
SpaceX’s Starship SN1 prototype blows up during pressure test on its Texas pad - eternalny1
https://www.geekwire.com/2020/spacexs-starship-sn1-prototype-blows-pressure-test-texas-pad/
======
grecy
Elon just said this 12 hours ago: "Failure has to be an option. What you want
is to reward success but there should be minor consequences for trying and not
succeeding. And major consequences for not trying #AWS2020" [1]

They are rapidly iterating, and I expect them to destroy up a lot of Starship
hardware in the next few months as they perfect it.

[1] [https://youtu.be/dPwxfzvhlLA](https://youtu.be/dPwxfzvhlLA)

~~~
nikofeyn
we've come a long way from "failure is not an option".

this is typical musk spin. of course we can't be afraid to fail, but that
isn't what happened here. catastrophic failures should not be considered "oh
well" situations. move fast and break things isn't a design and engineering
approach worth subscribing to. i'd appreciate a more measured response from
spaceX. the quote "Not much to worry about here" from spaceX is pretty
annoying. a less dismissive tone would be better, because from my point of
view, they just had a pretty large and expensive failure. that's bothersome
from someone getting a ton of public funding.

a response of "we take failures very seriously" rather than basically "yea,
that'll happen" would be more professional.

~~~
pdonis
If you don't own any SpaceX stock and aren't planning on flying on one of
their spaceships when the time comes, why do you care?

~~~
laichzeit0
How, exactly, would one own SpaceX stock?

~~~
babesh
[https://www.baronfunds.com/product-
detail](https://www.baronfunds.com/product-detail)

One of the Baron Funds invested in SpaceX.

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gpm
The pressure vessel failed during testing with nitrogen, no explosion
occurred.

This probably isn't that much of a surprise, they knew the welds were far from
ideal and already had improvements on the way.

> We had the wrong settings! To make the welds super flat & strong, we’re
> building a heavy duty, custom planisher, but just having the right settings
> is a major improvement.

[https://twitter.com/elonmusk/status/1232556310874533888](https://twitter.com/elonmusk/status/1232556310874533888)

The next version is already being assembled right beside where this one
failed.

~~~
Narkov
It definitely was an explosion. I think you mean it wasn't a combustion.

>explosion > a violent expansion in which energy is transmitted outwards as a
shock wave. > a sudden outburst of something such as violent emotion,
especially anger.

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bpodgursky
If the SLS blew up during testing, it would set the program back a literal
decade (or more).

If the James Webb telescope failed during deploy, it would be a $10-$20
billion loss -- and it would never be re-attempted.

NASA needs to re-learn from SpaceX's ability to iterate on cheap designs and
flush out flaws quickly. I say re-learn, because they DID know how to do this
correctly during the Gemini / Apollo eras (TONS of rockets blew up before they
attempted human spaceflight).

But culturally, something went deeply wrong, perhaps when we reached the Space
Shuttle era, and they lost the willingness to ever accept failure or pushing
limits -- the same process we tell tell children is critical to ever learning.

~~~
dredmorbius
Safi Bahcall's _Loonshots_ describes the phase-change transition which happens
in organisations as they grow in size and value safety over innovation.

[https://us.macmillan.com/books/9781250185969](https://us.macmillan.com/books/9781250185969)

[https://www.worldcat.org/title/loonshots-how-to-nurture-
the-...](https://www.worldcat.org/title/loonshots-how-to-nurture-the-crazy-
ideas-that-win-wars-cure-diseases-and-transform-industries/oclc/1129600169)

New Books Network interview: [https://newbooksnetwork.com/safi-bahcall-
loonshots-how-to-nu...](https://newbooksnetwork.com/safi-bahcall-loonshots-
how-to-nurture-the-crazy-ideas-that-win-wars-cure-diseases-and-transform-
industries-st-martins-2019/)

~~~
ColanR
It would be interesting to apply those ideas to American society in general.

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redis_mlc
Maybe somebody can explain this to me.

Welds are supposed to be tested at the weld level, not at the vehicle level.
So what is wrong with their process or QA?

~~~
frankharv
You are right. At the very basic levels we have PT. This is a test with dye
sprayed on the weld and a developer sprayed on to show the defects. This is
very commonly done.

Next we have UltraSonic(UT) testing. This requires expensive equipment and a
good examiner to interpret.

Third we have X-Ray. This is used on welds that are very important as it is
also hard to do and interpret. It also requires the weld to be ground smooth
to distinguish flaws from ordinary weld.

I am sure there are a variety of other non destructive testing (NDT
)techniques. These are the common ones used in industry.

I do want to mention that pressure vessels are hard to make. Especially
something so large. This could actually be a design problem and not welds.
Pressure vessels are often tested at 5/3 their working pressure. So failures
at testing are not uncommon.

~~~
frankharv
I really don't understand the build method they use. Ideally you would use a
turntable to rotate the cylinder while welding the sections together with a
sub-arc machine.
[https://www.youtube.com/watch?v=j-hfExEmGsE](https://www.youtube.com/watch?v=j-hfExEmGsE)

Elon blaming "settings" seems like a silly explanation. There should be weld
engineers and destructive testing done before the first beads are welded on an
actual tank.

~~~
gpm
> Ideally you would use a turntable to rotate the cylinder while welding the
> sections together with a sub-arc machine.
> [https://www.youtube.com/watch?v=j-hfExEmGsE](https://www.youtube.com/watch?v=j-hfExEmGsE)

Uh, at least in the video that steel is pretty thick. Starships skin is
slightly less than 4mm thick... while in that video they have a 2cm deep
groove, would the same technique actually work?

For what it's worth, ULA stainless steel (<1mm thickness) upper stages are
resistance welded instead
[https://www.youtube.com/watch?v=o0fG_lnVhHw&t=41m10s](https://www.youtube.com/watch?v=o0fG_lnVhHw&t=41m10s)

That said, I think a lot of the decisions right now are based on "what can we
quickly experiment with" not "what is a good long term plan". Building a 9m
turntable (diameter of the rocket) would take a long time.

~~~
frankharv
I agree a 9m turntable would take some time to make. But once made you could
crank these vessels out very fast. 4mm skin sounds OK and I am sure there are
some structural supports inside to keep it from collapsing. I am not a weld
engineer so I cannot say if Sub-Arc would be the best technique. I know that
ships skins are being built with it.

~~~
erikpukinskis
You’re talking about production engineering. You don’t really do that until
your design starts to be nailed down. It’s not.

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BooneJS
How much has SpaceX had to “start over” from what NASA and others have
researched over the decades?

