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Tuesday, February 15, 2022

I Think They Call This a Slow News Day

Slow if you're not following the political drama.  Last week, the SpaceX facility at Boca Chica stacked booster B4 and Starship S20 for the third time, long enough for Elon Musk's talk with the dramatically huge stack ("largest rocket ever built") behind him.  This screen capture is from the next morning.

Yesterday, they de-stacked them again, moving S20 down onto one of their vehicle carriers. (Video version here). 

As we always do, observers started speculating that SpaceX is finally getting ready to static fire B4, perhaps firing up all 29 engines at once rather than starting with a smaller number.  Fueling that speculation (pun intended) was that over the last few days, SpaceX has had multiple liquid methane deliveries to their storage tank farm for the first time.  That article, from yesterday, includes a link to a six week old Twitter thread by a guy who claims to have oil and gas industry experience who simply blasts the way SpaceX built their tank farms.  They seem to have fixed many of the things he pointed out as bad or forbidden practices in the industry.  The Twitter thread (by Zack Golden) is worth at least skimming if you're interested in the details. 

A road closure had been scheduled for 10AM to 10PM local (CST) time today, so I opened a tab in the background to see if I could see anything.  That road closure was cancelled during the afternoon, so no tests today.  I expect them to roll S20 away from that position before they'd light B4.  It's not as close as it looks, that's the camera forcing perspective, but it's still kind of close. Road closures are scheduled Wednesday through Friday; the first two are also 10A to 10P, while Friday's backup closure is 6A to 4P.

There has been no announcement of an expected test or set of tests or when the first might be attempted.  Having said that, it's still possible some sort of new tests could start this week.

After seeing several reports that the FAA is delaying their approval, I went to the FAA Environmental Assessment Permitting Dashboard and can verify the earliest date for the release of approval for SpaceX to launch from Boca Chica is now March 28, slipped one more month from February 28th.

I don't think the first Starship orbital launch is likely to be immediately after March 28th, but before July seems possible. 



18 comments:

  1. I wonder who in the FAA is in the pocket of Bezos and all the legacy aerospace grifter companies?

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  2. The better question is, who isn't? The FAA is very big on their mission of promoting air traffic. Together with lobbyists led by pilots, they push back hard against any other use of airspace.
    This is one of the big reasons why space launches all happen from military ranges.

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    1. I hope you do not think that the military Safety organizations are any less restrictive than the FAA. And the Green freaks get just as righteously indignant at the ranges as well. The Eastern Range has to be concerned with scrub jays, gopher tortoises and indigo snakes. And cruise ships out of Port Canaveral. But at least the Buoy Club is no longer working out of Daytona!

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    2. In my experience, having worked on this at a military range, the difference is that the military is looking for ways to make the project happen, whereas the FAA is looking for ways to stop it if it's outside their traditional purview.

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    3. Back on Feb.4th, I was looking at data in an Ars Technica article saying Falcon 9 is now among the safest rockets ever launched. (bottom half of https://thesilicongraybeard.blogspot.com/2022/02/from-department-of-not-really-news.html )

      It looks like the most reliable rockets ever flown have gotten under 1% failure rate, but I don't recall any of them getting well past that, like down to 0.1%. That could be because none of them have launched enough times - except for the various iterations of Soyuz launchers all added up.

      Let's say the best rockets have a 0.5% failure rate, with no demonstrable proof. Now imagine if 0.5% of the ten thousand (or tens of thousands of) airplanes in the sky at any given moment came down every day. I don't think the FAA cares about that itself, just what happens wherever the rocket comes down.

      In this case, maybe it's that the FAA is out of their world.

      And maybe it's just another arthritic bureaucracy where everyone is counting down to a pension and they just don't care how long it takes.

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  5. I'm pretty sure I'd like way a lot more space between the propellant components that that. Anyone remember that old clip of the V2 that fell over during launch?

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  6. My ADD kicked in: Why is a screenshot from the East Coast timestamped with Central Time? Aside: I heartily approve of the simultaneous use of UTC: baby steps, y'know.

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    1. The screen capture is of Boca Chica, Texas, not the East Coast.

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    2. Ah. Thank you. I suspect my eye saw Boca Chica while my brain said Boca Raton.

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  8. If I understood correctly what ZG said he was of the opinion that ring stiffeners are members that strengthen against internal (sometimes external) pressure. In the tanks I have designed (meaning being part of the team) ring stiffeners are for preventing buckling of the shell. They actually cause some extra bending stress in the shell but that is more than covered by the increase in buckling stress. So they do increase the loading capacity in bending (gravity, wind loads) and axial loading (gravity) but indirectly.

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    1. Your experience far outweighs mine - I remember talking about buckling in some class back in college, but never worked in anything mechanical.

      What I got out what of I read is he was concerned about the shells bursting and that there were no stiffeners. He was also concerned about the berms around the tanks and flooding if something did burst.

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    2. Inside pressure is almost totally carried by the membrane stresses of the cylindrical skin. Outside pressure gets a lot more complicated. But the main point really is that they increase the load carrying capability, the details tend to get somewhat hairy mathematically.
      As far as I can recognize his other points are spot on, though if one of the methane tanks bursts it is not going to stay liquid for long but one does not want to be on the way of the methane tsunami so proper short term containment sounds a good idea.

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  9. This is the Serries that i want to participate and his mathematically logic was just awesome

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