SpaceX Texas launch site Discussion and Updates - Thread 12

[alugobi]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

[Tangilinear Interjar]

Makes me think of a giant Wicker Bill!

[InterestedEngineer]

Hi res slow-mo video of Booster startup.

Noticed how undisturbed the spin up gases are when a raptor is firing full throttle near it.  This means there is no exhaust rebounding inside the OLM.  The virtual blast deflector cone is doing its job.

Coolest "best part is no part" blast deflector I've seen video evidence for.

[alugobi]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

There's another peek at it in the latest video, but not much.  Photographers!  Are you allergic to the berm construction? 

Anyway, it looks like they're going to pour an upright wall extension on the top of the berm.  Can't tell if that's tied rebar or fencing.

[Nomadd]

 What things looked like a few minutes ago while I was waiting for a giant roll of Lifesavers to clear the road.

[alugobi]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

There's another peek at it in the latest video, but not much.  Photographers!  Are you allergic to the berm construction? 

Anyway, it looks like they're going to pour an upright wall extension on the top of the berm.  Can't tell if that's tied rebar or fencing.

Quoting myself to continue.  Just watched the RGV weekly video, and they have a good photo.  Here's a screenshot.  It's tied rebar.  They're building a pretty hefty deflector wall.  Don't know if it will go all the way across the berm, but on this side they're trying to protect the banks of He tanks behind the berm.

[alugobi]

And from Nomadd's photo above, looks like it's traversing the entire berm top.

[alugobi]

Forms being set under the rebar on top of the berm.  Looks like about a two meter extension.  From Lab Cam.

[SPITexas]

Anyone knows what this is near the cleared land. Close to the sub orbital site? Ground pic. From ocean cam
Arias from RGV photography showing where it’s at.

[OldSpaceFan]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

There's another peek at it in the latest video, but not much.  Photographers!  Are you allergic to the berm construction? 

Anyway, it looks like they're going to pour an upright wall extension on the top of the berm.  Can't tell if that's tied rebar or fencing.

Quoting myself to continue.  Just watched the RGV weekly video, and they have a good photo.  Here's a screenshot.  It's tied rebar.  They're building a pretty hefty deflector wall.  Don't know if it will go all the way across the berm, but on this side they're trying to protect the banks of He tanks behind the berm.

Wouldn't it have been easier to build the tower and the launch table 300 to 500 meters further to avoid all these protections with respect to the plumbing (and tanks) of the GSE? The proximity of these elements has always seemed very dangerous to me.

[FutureSpaceTourist]

The Orbital Launch Pad upgrades are underway, Booster 7 was rolled back to the Mega Bay, and work on Ship 25 continues in the High Bay.

Video and Pictures from Nic (@NicAnsuini) and Starbase Live
Edited by Sawyer (@thenasaman).

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L2 Boca Chica (more clips and photos) from BC's very early days to today.
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0:00 Booster 24 Outside at Starbase
0:16 Chopsticks Lowered and Opened
0:44 Booster 7 Rolled Off Launch Pad
2:46 Booster 7 Moved to Mega Bay
3:13 Work on Test Article Near Rocket Garden
3:28 Teams Working on Orbital Launch Mount
4:21 Workers Also Seen Near Quick Disconnect
4:36 Height Added to Berm at the Orbital Launch Site
5:07 Large Section Moved Onto OLM
5:26 Scaffolding Removal Around Ship 24
6:20 Ship 25 in the High Bay
6:35 Work on Ship 25 Inside High Bay
7:05 Nosecones Inside Tent 3
7:20 Front: Ship 28 Nosecone, Rear: Ship 29 Nosecone
7:35 Trash Cleanup Along Dunes

[tgr9898]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

There's another peek at it in the latest video, but not much.  Photographers!  Are you allergic to the berm construction? 

Anyway, it looks like they're going to pour an upright wall extension on the top of the berm.  Can't tell if that's tied rebar or fencing.

Quoting myself to continue.  Just watched the RGV weekly video, and they have a good photo.  Here's a screenshot.  It's tied rebar.  They're building a pretty hefty deflector wall.  Don't know if it will go all the way across the berm, but on this side they're trying to protect the banks of He tanks behind the berm.

Wouldn't it have been easier to build the tower and the launch table 300 to 500 meters further to avoid all these protections with respect to the plumbing (and tanks) of the GSE? The proximity of these elements has always seemed very dangerous to me.

-Given the location & environmental restrictions there's a limit to how far they can sprawl out the site.
-Since they initially planned for 2 towers & sets of GSE, they were probably trying to keep each Launch mount compact
-Shorter runs for the cryro propellant lines means less thermal issues.
-The high thrust-to-weight ratio of the booster means under launch conditions the stack will clear the pad pretty quickly. The static fires & testing actually expose the GSE to more heat & pressure than a normal launch should

[Bob Niland]

On the Stage 0 churn at BC, I've always found it to be unsurprising, given the long term objective of being able to have Starships (but not Boosters) land at, and perhaps take off again from, relatively austere off-world sites.

So in addition to "best part is no part",
there might also have been a bias for doing without:
- a Grand Canyon class flame trench,
- a tsunami-class deluge system, and
- Maginot Line-class GSE protection.

[InterestedEngineer]

From that ^^^ video, we see what appear to be blast deflectors being installed on the top edge of the tank farm berm.

There's another peek at it in the latest video, but not much.  Photographers!  Are you allergic to the berm construction? 

Anyway, it looks like they're going to pour an upright wall extension on the top of the berm.  Can't tell if that's tied rebar or fencing.

Quoting myself to continue.  Just watched the RGV weekly video, and they have a good photo.  Here's a screenshot.  It's tied rebar.  They're building a pretty hefty deflector wall.  Don't know if it will go all the way across the berm, but on this side they're trying to protect the banks of He tanks behind the berm.

