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Mary's video of the apparently successful cryo pressure test.

https://twitter.com/NASASpaceflight/stat...5215845376

What surprised me is that the pad wasn't cleared of people and the road remained open to cars as they filled the test tank with liquid nitrogen. Presumably it wasn't pressurized at the time. It was a good thing, since it allowed Mary and her extraordinarily hi-def camera to be right outside the fence.

Good shots of the hydraulic cylinder at the bottom pretending to be a rocket engine.

There was even a crew that went up in a boom lift to install some test gear as the tank filled (and hissed ominously). People were joking that it was the engineer who didn't tell Elon about the weld defects on SN1. ("Elon justice")

Then the pad was cleared and the top pressure valve was seen to close as venting (and pressure relief) stopped.

Eventually pressure was released and the test tank came through seemingly unscathed.

All in all, it looks like a very successful test.

Edit: And Elon confirms it.

https://twitter.com/elonmusk/status/1237087558376599554

The test tank took a Sunday drive back to the build area this morning.

https://twitter.com/BocaChicaGal/status/...2047760384

Word is that Boca has a PA system for announcements that plays music much of the rest of the time. So we get this welder (watch with the sound on, video by Mary)

https://twitter.com/NASASpaceflight/stat...4770751491

Space Music!

Cameron county Texas, which includes Boca Chica, has been placed under a coronavirus shelter in place order. But SpacePadreIsle spoke to a SpaceX employee at Boca who said that they hope to get an essential industry exemption.

But lots of activity yesterday and today, so things definitely haven't slowed down.

First off, check out the new jewelry that Hoppy is wearing beneath its bottom skirt, installed in the last few days. Closeups reveal that they are rows of loudspeakers. It's probably part of the PA/music system. The engineers speculate that it's so Elon can play 'Ride of the Valkyries' when Starships roll out to the pad.

Big modifications were being done to the launch structure at the launch area yesterday. The larger ring-shaped structure was already there, but a massive new triangular thing was installed inside it. Speculation is that it's intended to support hydraulic pistons for thrust load testing of the new thrust domes. This is verified by closeups showing fittings corresponding the the locations of the three Raptor engines. So when the tanks are pressurized, three hydraulic rams will shove upwards to simulate the mechanical loads of three rocket engines firing at launch.

Photos of Hoppy's new look and the launch mount changes below. 

https://twitter.com/SpacePadreIsle/statu...7395139584

And Mary reports that the larger part of the latest Starship prototype's tank section (consisting of the top bulkhead, the CH4 tank, the common bulkhead and most of the LOX tank, on left inside the grey VAB in the photo in the tweet below) is about to be stacked atop the bottom skirt, the thrust dome and the bottom of the LOX tank, on the right in the highbay). A nose fairing sits nearby, but it probably won't go on top until/unless the tanks pass their pressure test.

The plan seems to be to fly this thing like Hoppy, just short VTOL hops up and down. There's no signs that it will receive fins or aerodynamic control surfaces.

Mary's photo of all that here. Click on it to get the whole thing uncropped. 

https://twitter.com/BocaChicaGal/status/...7170702336

So they seem to be approaching the third big pressure test of a complete tank section. (The first two unfortunately blew up.)

...Assuming that coronavirus doesn't halt everything.

Here's a big fat DUH for me. 

In some of the pictures that I've seen, it looked like shoddy work. I've thought to myself, what in the hell, but now I realize that it's just the reflection of clouds and other things, err.

Here's the current state of play, courtesy of Rafael Adami.

The sections in Mary's photograph are the yellow section (the tank section on the left in the twitter photo) the red section (the thrust section on the right) and the blue nose fairing. See the little man on the lower left, for scale.

Again, click on the image in the twitter post to get the complete uncropped version.

https://twitter.com/fael097/status/1242937212163051526

Edit: Elon's back in Boca.

https://twitter.com/elonmusk/status/1243073406884630528

Here's his photo of the same thing shown in Mary's photo from yesterday. Upper bulkhead, CH4 tank, common bulkhead and top half of LOX tank on left. Bottom skirt, thrust dome and bottom end of LOX tank on right. Plus assorted hardware attached to the outside for spinning up the turbopumps to start the engines, using bleed gas from the engines for tank pressurization, and lots of other stuff they still need to test. The hardware on the outer skin will be inside the skirt for flight versions, but outside where it's easier to reach and tinker with for this early test version that will probably only hop up and down like Hoppy. More ambitious flights to 20 km to test the landing maneuvers and then up to orbit to test reentry will need a smooth skin, control fins and heat shield tiles, so there's lots more to add.

