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SN9

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Bob Zimmerman has a post up about today’s planned flight.

If it happens, it will have happened on the 35th anniversary of the loss of Challenger, and on my birthday.

[Update a few minutes later]

Looks like winds are too high, so they’ll miss the anniversary.

[Afternoon update]

Well, it looks like they are going to try today. They’re loading propellant, but there seems to be an FAA issue.

[Friday-afternoon update]

Well, here‘s what we know so far.

29 thoughts on “SN9”

  1. Here’s hoping, but on LabPadre’s channel they are saying it’s off for today due to wind.

    Happy Birthday, Rand!

  3. And now we learn what is triggering FAA to hold off on approval: “Reason for delay: FAA is basically giving SpaceX a hard time with the licensing because of the engine swap, it is technically a new vehicle.”

    Link: https://mobile.twitter.com/dsfpspacefl1ght/status/1354872818941317122

    Imagine if this rule were in place for commercial airline and air freight activity?

    And naturally David Portree does a drive-by to deliver his usual dose of SpaceX disdain. If it were up to him, the only launching that would ever get done would be by NASA, and carefully regulated ULA missions. Governmnt agencies *always* know best.

    1. a hard time with the licensing because of the engine swap, it is technically a new vehicle.

      If only the FAA thought this way when Boeing designed an old aircraft with a whole new engine. Alas, I doubt SpaceX provides as many jobs to former FAA executives.

  5. So, scrubbed again for Friday. Gee, I hope this new obstinance doesn’t reveal a new administration being (more) in bed with government contractors. They may find themselves in a court fight with the richest man in the world.

      1. Musk enjoys the approval of large parts of both parties. His cult status on the left will protect him. Biden probably wants to give him a trillion dollars to subsidize electric cars.

    2. Maybe if they make Hunter an astronaut the way Joe* got him that Naval commission, and promise to launch him, everything will suddenly be just fine. (Of course, they don’t have to promise to return him…)

  6. Well, with the delay we now get two Starships for our viewing pleasure! NASA would be beside themselves with three test articles on the pad at the same time! I’m thinking they probably won’t test 7.2 to failure with the other two present though.

  7. FAA appears to have stated their objections are specific to SN9. So now Musk has rolled out SN10. What will the newly liberated FAA do?

    It’s interesting how, between them, the Democratic Resistance and Never-Trump Republicans led to the Trump administration approximating the maxim, “That government governs best which governs least.” But it’s all over now, Baby Blue…

  8. It is also worth noting how close to Mexico Boca Chica is. Maybe Elon will just ferry the rockets to a new launch site a couple of miles south. The Mexicans would probably be more reasonable.

  9. I wonder if the delay is to make sure Elon doesn’t get Starship operational before SLS even makes it to the pad.

  10. Parsing the story very carefully from your last link, there were these quotes:

    Both the landing explosion and license violation prompted a formal investigation by the FAA,

    I find the wording of this phrase especially curious. Why the conjunction both? An unusual combination of two separate ideas. Was that a poor grammatical choice on the part of The Verge or was it something else?

    More ominous:
    driving regulators to put extra scrutiny on Elon Musk’s hasty Mars rocket test campaign.

    hasty is an interesting choice of an adverb. Was that an editorial decision on the part of The Verge or a reporter’s paraphrase?

    And finally…

    The so-called mishap investigation was opened that week, focusing not only on the explosive landing but on SpaceX’s refusal to stick to the terms of what the FAA authorized, the two people said. It was unclear what part of the test flight violated the FAA license, and an FAA spokesman declined to specify in a statement to The Verge.

    Transparency in government at work. If the investigation progresses the FAA will eventually have to disclose the nature of the violation because the AVpress. But from my reading of this story, which references two un-named sources, the choice of wording here would indicate that license violation had nothing to do with the explosive landing.

    I’m being esp. pedantic here precisely because the stakes are so high. For SpaceX AND the FAA.

  11. My biggest tee-hee over the Verge article was the use of the phrase “space skyrockets.” I can’t remember the last time I heard the word “skyrocket” used. Anyway, my earlier question is answered: it doesn’t matter how many Starships Musk rolls out. One FAA to rule them all and in the darkness bind them…

    1. My biggest tee-hee was the use of a picture of the now-ancient and no longer extant Starship Mk1 prototype as the story illo instead of a shot of either SN8 or SN9, the nominal subjects of the piece.

      More concerning is why the obviously clueless author of the piece was even assigned to write it. Was Loren Grush on vacation, out sick or otherwise unavailable? Is she even still employed by The Verge? If not, no one should, henceforth, pay any attention to anything published there about space as the publishers/editors are obvious idiots.

  12. Off topic, but can anyone access the Journal of Plasma Physics?

    An Alfvenic reconnecting plasmoid thruster

    Because the system-size plasmoid is an Alfvenic outflow from the reconnection site, its thrust is proportional to the square of the magnetic field strength and does not ideally depend on the mass of the ion species of the plasma. Exhaust velocities in the range of 20 to 500 km s−1, controllable by the coil currents, are observed in the simulations.

      1. Well, what she describes would be an impulse drive, though a very very good one. The later figure of 500 km/sec would be an ISP of 50,000, which is ten times better than VASIMR.

        I want to read the article to see more about it, and see if it looks technically easier than VASIMR or vastly harder.

    1. Okay, I’ve read the paper, suffering minor brain trauma because it’s plasma physics, and my knowledge of that won’t go far beyond general electromagnetic field theory and noting that conductive charged fluids in a field are going to do strange but entirely predictable things.

      The thruster’s construction and operation, on a basic level, looks to be easy peasy. You could probably build one in your garage out of some metal, copper wire, and some old electronics. You need a couple hundred volts for the plasma generator and to make an electric field, and another power supply to run a big solenoid.

      The B field she used in her simulation was 500 Gauss, which is only 10 times stronger than a refrigerator magnet, and a small fraction of what an MRI machine uses. The analysis and optimization of the thruster may be staggeringly complex, but basically, you apply electricity, inject ions (kind of like an old TV) and plasma goes blasting around like we see around stars, and then it goes shooting out the back with an extremely high ISP (up to 50,000 seconds in her simulations, and she hasn’t even optimized it yet). All the temperatures are low, and there shouldn’t be any wear.

      But like all such devices, the fuel consumption is low, the thrust is small, but the power demands are high, because all that KE in the exhaust plasma has to come from somewhere. She’s saying 5 to 10 Newtons per megawatt, which is pretty much the kinetic energy you’d be putting into any mass being ejected at that exhaust velocity.

      It looks easier than a VASIMR, since it doesn’t use staggeringly high temperature plasma contained in a magnetic bottle, and it doesn’t need a magnetic expansion nozzle. But like VASIMR, for a large ship it would require a large electric power source, ideally one with a great power to weight ratio.

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