Tuesday, March 30, 2021

Starship SN11 Discovers a New Failure Mode

Unfortunately, we don't know what it is just yet.  All we know for sure is what little we've been able to see with our own eyes.  SN11 lifted off from Boca Chica at 8:00 AM CDT, into a dense fog.  SpaceX's video stream, which included the usual photography from cameras around the ship, showed a seemingly normal ascent to 10km (6.2 miles), cutting off engines one at a time while climbing, until it hovered at altitude for a few seconds.  The descent looked normal (although they were losing video regularly) until the engines started up.  This was the last frame update from the vehicle.  As you can see, the mission time was 5:49.  This is 10 to 15 seconds before landing.  


This SpaceX mission video is part of a (much) longer video Everyday Astronaut posted that was live streamed this morning.  I've queued up the video to start around 38 seconds before ignition and liftoff.   Really of note is that there seems to be an explosion coinciding with the ignition moment in the picture above.  He has video of chunks of SN11 falling to the ground and is visibly worried about his cameras, set up where the chunks are falling.   Late this afternoon, Elon tweeted a reply to him saying, "Barely a scratch. :) Back on the stand soon! Will report conclusions as soon as we know them."

Did it explode due to something going on at this instant, or did the FTS (Flight Termination System) detect something so far from normal that it blew the craft?  Wish I could answer that.


I don't think it was the FTS deciding it had to destroy the vehicle.  The FTS system terminates a flight if it goes well off course or shows strong evidence of not being in control.  That takes time and everything was looking pretty normal until it didn't.  This looks to me like an engine explosion, from the things I can see.

As that second to last tweet says, SN15 is a few days away from the test stands to test "hundreds of design improvements" in all aspects of design.  Somewhere in the next couple of weeks, Booster BN1 will be brought to a different test stand for its testing.  In observing how quickly they were pushing to get SN11 ready to fly, I'd been thinking it was almost a formality to get SN11 out of the way and get onto testing 15, but learn as much as possible from 11 while you can.



9 comments:

  1. I also got the sense that SN11's imminent death and destruction was foreordained, and that they really wanted to clear the deck for SN15.

    Wonder what they learned from 11's death?

    But, well, still better than BO!

    Hmm, wonder if they're getting rid of early production Raptors that are just lying around in order to concentrate on improved Raptors.

    Lots of questions. Actions create questions. Questions bring results. Results bring further actions. The scientific cycle continues.

    This is so reminding me of the early days of Jet Fighters. They'd start building a model, identify an issue in production, fix it in the next model, sometimes even scrapping whole production runs to get to the next model.

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  2. I missed the launch and just saw the aftermath. Seems they wanted to get this launch off in a really bad way. And it ended up in a bad way. I really do think they were just trying to clear the suborbital launch stands. And they certainly did.

    I agree with Beans that this looks a lot like development from the 1950's, rockets as much as fighters. They lost a lot of rockets back then. Scott Manley has a very interesting video on the "first" NASA launch. It highlights the losses of launch vehicles in the late 50's.

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    1. I moved to this area they call the Space Coast at the start of the Shuttle era, but the people who lived here through that late 50's and early 60's period had lots of stories. It was fun to hear those.


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    2. Well, there was the string of Delta rockets that blew up because their explosive bolts were on the same frequency as the tracking radar...

      But, yeah, not the early days at all.

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    3. The joke Back In The Day was calling the Vanguard satellite "Rearguard". Blew up on live TV.

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  3. Was looking on YouTube for something else, and caught the headline in one of the Lab Padre windows.

    The have enough TLM data to figure out what happened, and I'm sure they'll release their findings, and go on the next LV.

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  4. Seeing rocket pieces fall out of the fog and kick up dirt was a new one.

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    1. There was one shot that Everyday Astronaut had that looked like it was a section of the bottom ring with one of the stubby landing legs on it. That was one of the peak moments.

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  5. I'm not saying it was aliens, but it was aliens.

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