Wouldn't it have been easier to build the tower and the launch table 300 to 500 meters further to avoid all these protections with respect to the plumbing (and tanks) of the GSE? The proximity of these elements has always seemed very dangerous to me.

-Given the location & environmental restrictions there's a limit to how far they can sprawl out the site.
-Since they initially planned for 2 towers & sets of GSE, they were probably trying to keep each Launch mount compact
-Shorter runs for the cryro propellant lines means less thermal issues.
-The high thrust-to-weight ratio of the booster means under launch conditions the stack will clear the pad pretty quickly. The static fires & testing actually expose the GSE to more heat & pressure than a normal launch should

I add trajectory of heavy debris considerations (heavy meaning the kind that can damage stuff, like chunks of concrete).

The farther away, the higher the debris are flying.  The taller any berm would need to be.

The closer, the lower the debris is flying, the shorter the berm would need to to be.

Although given recent construction, closer might have been better, since they are raising the berm in front of the tank farm another few meters.   This is why iteration and flexibility is good.  Easy fix, well outside of heavy flame or direct impingement, so easy fix.

[InterestedEngineer]

On the Stage 0 churn at BC, I've always found it to be unsurprising, given the long term objective of being able to have Starships (but not Boosters) land at, and perhaps take off again from, relatively austere off-world sites.

So in addition to "best part is no part",
there might also have been a bias for doing without:
- a Grand Canyon class flame trench,
- a tsunami-class deluge system, and
- Maginot Line-class GSE protection.

Yes, 110%.

Turns out the physics never required a flame trench for all the history of rocketry, because flow redirection can be done using the characteristics of the flow itself impinging on a perpendicular surface, which is a senior level college problem in fluid dynamics classes in mech. engineering and physics.  Odd, that that it took a company that is an expert in CFD to finally utilize the effect.

A bonus part about "best part is no part" is the trench and deluge system would have had a pretty significant environmental impact, the trench being below water table line and dumping of huge amounts of fresh water into a semi-saline environment.

I think the non-Maginot-line class GSE optimism has to await an actual launch to see if it works

[alugobi]

- Maginot Line-class GSE protection.

Nah.  Concrete chunks will just go around it on the north side.

[Herb Schaltegger]

On the Stage 0 churn at BC, I've always found it to be unsurprising, given the long term objective of being able to have Starships (but not Boosters) land at, and perhaps take off again from, relatively austere off-world sites.

So in addition to "best part is no part",
there might also have been a bias for doing without:
- a Grand Canyon class flame trench,
- a tsunami-class deluge system, and
- Maginot Line-class GSE protection.

Yes, 110%.

Turns out the physics never required a flame trench for all the history of rocketry, because flow redirection can be done using the characteristics of the flow itself impinging on a perpendicular surface, which is a senior level college problem in fluid dynamics classes in mech. engineering and physics.  Odd, that that it took a company that is an expert in CFD to finally utilize the effect.

Again, you're making a broad conclusion not supported by the evidence. There's more to a flame trench than "just" avoiding damage to nearby adjacent cryogenic tank farms, you know. There are distinct benefits to actively redirecting the flow in a controlled manner, allow it to diffuse and disperse safely. You might take a look at SpaceX's own flame trenches all around McGregor, Texas for example.

Further, CFD as a viable, affordable day-to-day tool has only existed within the last generation or so. Most rocketry in the history of the world predates it by quite a number of years.

[InterestedEngineer]

Further, CFD as a viable, affordable day-to-day tool has only existed within the last generation or so. Most rocketry in the history of the world predates it by quite a number of years.

I was making a juxtaposition between the solution being inherit in senior level college courses and a CFD expert company implementing it.  That must have gotten lost in translation.

I suspect Elon or one his proteges remembered his college courses, and told the CFD folks to go simulate it.

As far as McGregor, they use a very conservative traditional design, no blame and understandable.  They also don't have a huge circular area a kilometer in diameter between test stands to spread the blast out, sending it in one direction makes operational sense.

Boca Chica is the place for innovation and risk taking.

I'm also laughing, because I was a huge naysayer of the OLM upthread with the same arguments you had, until I figured out the math and source of the design.  I pray you can do the same.

[FutureSpaceTourist]

https://twitter.com/starshipgazer/status/1600366036783534080

Lots of work on and underneath the Orbital Launch Mount today. Plumbing work, shielding and tearing up concrete.

12/6/22

starshipgazer.com
patreon.com/StarshipGazer

[edzieba]

On the Stage 0 churn at BC, I've always found it to be unsurprising, given the long term objective of being able to have Starships (but not Boosters) land at, and perhaps take off again from, relatively austere off-world sites.

So in addition to "best part is no part",
there might also have been a bias for doing without:
- a Grand Canyon class flame trench,
- a tsunami-class deluge system, and
- Maginot Line-class GSE protection.

Yes, 110%.

Turns out the physics never required a flame trench for all the history of rocketry, because flow redirection can be done using the characteristics of the flow itself impinging on a perpendicular surface, which is a senior level college problem in fluid dynamics classes in mech. engineering and physics.  Odd, that that it took a company that is an expert in CFD to finally utilize the effect.

A bonus part about "best part is no part" is the trench and deluge system would have had a pretty significant environmental impact, the trench being below water table line and dumping of huge amounts of fresh water into a semi-saline environment.

I think the non-Maginot-line class GSE optimism has to await an actual launch to see if it works

Flow redirection isn't the only (or even the main) purpose of flame trenches (or water suppression, for that matter). And plenty of orbital launches have occurred from pads without them. Saturn IB even got two kicks at that can: the first being an elevated pad with a diverter sat underneath, and the second being the infamous 'milkstool' sat far above LC-39A.