Mary reports that there are day-long road closures tomorrow and that she has received one of the by-now-familiar over-pressure warning notices. (As we saw with the Sn4 explosion, they mean it.) Expectation is that they will conduct a static fire of Sn10 tomorrow. Which means that the launch area will have to be clear of workers.
Meanwhile today, the frantic construction madness at the Orbital Launch Complex relentlessly continues. It includes installing some unidentifiable pumps and valves inside the concrete and rebar blast-walls they built, then roofing everything with heavy steel I-beams. They have installed all kinds of pipes and conduits in underground trenches, now they are pouring a heavily reinforced concrete surface atop it. Presumably tanks will sit atop these surfaces and a new tank farm will appear, with propellants flowing through the pumps and valves in the bunker to the Superheavy atop the launch mount..
And the landing pad is getting lots of attention. They cut out a section of it and now they seem to be putting forms and rebar on top of it, presumably to expand, thicken and reinforce it. Presumably they decided that it was too small and they expect more prototypes to violently crash into it.
And they've been drilling deep holes for piles and putting long cylindrical rebar cages into them. It looks like what they do when they build skyscrapers in San Francisco. This will presumably be foundation for something heavy and tall. Speculation is a giant pedestal crane for stacking Starships atop Superheavies. And Elon still has his crazy vision of catching returning Superheavies by their grid-fins using the crane. (He wouldn't be Elon if he didn't have crazy visions.) That will put lots of stresses on the foundation of the massive tower crane and this is a swamp he's building in with very soft soil and bedrock so deep its halfway to China. ("I built this kingdom up from
nuthin'. Before I got here all there was was
swamp! They said I was
daft to build my castle in a swamp. So I did, just to show-em!")
A guy named Dayton Costlow has taken a whole bunch of photographs of the construction over the last few days and posted them here:
https://twitter.com/DaytonCostlow
To think that just a few months ago the Orbital Launch area was just a bare patch of dirt. In fact, when Hoppy flew maybe a year and a half ago, the whole launch area was little more than a dirt field. We used to joke about it. Aerospace hasn't seen things unfold at this pace since World War II, when new aircraft designs went from back of the envelope sketches, to prototypes, to production, in just a matter of months. Elon-time. Proved it can be done, if one has the will to do it.
Here's something informative about the physics of the Sn8 and Sn9 Starship flights by Declan of Flightclub. He's kind of famous for making spacecraft computer simulations.
He discusses things like the white plumes that come out of Starship along with the staggered one-by-one in-flight engine shutdowns during ascent that initially created consternation the first time people saw them. Had an engine exploded? (People were shouting 'Oh,no!') The consensus came around to the correct idea that the staggered engine shutdowns and the plumes were intentional. But nobody understood why if there's excess Lox in the tanks that needs to be dumped, why not just start out by loading less?
Declan explains it. (The excess Lox adds mass that prevents Starship from accelerating upwards too fast, since there's limits on how deeply Raptors can be throttled down without bad things happening. But as engines are shut off to keep Starship from blasting off into space, the need for mass to counteract the thrust goes down and Lox is dumped to lighten the ship.) There's a constant mass/thrust ballet going on.
This video has been endorsed by no less than Elon himself!
"Good analysis. We're working on lowering min throttle of Raptor, so that there is engine redundancy throughout the landing burn."
https://twitter.com/elonmusk/status/1360408418209591296
And here's Declan's earlier Sn8 video. Watch it, it's hugely informative! It provides lots of context for what he's doing in the Sn9 video. He discusses the kind of unknown variables that he needs for his simulations with his physics engine (dry mass, propellant load, thrust, aerodynamic forces, intended flight profile etc.) that the first time he just had to guess, not entirely correctly. Interesting information about the trans-sonic regime which starts at about 80% of the speed of sound and why SpaceX might want to avoid it on the first Starship test flights. (It starts slower than the speed of sound because some of the air flowing over the vehicle might be moving around the vehicle faster than the vehicle and there may be areas of supersonic airflow appearing.)
