to call into question the ethics and professionalism of those who work at SpaceX based on a movie about a completely different set of organizations and corporations. This of course isn't to say that there aren't valuable lessons to be learned from those past events, or that we are somehow immune from making similar mistakes, but implying that if such an event befell a SpaceX launch it would immediately be due to a lack of people giving it their best seems somewhat premature.

I do have a well read and marked up copy of both the Rogers Commission Report as well as the CAIB report on my bookshelf, so I can assure you that I and many others do take the lessons learned from those events very seriously. Thanks for the movie recommendation, I'll add it to my to-watch list.

I think the Space Shuttle engines would have been capable of more direct relights. They test fired them quite a bit and the were reusable. NASA was just taking a now risk approach and did not really push the technology forward.

Boeing has just received a contract for a first stage with wings that should fly 10 times in 10 days and it essentially uses a SSME. So they seem to believe that they don't need to do that much to make it work.

With regards to the SSME, the SSME is an engineering marvel, but it is significantly more complex than the Merlins you’ll find on Falcon, both in initial build as well as refurb. I know a few techs here who used to work on them at Rocketdyne. Raptor will be more analogous to the SSME but there have been significant advancements in metallurgy and materials science since the introduction of the SSME, which should hopefully lead to easier reuse. Also, it should be noted that the SSME were in fact refurbed and reused when they were part of the Shuttle program.

As to your quote from Quora, I find it somewhat ambiguous. Again, the SSME was routinely refurbed and reflown as part of the Shuttle Orbiter. I’m no expert on the SLS program, although I do keep up with things space related, but I’ve yet to see any cost breakdowns of refurb vs new build in regards to SSME specifically. That quote makes it unclear to me whether NASA found that reusing the SSME as part of the SLS program is cost prohibitive, or whether making the first stage of the SLS reusable, which happens to use the SSME, is cost prohibitive. It should be noted that the SSME and RS-25 are largely the same engine, and later flights of SLS will switch to a cheaper non-reusable version of the RS-25. In any case, the first stage of the SLS is going to end up in a giant pond of salt water, along with the attached SSME/RS-25s. SLS was never designed for propulsive landing, and can not be made to do so now, so those engines are ending up in the ocean no matter what. Perhaps the poster means that NASA found the refurb costs of the SSME to be prohibitive after they have been dunked in salt water, again, since this is the only possible outcome with SLS. Obviously if the first stage of SLS landed on solid ground, or a ship at sea, the refrub cost of the SSME would be completely different.

For the SSMEs, it was just plain use which damaged them. The SSMEs were engineering marvels, but the ludicrous nature of the Shuttle demanded extreme performance, which meant that they ran on razor thin margins. By the time they finished a ~8 minute burn, they had taken enough of a beating to need a lot of refurbishment. SpaceX's Merlins, on the other hand, are much lower performance and built more for robustness.

Think of it like an F1 race car, which needs a lot of work after every race and a new engine several times a season, versus a daily driver which can probably go 50,000 miles without ever opening the hood. (Not that this is recommended.)