Scivillage.com Casual Discussion Science Forum

(Feb 9, 2020 11:14 PM)Yazata Wrote: [ -> ]Once they have the domes all set, they can make the fuel and oxidizer tanks bigger just by adding rings.

Elon: "Midsection of Starship propellant tanks"

https://twitter.com/elonmusk/status/1226782238035054592

Mary has some super-closeups of the rings and there's writing in grease pencil all over them. The engineers believe that it concerns inspections of the welds. Some of the writing says "RT Ok" and that might mean "radiological test" (X-ray). Others say "VT Ok" (visual test?) And there's lots of more cryptic stuff. Each 'ok' is initialed by somebody. In a few places you can see where welding was apparently redone.

So they are paying a lot more attention to their welds than they did with Mk.1/the Popper.

Mary also has photos of new added features being installed. For instance,

https://forum.nasaspaceflight.com/assets...612755.jpg

The fact that Elon is there, and the fact that he refers to these things as flight as opposed to test articles, suggests that they might be nearing the point where they start stacking. Elon's collecting the pieces, especially harder to manufacture bits, before he starts assembling them like Legos.

Here's what appears to be the current state of play, by an astute Nasaspaceflight.com commentator named Rafael:

https://forum.nasaspaceflight.com/index....3118;image

The vertical assembly building continues to grow taller.

Mary photographed this writing on one of the rings.

Don't tell MR!

Mary's out of action for a while. (She's ok but reportedly out of town.) But SpacePadreIsle has things covered. (He's one of Mary's friends, the guy she goes horse-riding with.)

Here's a newly assembled fuel (CH4) tank outside one end of the first giant tent. It's believed that this is flight hardware. 

https://twitter.com/SpacePadreIsle/statu...1903518720

And a short 17 second video showing some rings outside the other end of the same giant tent. Then some views of the Vertical Assembly Building (intended for stacking) extending higher and higher.

Elon's collecting all of his puzzle pieces and should be assembling them soon. The new SN-1 Starship should take form rapidly as all the cylindrical sections are piled up.

Then everyone expects a longer period of systems integration as plumbing, avionics and electrical cabling is installed.

There will be pressure tests at some point down at the launch pads, but unclear when that will happen. Probably as soon as possible, to avoid wasted labor if the tanks fail. You don't really want to build a whole spaceship around the tanks (like Mk.1) if you aren't sure the tanks will hold. If they do, then complete the thing.

https://twitter.com/SpacePadreIsle/statu...1617031168

gBb

(Feb 15, 2020 08:12 PM)Yazata Wrote: [ -> ]Mary's out of action for a while. (She's ok but reportedly out of town.) But LabPadreIsle has things covered.

Here's a newly assembled fuel (CH4) tank outside one end of the first giant tent. It's believed that this is flight hardware. 

https://twitter.com/SpacePadreIsle/statu...1903518720

And a short 17 second video showing some rings outside the other end of the same giant tent. Then some views of the Vertical Assembly Building (intended for stacking) extending higher and higher.

Elon's collecting all of his puzzle pieces and should be assembling them soon. The new SN-1 Starship should take form rapidly as all the cylindrical sections are piled up.

Then everyone expects a longer period of systems integration as plumbing, avionics and electrical cabling is installed.

There will be pressure tests at some point down at the launch pads, but unclear when that will happen. Probably as soon as possible, to avoid wasted labor if the tanks fail. You don't really want to build a whole spaceship around the tanks (like Mk.1) if you aren't sure the tanks will hold. If they do, then complete the thing.

https://twitter.com/SpacePadreIsle/statu...1617031168

gBb

I hope those "buildings" (especially the VAB) can survive hurricanes. Doesn't seem likely for some, given their tent-like nature. Permanent fabric structures can supposedly last from 20 to 30 years with minimal to no maintenance. But that surely doesn't take include extreme weather conditions.

(Feb 15, 2020 08:28 PM)C C Wrote: [ -> ]I hope those "buildings" (especially the VAB) can survive hurricanes.

I believe that the VAB is designed to. They put lots of effort into its foundations (remember the weeks of digging and concrete pouring?) And it obviously is reinforced by heavy steel trusses.

Quote:Doesn't seem likely for some, given their tent-like nature.

Sprung claims that their tents can withstand hurricanes. They boast that one of them used as a vacation resort/convention facility in Vanuatu withstood a Cat.5 cyclone with only minor damage. The locals used it as a storm shelter and it was filled with people. That was Cyclone Pam in 2015, with 250 kph/155 mph winds. (Added bonus: Vanuatu gets lots of earthquakes, and the tents can supposedly take them too.)

https://www.sprung.com/case-study/warwic...esort-spa/

Quote:Permanent fabric structures can supposedly last from 20 to 30 years with minimal to no maintenance. But that surely doesn't take include extreme weather conditions.

Yeah, the fabric might degrade over time with sun and exposure to the elements. But that might take decades, which is centuries in relativistic Elon-time.