Marcus House (he's a Tasmanian who has a valuable space youtube channel) posted a twitter poll in which his readers could vote on whether they think Sn10 will successfully land. 64.1% say it will stick its landing, 18.1% say another RUD (explosion) and 17.2 said why try to guess.
Elon replied to the poll writing,
"Success on landing probability is ~60% this time."
https://twitter.com/elonmusk/status/1360774866023112704
Marcus' latest news update video, from yesterday (Saturday 2-13)
Marcus' youtube channel
https://www.youtube.com/channel/UCBNHHEo...LgqLKVugOw
Today (Monday 2-15-21) weather seems to have stopped everything at Boca Chica. Temperature is 24F/-5C (at the southern tip of Texas!) People in Minnesota will laugh, but its throwing southernmost Texas for a loop. It's windy so there are wind chills too. (They are more used to 100F down there.) There was rain so I expect that there's lots of ice. Driving conditions are bad. Locals are being warned about frostbite danger! Electricity is off, internet is history, all the Lab Padre streams are down, and it appears that the construction workers aren't at the launch area which has been a hive of frantic activity recently. The cold front has hit the area as hard as that little hurricane last year.
The SpaceX build site has its own generators and has Starlink internet connectivity, so it's ok. But Brownsville is offline.
There are 12.3 million electricity customers in the State of Texas. (Many are households with multiple people.) 3.6 million of them are currently without power.
Mary says there was ice on her car and on all the puddles this morning. But she was out taking her photographs as usual. Mary's like a Soyuz (but better looking), it takes a Sharknado to stop her.
She caught this very moody view out over the Gulf of Mexico from Boca Chica beach. Looks like a scene from a movie.
https://twitter.com/BocaChicaGal/status/...1088763908
Today (2-21) was seemingly devoted to pouring concrete at the landing pad. The pad's not only enlarged, it's apparently much thicker with lots of rebar in it.
https://twitter.com/BocaChicaGal/status/...3814524929
Mary noticed that Sn10 was flapping its lower flaps and tweeted about it. And Elon replied to Mary, writing
"Good chance of flying this week"!
There's been unofficial rumors from inside SpaceX saying that they want to conduct a static fire on Monday and fly late in the week. But I figured that if they just poured concrete on the landing pad, it would take longer than that to cure. At least a week. So I'm still a bit skeptical and expect 10 to perhaps fly the week after this coming one. Or maybe not.
We shall see. Flights can't exactly be conducted in secret since they involve published flight restrictions, evacuations of Boca and the build site, sheriffs roadblocks and all kinds of tip-offs of what's coming.
https://twitter.com/elonmusk/status/1363600651712794624
The thing that has Elon sounding happy might not be a lot of wet cement. Perhaps it's the news that the FAA has concluded its crash investigation of Sn9. Elon's been frustrated that the FAA has been treating each Starship that fails to land properly as if it was a crashed aircraft. It's slow and bureaucratic and threatens to make Elon-style rapid-prototyping impossible. Fly-Fail-Fix-Fly... over and over until it works. (It's how they taught Falcon 9 to land, something no other comparable rocket can do.) The FAA says that it's protecting public safety, which is a legitimate and important task. But I don't see how the Starship crashes are any more dangerous to public safety than successful landings. The ships had no crew aboard and there's no plans to fly people on board for many months yet, perhaps years. Both 8 and 9 steered to where they were supposed to go and crashed on the landing pad. And there were no people within five miles of that pad when the crashes occurred.
https://www.space.com/faa-closes-investi...-sn9-crash
About half an hour ago Mary tweeted that she received one of those overpressure warning notices for tomorrow, 9 am to 6 pm local. Combined with road closures that have already been announced, and it looks like a static fire is definitely planned for tomorrow.
https://twitter.com/BocaChicaGal/status/...8537701377
He hasn't been seen for months. It was feared that he was gone for good. But look who's back!
https://twitter.com/DaytonCostlow/status...4224824321
https://twitter.com/thejackbeyer/status/...4059793414
I believe that Boston Dynamics was giving out loaners. Adam Savage (of Mythbusters fame) got one to play with, test out and make youtube videos about. I expect that Zeus was one they loaned to SpaceX (a certifiably high-profile potential customer). So does Zeus' long-awaited return mean that SpaceX purchased him? (Spots are expensive for a guy like me, but pocket change for what some days is the world's richest man.)