Coronavirus or no coronavirus, Boca is rockin'.

The hydraulic cylinders have been installed on the recently upgraded launch mount.

The two sections of the incipient Starship in the highbay have been stacked one atop the other. (Photo by Elon)



The blue RollLift crawler is back and so is Berry, the Giant Crane.

https://twitter.com/JohnRand0061/status/...2193611776

And Cameron county isn't letting a little virus get it down and has announced a whole bunch of road closures.

http://www.cameroncounty.us/space-x/

Apparently next up is pressure tests on the new tanks in about a week. The last two of these big tank cylinders each exploded. Here's hoping that third time's the charm. I want to see it fly!

Somebody got their hands on SpaceX's applications for the road closures. (Dunno how, whether these are public records or what.) But whatever their provenance, the reason for a closure on Wednesday April 1 is given as 'static fire'. 



I'm frankly skeptical about that, since they would seem to need a pressure test first, and the test mount is set up with the hydraulic pistons to do that. But that's what this document says.

And here's an application for Monday April 6 where the reason is given as '150 meter hop' (the same altitude achieved by Hoppy).

I'm guessing that that in real life, April 1 will turn out to be a pressure test and April 6 might be a static fire after the hydraulic pistons are replaced by Raptor engines. But an actual flight might still be a ways off. (Will they make a very short hop of just a few meters before the 150m hop? That's what they did with Hoppy.) The whole thing might slip too. Perhaps it will take longer than anticipated to install the engines. (And maybe the whole thing will blow up during pressure testing. The first two cylinders before this one failed.)



And here's Labpadre's latest report on his new live-stream cam (on a 30 foot tower) and a video look at the Boca build area.

The Roll Lift crawler is... well, crawling... towards the build area. Screenshot from Labpadre's stream. The grey highbay in the top center is where the Starship tank section is. Just to the right of the highbay you can see Big Berry the Giant Crane setting up. It has a bent latticework extension attached that the engineers think is designed to enable it to reach more easily into the highbay above the cylinder, a tight spot that will call for some serious Matrix-style crane-fu. ('Berry' and 'Roll Lift' are the names of companies, that SpaceX contracts with for these specialized heavy-duty services.)

And to the right, in front of Mk.1's old nose, there's a new building going up (not a tent this time). The photo doesn't show it, but it's quite big. Smaller than the three Giant Tents though. Stargate is in the background, to the left of the highbay. It was there before SpaceX arrived and used to house a U. of Texas radio astronomy research thing, but word is that it's entirely SpaceX occupied now and houses their Boca Chica offices.

Mary's still out there, hoping to catch them moving the Cylinder to the launch area, expected to happen today or tomorrow. She actually has special dispensation. The county has ruled her 'media' and they are satisfied that she's practicing social distancing. So the Sheriffs know her and don't mess with her. SpaceX is satisfied that she sticks to areas where their security has said she can go, so they don't mess with her either. They have actually bent over backwards to be helpful to her. I expect that Elon recognizes the free service that she's providing to his goal of making the world excited about space again.

(Mar 28, 2020 05:30 PM)Yazata Wrote: [ -> ]Mary's still out there, hoping to catch them moving the Cylinder to the launch area, expected to happen today or tomorrow. She actually has special dispensation. The county has ruled her 'media' and they are satisfied that she's practicing social distancing. So the Sheriffs know her and don't mess with her. SpaceX is satisfied that she sticks to areas where their security has said she can go, so they don't mess with her either. They have actually bent over backwards to be helpful to her. I expect that Elon recognizes the free service that she's providing to his goal of making the world excited about space again.

Social distancing probably far less a challenge out there in tumbleweed country.

William H. Mercer: Tumbleweeds, equipped with speedometers, were released in a stiff breeze between Port Isabel and Boca Chica. [...] The elapsed time for the 900-mile run showed an average speed of 101.475 miles per hour, with short runs exceeding 151 miles per hour. The tumbleweeds were further shown to have planted 12,000 seeds per mile over the distance."

Other western weed specialists pulled in their yarns and quietly retired from the field. No western tumbleweed could match the Texas record. --Tumbling Tumbleweeds ... Reclamation Era, Volume 33, by United States Bureau of Reclamation