Edit: They appear to be putting a roof on the vertical assembly building this afternoon. So it seems to be as tall as it's going to get. The engineers are speculating that they might have reached the limit of the top-of-the-line SX-180 boom lifts they are using: 54.9 meters/180 feet. The lifts look fully extended at vab rooftop height.

https://www.genielift.com/en/aerial-lift...ifts/sx180


gBb

The tank section of Starship appears to be pretty much stacked. (The stacking didn't take place in the vab, which kind of surprised me.) I believe that a few bottom rings with the bottom LOX bulkhead and the thrust structure remain to be added. (Last I saw, that segment was at the other end of the giant tent.) Right now they are struggling on getting the fit right on this larger cylinder and on welding it all together. (Outside, in the wind!) There's still a rough and ready 'slap it together' aspect to this despite the manufacturing methods having improved a lot.

That might reflect Elon, who wants to build these things as cheaply as possible. So he's not only experimenting with the rockets he builds, he's experimenting with how to build them. Start at the cheapest and simplest methods (mk.1, which didn't work), improve things a bit, test, then repeat that incremental process until it works with suitable safety margins.  A 'clean-sheet' design in more ways than one.

As opposed to doing things the old-aerospace way, where everything is based on existing design philosophies, is supposed to be as perfect as possible and where money was no object. Elon thinks that space travel will never work until it is affordable. (He wants to get the cost of access to space down to something in the ballpark of today's commercial airliners.) That calls for reusability (partially accomplished, since Falcon 9 isn't just a satellite-launching end in itself but is also a test article for this), large payload capacity (under development with Starship) and cheap manufacturing (I think that we see it under development here). 

The new SN1 cylinder now looks a lot like Poppy's ill-fated bottom half. There have been liquid oxygen and liquid nitrogen deliveries to the launch area, so a pressure test is probably going to happen fairly soon. Observers will need to look for upcoming road closures. (None announced as of now.) There's no point in completing this thing if it's just going to explode. So they will need to verify its ability to hold suitably high pressure first.

(Photo by Evelyn Arevalo)

Stacking underway. Tanks atop thrust structure. Watch live here:

https://www.youtube.com/watch?v=Op2sA0xqHtQ

Finished. The wind made it hard. The lower half section looks structurally complete. (Still needs welding the seam, piping and electrical.) Pressure testing to come next week.

New road closures announced (through next Saturday)

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

Thrust structure emerges from the tent

https://twitter.com/thejackbeyer/status/...9909996544

Picking up the tank section to place atop it

https://twitter.com/SpacePadreIsle/statu...0720231424

https://twitter.com/NASASpaceflight/stat...8192205824

The vertical assembly building (SpaceX calls it the 'High Bay') being topped off.

This takes courage. (Hopefully it's not why SpaceX is always looking for new employees...)

(Photo a screenshot from Gene/SpacePadreIsle's live-stream)



gGBb

Video of the stacking. The video includes audio of the guys in the boom-lift giving directions to the crane operator, so turn your sound on. Getting everything to line up is excruciating. (There are little guides on the top ring of the bottom cylinder that the edge of the bottom ring of the descending cylinder have to engage with. And the thing has to be rotated just right.) Lots of lower a little, no, go back up a few inches. Sometimes it looks good from the camera's angle, but a few of the guides aren't engaged right and they have to raise it and try again. The wind wasn't helping.

Finally it's down and guys climb inside through an access port. But parts of where the cylinders join was buckled a little, so we hear the 'Bang, bang, bang' of the "Persuader Hammer" that can fix anything. And indeed we see the dents pop back out. That little "Hammer of Persuasion" episode happens at about minute 19 in the video below and resolves about 2 minutes later.

https://twitter.com/elonmusk/status/1230278114179264512

Elon and his Hammer vs SN1 imperfections:



(Conventional aerospace must be aghast when they see this. But if it works... and costs a zillionth of how they do it...)

Spaceship construction at its grittiest. Building spaceships with a hammer! (Hammers and duct-tape. Together they can accomplish anything.)  

(The test of these methods will be next week in the upcoming pressure tests.)

Video here:

https://www.youtube.com/watch?time_conti...e=emb_logo

It was exceedingly foggy around sunrise today in Boca.

(Photo from LabPadre's stream)



When the fog finally burned off, the SN-1 tank cylinder had disappeared! It was gone!

It was soon located though, down at the launch area a mile away. They moved it by stealth, under cover of fog.

Mary's back from her trip and is on the job, and she says she has video of its arrival (atop those blue Roll-Lift crawlers) down at the launch area, but she hasn't posted it yet. A snippet:

https://twitter.com/BocaChicaGal/status/...9242651648

(Tesla's latest model, with Elon's 'Ludicrous' performance package.)

More, from Gene/SpacePadreIsle, showing SN-1 being greeted by Hoppy.

https://twitter.com/SpacePadreIsle/statu...6818027521

Right now it seems to be waiting for the Giant Crane to prepare itself to place it atop its launch platform, where the umbilical connections to cryogenic fluids (liquid nitrogen pressurant, fuel, oxidizer) plus electrical and data connections are located.

Edit: Mary reports that the Giant Crane has placed SN-1 atop its base.

https://twitter.com/BocaChicaGal/status/...5988727816

Complete video by Gene/SpacePadreIsle of SN-1 arriving at the launch site and being placed atop its platform:

https://youtu.be/220AeiF99fI

gGBb