Static fire/ignition test conducted Tuesday afternoon. It looked good to my layman's eye, but Elon tweeted that one of the engines was "suspect" (his word) and would be swapped out. (He has all the telemetry data and engineers.) Several thousand Lab Padre fanatics (including me) watched zoom closeups of the bottom of Sn10 all day today and eventually saw an engine removed. But as of 6:30 pm CST the new engine hasn't gone in yet. It's known that McGregor shipped a new one in and it's on site. Still no word on the numbers of the engine removed and its replacement. (But Mary never sleeps and watches like a hawk for that information. She has Jack Beyer, Dayton Costlow and other photogs in for the upcoming flight to assist her, so hopefully somebody will see it.)
Rumors leaking out of SpaceX suggest that the offending engine actually worked, and speculation is that it would probably work in flight too. (Explaining why the test superficially looked good.) But some of the tech data on it was said to be borderline and given the engine failure that doomed Sn9 it was decided not to take a chance and to swap it out.
Starting to look to me like they aren't going to get the flight off by Friday. (I have to go get my covid jabbing Friday afternoon, so I really hope they don't launch then.) If they get the new engine in overnight, they still need another static fire/ignition test. If it's tomorrow, that would mean flying the next day which is cutting things close. Which might end up pushing the flight back to next week. If the engine test slips to Friday, Friday will be out for flight presumably. (That's what I'm hoping... sorry Elon.) More time for them to get all their ducks in a row, more time for me.
Edit: 8:30 pm CST - new engine is going in now.
They got in a static fire/ignition test this afternoon. Looked good, but hard to tell just from looking at it if it was technically satisfactory.
Road closures for tomorrow have been cancelled, so it's clear that there will be no flight tomorrow. That's consistent with both a good test result and a bad test result. If good result, they will push forward to flight and may think that one day is cutting things too short. Monday would give them more time to conduct their flight readiness review. But if it's a bad result, they need to swap out engines again and conduct another ignition test. So nobody knows until either Elon tweets the results or we see what they do on Monday.
https://twitter.com/NASASpaceflight/stat...6588999695
Sn10 flight appears to be moving forward for tomorrow, Monday March 1
Mary reports that about 45 minutes ago she received her Boca Chica evacuation warning for tomorrow:
https://twitter.com/BocaChicaGal/status/...6999449603
10 has received its FTS flight termination system charges. (Plastic explosive charges designed to detonate the rocket if it veers towards a populated area.) This is one of the last things done before a flight.
https://twitter.com/thejackbeyer/status/...4277061632
And SpaceX knows how closely Mary watches them. (They love Mary and enjoy trolling her.) She grumbled a few days ago when a Raptor arrived without a visible number. (She keeps track of them.) So when a new Raptor arrived today, it had a huge "
47" on its bell, much bigger than necessary for their purposes. What's more, it had a cardboard sign on it that read, "
Wen Hop? Much Wow"! ('Wen Hop' is kind of an internet meme among the tens of thousands of Boca Chica watchers around the world. It comes from all the people who appear in social media chats asking when the Starship is gonna fly, often in broken English.
You can even buy 'Wen Hop?' t-shirts.)
https://twitter.com/BocaChicaGal/status/...8373371904
There could be a weather problem tomorrow though. A weak weather front will be moving through that might bring rain and cloudy skies. Maybe not, but it remains a concern. Tuesday and Wednesday are backup days.