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The newly assembled Liebherr 11350 (truly a monster) has just stacked the second steel truss section atop the first at the Orbital Launch Integration Tower.

Photo by Mary from an nsf stream this morning. The place where the segments mate is marked by scaffolding with boomlifts reaching up. Keep in mind that the tower is in the distance and bigger than it looks. The 11350 will probably need a boom extension in order to stack the highest segments. (nobody is sure how many there will ultimately be, maybe six.)

I also notice what may or may not be two heat exchangers on concrete pillars at the lower left. Haven't seen those before. Two more to come?

When Elon said that he planned to build a bar atop the High Bay, everyone thought, "That's just Elon being crazy again", and most people dismissed it. But recent construction work certainly looks like... a bar, or at least a viewing gallery with big picture windows, going in up there.

You can check it out in this video by a guy called 'Starshipgazer' who I believe is a regular in the LabPadre chat. He shows you closeups of building sections for the OLIT (orbital launch integration tower), the work on the viewing deck (bar?) atop the High Bay (above the scaffolding near the top of the highbay to the left, closeups verify glass windows), various deliveries, work on the OLT (orbital launch table) upon which Superheavies will sit on the pad, Sn 16 in the High Bay (work may or may not have stopped on it), then lots of construction-cam shots of the Launch Area featuring welders and guys tightening bolts on the OLIT, using what Elon has called "the hammer of persuasion". Very good video.

StarshipGazer also has some fascinating still shots on his twitter page showing a variety of unidentified mystery items, what appear to be robot arms applying thermal tiles inside the nosecone tent, and a weird hole in the side of a barrel segment with structural framing around it that (pure speculation) might be where an airlock will eventually go on manned variants and the HLS lander for nasa.

https://twitter.com/starshipgazer

https://www.youtube.com/channel/UCBVnapK...4phaGXxYng

Oh, and in other news, they seem to be preparing to remove Sn15 from its launch pad (Pad B) indicating that the decision has been made not to refly it. Presumably it will be scrapped.

So all indications are that we are in for a heavy construction period to prepare the Launch Area for orbital flights which are penciled in to start towards the end of the year. There will probably need to be pressure tests of the new Superheavy tanks before that happens, but maybe no hop tests. They might just power straight on to an orbital flight.

And I've heard speculations that when the Starship design is finalized and they know how they want to build them, the current Boca Chica Giant Tents might be torn down and replaced by a Tesla-style 'Giga-factory'. (Photo of the Tesla battery Gigafactory outside Reno. This factory produces more lithium-ion batteries than the rest of the world... combined.) Right now SpaceX is trying to figure out what kind of industrial space they will need and what kind of industrial processes they will use to mass produce Starships.



StarshipGazer captured the new things that I speculated in my last post were heat-exchangers and verified that is precisely what they are, for methane sub-cooling. I believe that the intention here is to recondense boil-off gas from cryogenic fluids, liquid methane in this case. Like a fridge for Really Cold fluids. The two that go on the remaining concrete pillars might be for LOX (?)

Sn15 has been transported back to the Build Area. It isn't clear what its future is now. It didn't end up going to the scrap yard but it might still end up there. It didn't go to the High Bay either. It seems to be sitting on a stand behind the High Bay next to the new propellant plant.

In this photo the newly installed windows of Elon's crazy StarBar atop the High Bay are visible. The High Bay is considerably taller than Sn15 but it's in the distance.

The landscaping is noticeable. There are lawns and pavement, it's less and less the dusty field with a single tent and some pickup trucks building Hoppy that it was a couple of years ago.

It appears that plans have abruptly changed after Sn15's success. There will no longer be additional test flights of the Starship second stage. Instead all efforts are being devoted towards preparing for the first orbital flight before the end of this year. (When strategic plans change like that, Elon's fingerprints are almost certainly all over it.)

Here's an artist's-conception video by Alexander Svan and the inimitable neopork showing the first orbital Starship reentering the Earth's atmosphere northwest of Hawaii.

Kind of idealized, admittedly, since most people expect it to fail at reentry and break up. The first orbital flight will be more about gathering engineering data. It will probably take several tries, just like the 'Crazy Elon' landing did.

They are currently stacking the next segment of the OLIT (orbital launch integration tower).



