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I do not know how much testing SpaceX did before launching their heavy rocket but it to blow up 3 mins later and call is a success seems a bit misleading. I understand they gathered data but to what end? They lost 3 billion craft. Lets say they do another test and it blows up 6 mins later for whatever reason. Another 3 billion gone. They do another test and goes for an hour and blows up during reentry. Then what? Is it still a success?

Why wasn't SpaceX heavy rocket tested thoroughly on ground before being sent to space? Assuming they took shortcuts and said screw it lets fire it up and see what happens, at what point will they say we are running out of money and cannot make anymore? Then what happens?

As an engineer and a software developer I test & retest and continue every possible testing scenarios before releasing code to production. I understand rockets and software developed arent the same but I feel public is being misled by "success" of this flight. Am I incorrect to assume that?

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    $\begingroup$ This Starship was always going to be lost, even if it worked perfectly. No landing attempt was planned for either the booster or Starship. $\endgroup$
    – Ryan_L
    Apr 22 at 21:43
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    $\begingroup$ The question in your title is good, but the opinions you are expressing in your question are leading to downvotes (not by me). Consider rewording it to leave out the editorial comments and just ask why SpaceX didn't do a more thorough ground testing regime. $\endgroup$
    – Organic Marble
    Apr 22 at 22:27
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    $\begingroup$ @SamB, 3 billion might be plausible for the total project cost since the first design studies in 2016. It's certainly not the cost of building a rocket. $\endgroup$
    – Mark
    Apr 22 at 22:35
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    $\begingroup$ Ironically, it's the ground that turned out to need more thorough testing. $\endgroup$
    – Cadence
    Apr 22 at 23:47
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    $\begingroup$ Considering that the entire NASA Artemis Human Landing System program costs less than \$3 billion, and includes, among other things, a completely new launch pad at Kennedy Space Center, the development of 3 new Starship variants, the building of between 3 and 20 new Starships and Super Heavy boosters, the development of a space suit, the development of in-orbit refilling, a demonstration flight for in-orbit refilling, crew-rating the Starship system, and two landings on the Moon, including one takeoff, it seems pretty obvious that the \$3 billion figure cannot possibly be real. $\endgroup$
    – Jörg W Mittag
    Apr 23 at 8:16

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It was tested heavily on the ground. Pressurization tests, fueling tests, spin-prime tests, static fires of all 33 engines individually and as a group.

Thing is, there are things it's impossible to test beforehand.

There are no hypersonic wind tunnels large enough to accommodate a 120-meter-tall rocket, and such a wind tunnel would involve energy levels commonly associated with small nuclear weapons. This makes it impossible to test things like the turbulence around the aft skirt and engines ahead of time.

There are no vacuum chambers large enough to accommodate such a rocket, or even the engine section alone. That makes it impossible to test how the exhaust expansion from 33 nozzles interacts at high altitudes, among other things.

There are no reduced-gravity facilities large enough to accommodate the rocket. This means you can't test things like the separation mechanism or the second-stage ullage system in flight conditions.

In software-engineering terms, this wasn't a production release, this was an integration test. SpaceX is doing something that hasn't been seen in aerospace since the 1950s: hardware-rich testing, where you rapidly iterate by building rockets, launching them, and seeing what breaks. It's a much faster way of designing things than the "analyze it to death" method everyone's used to, but it also produces more explosions.

This was booster 7 and Starship 24. Boosters 9 and 10 and Starships 25 and 26 are currently waiting for the launch pad to be repaired so they can be tested in turn.

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    $\begingroup$ Thanks for the detailed answer. I read somewhere that SpaceX motto is to Fail Fast and fix problems on next launch. But that approach has risks, financial risks. On the other hand NASA approach is to analyze every possible failure and mitigate risks which takes very long time. Perhaps you can add a few paragraphs about SpaceX approach risks $\endgroup$
    – Sam B
    Apr 22 at 22:14
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    $\begingroup$ Note that Booster 8, a near identical build to Booster 7, was scrapped. For B7/S24, it was either be expended in a test flight or be scrapped as well. These were old builds, with hydraulic TVC and other things that have been changed in newer prototypes. Their only value was as test articles, and they'd gotten just about everything useful they could out of B7/S24 without flying them. $\endgroup$
    – Christopher James Huff
    Apr 22 at 22:45
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    $\begingroup$ @SamB: The most expensive part of the Starship program is the development of the factory. You should really not look at the Starship program as a program to develop a cheap, fully and rapidly re-usable superheavy lift launch system but rather as a program to develop a factory to mass-produce a cheap, fully and rapidly re-usable superheavy lift launch system. In other words, SpaceX wants to become the Tesla of the launch industry: lots of companies build electric cars. But Tesla builds them faster than everybody else. If you look at it this way, then the vehicles come almost for free. $\endgroup$
    – Jörg W Mittag
    Apr 23 at 13:08
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    $\begingroup$ Case in point: SpaceX to date has built over 20 Starships (another 2 are almost finished) and several Super Heavy boosters (another one is almost finished). They are building them much faster than they can launch them: at this point, they have blown up 9, successfully launched and recovered 4, scrapped around 10 and they still have 3 ships and 1 booster sitting around ready to start their launch campaign. 7 and S24 were already obsolete: they use hydraulic thrust vector control, whereas SpaceX has switched to electric. B7's engine skirts were cobbled together, B9 has much improved ones, etc. $\endgroup$
    – Jörg W Mittag
    Apr 23 at 13:17
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    $\begingroup$ @OrganicMarble, there's also the need to provide 17 million pounds of tiedowns to keep the engines from trying to put the test stand into orbit. $\endgroup$
    – Mark
    Apr 24 at 7:29

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