Photo by Mary

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Mary also reports that this giant grain silo thing went from the propellant plant area to the launch area today. Speculation is that it is a shell that will go over a cryogenic propellant tank to provide insulation. Dunno if it will contain a vacuum to form a giant Dewar, or what. Another one of these is under construction as well. (One for liquid methane and one for LOX?)

Here's an informative little video by Owe from the nsf forums that shows how the Cryo-shell in the photo immediately above is expected to work.

Check out Owe's youtube channel, his renders are very good and he illustrates lots of interesting engineering details

https://www.youtube.com/channel/UCRqNQqE...9A0Lpfxo6g

Here's Owe's weekly summary video. His renders show why even when there's no rocket launches, the Boca Chica Starbase remains a fantasy land for mechanical engineers.



And Lab got the shot below of two more methane subcooler heat exchangers heading for the launch area. (LabPadre photo from twitter.)

From the foundations being put in, it looks like there will ultimately be eight large GSE (ground support equipment) tanks made out of the same rings and domes that the Starships are made from. I guess that SpaceX decided why pay big bucks to buy super-large cryo tanks from a tank company when they already have an operation churning out rings and domes. (Rockets are basically big cryo tanks themselves.) Two of the GSE tanks are already in, so six more are expected. All will presumably have the big cryo-shells placed atop them by one of Elon's many cranes, with some kind of insulation (silica gel?) sprayed between the tank and the outer shell (doesn't look like its designed to hold a vacuum).

And what looked like eight bases for the subcooler heat exchangers have been seen either complete or under construction. So it's reasonable to expect eight of these subcooler/recondensers, one for each cryo-tank. Four methane subcoolers have already been spotted, but the bases for the other four appear to be a little different. Maybe the ones for LOX are different size or shape than the methane ones. I'll be curious to see them when they appear. (They appear exotic to me, but they are probably common equipment at petrochemical plants that handle liquified natural gas.)

There are now six of the recondensers at the orbital tank farm, both east and west of the giant cryo tanks. Some on the nsf forums have started calling them "hippos". (I like it.) They have started receiving manifolds and other plumbing. Starship Gazer reports that all six have "methane subcooler" labels on them. There isn't any sign of LOX subcoolers yet. Maybe they will just release the LOX boiloff into the air (it's just oxygen) and not recondense it and cycle it back to the tanks. They will have the air separation plant with its stories tall distillation column, pulling oxygen out of the surrounding air and liquifying it, so maybe they can keep topping off the LOX tanks with a pipeline that way. Can't just release methane boiloff into the atmosphere though, it's illegal. So it looks like the methane pressure relief is a closed-loop, with gaseous boiloff going to the recondensers where its reliquified and returned to the tanks.

Photo by Starship Gazer

The Bn 2.1 test tank traveled to the launch area today atop two SPMTs. This is a short "little" test tank with the Superheavy top and bottom domes. Of particular interest is the bottom thrust dome which has been redesigned (they keep trying to improve them) since their first practice Superheavy was scrapped a while back. The tank is sitting atop a test-tank torture device consisting of nine hydraulic cylinders to simulate the thrust of nine raptors fixed to the bottom dome. The orbital Superheavy booster will also have 20 more raptors around the circumference of the thrust skirt, but these will be attached to a structural framework and not directly to the thrust-dome. (For a grand total of 29 engines on the first orbital booster.)

The test tank will be pressurized to flight pressure and probably above, with cryogenic liquid nitrogen (not flammable or explosive). Then the thrust simulator rams will push up really hard on the bottom dome, as if rocket engines were firing down there. That's expected to happen next Monday.

Photo by Mary:

The Liebherr 11350 crane rose yesterday as crane-worshippers cried out "Rise, Kong! And become King of Cranes!" (no virgins were sacrificed.)

But it was not to be and Kong is again prostrate. The internet is alive with rumors. There's a story that there was radio frequency interference. There's people saying that sensors and a complete cable harness down the boom have to be replaced. And there's talk that parts have to be ordered all the way from Germany. It might all be true and consistent, or it might all be BS.

Photo by Starship Gazer of Kong in his glory before he returned again to earth. Kong's way off in the distance in this shot. The partially constructed tower next to him is already about 200 feet tall for scale.