SpaceX Starship test launch

[Alamo]

…

Did any of the corrective actions involve the launch pad and complex?

Yes. The 63 items listed in the report were very generic, top level summaries, e.g. “Redesign of pad deck.” There were three of them that dealt with the pad.

My personal theory on the first stage engine failures was that they just got wrecked by overpressure waves and debris from firing into a flat cement pad (which was basically destroyed).

I believe Elon stated earlier that the engines were not struck by debris. Any bits of concrete would have had to make their way back through the thrust of the 31 engines that were firing, and that doesn’t seem likely.

Aside from the couple engines that didn’t initally start properly, the report and Elon tweets? X’s’ mention that there were some fuel leaks that started a fire that cut communication between the flight computer and the gimbaling engines that resulted in loss of control. Also the hydraulics that powered the gimbaling of the engines leaked and caught fire as well.

The hydraulic actuators were replaced with electric ones on booster 9 (they did quickly so I think it may have been in the works before the launch) and they did some other things to stem the fuel leaks.

 

[printcraft]

I'm honestly surprised Biden hasn't ordered the FAA to put the brakes on all things SpaceX. Lord knows they're pissy over Ukraine and Starlink, to say nothing of the seething resentment at getting Twitter taken away from them.

Did any of the corrective actions involve the launch pad and complex? My personal theory on the first stage engine failures was that they just got wrecked by overpressure waves and debris from firing into a flat cement pad (which was basically destroyed).

Gigantic sections of steel plating over the blast pad with a immense water flooding system under the tower to stop that from happening were installed in the last couple of videos I watched.

 

[Ark]

Gigantic sections of steel plating over the blast pad with a immense water flooding system under the tower to stop that from happening were installed in the last couple of videos I watched.

They did install a water suppression system? That's cool. Old tricks are the best tricks, and Boca Chica is right on the water.

 

[Alamo]

They did install a water suppression system? That's cool. Old tricks are the best tricks, and Boca Chica is right on the water.

Not exactly. The “old tricks” don’t really work for what SpaceX is doing because what many don’t remember or realize is that during previous and current launches the pad and surrounding infrastructure were/are damaged. It wasn’t noticed much, because with the single use rockets and the months between launches, there was plenty of time to fix the launching apparatus, and it just didn’t get much press. In particular, looking at the Saturn V and space shuttle launches, everyone of them had damage to the launching structure. It got it down to kind of a dull roar, and it became almost a foot note in the post launch report, but they were always repairs needed. One time the space shuttle launched 1500 fire bricks out of the flame diversion trench.

SpaceX intends to rapidly relaunch the same boosters over and over, just like they’re doing with Falcon 9, but even more quickly. Bus they have to come up with an orbital launch mount and pad that sustains very little damage, so that it can be used again very quickly. That’s a big project by itself.

What they installed at Boca Chica since the last launch (which they had designed earlier, but it wasn’t ready for the first launch) is not really a deluge system, rather it is a flame diverter and cooling system.

They installed bunch more pilings under the pad, topped it with several meters of fondag concrete, and then laid a giant stainless steel plate over the top of the concrete. But really, it’s not a single plate, it’s a sandwich of steel plates that has channels running horizontally through it for highly pressurized water to flow through, cooling the stainless steel so that it does not melt under the assault of all that fire from 33 engines. There are several hundred, maybe thousand, holes drilled in the top steel plate that let the water escape so new cooler water can enter. Those holes are angled so that the water shoots out from underneath the booster in all directions, not directly at the engines. This redirects the thrust of the engines outward, and the rapid evaporation reduces the heat striking the plate (and everything else). It’s been tested a couple times at reduced trust levels, and so far so good. It will be interesting to see how it holds up to a full blast launch.

This is a test with water only, no rocket, on 7/28/23:




This is a static fire test of Booster 9 with the water system:

✂️ Booster 9 Static Fire

60 seconds · Clipped by Spectator1959 · Original video "Starship Super Heavy Static Fire" by SpaceX

youtube.com

This is a close-up of the plate showing the holes:

Full pressure test -credit SpaceX

youtube.com

 

[Ark]

Not exactly. The “old tricks” don’t really work for what SpaceX is doing because what many don’t remember or realize is that during previous and current launches the pad and surrounding infrastructure were/are damaged. It wasn’t noticed much, because with the single use rockets and the months between launches, there was plenty of time to fix they launching apparatus, and it just didn’t get much press. In particular, looking at the Saturn V and space shuttle launches, everyone of them had damage to the launching structure. It got it down to kind of a dull roar, and it became almost a foot note in the post launch report, but they were always repairs needed. One time the space shuttle launch 1500 fire bricks out of the flame diversion trench.

SpaceX intends to rapidly relaunch the same boosters over and over, just like they’re doing with Falcon 9, but even more quickly. Bus they have to come up with an orbital launch mount and pad that sustains very little damage, so that it can be used again very quickly. That’s a big project by itself.

What they installed at Boca Chica since the last launch (which they had designed earlier, but it wasn’t ready for the first launch) is not really a deluge system, rather it is a flame diverter and cooling system.

They installed bunch more pilings under the pad, topped it with several meters of fondag concrete, and then laid a giant stainless steel plate over the top of the concrete. But really, it’s not a single plate, it’s a sandwich of steel plates that has channels running horizontally through it for highly pressurized water to flow through, cooling the stainless steel so that it does not melt under the assault of all that fire from 33 engines. There are several hundred, maybe thousand, holes drilled in the top steel plate that let the water escape so new cooler water can enter. Those holes are angled so that the water shoots out from underneath the booster in all directions, not directly at the engines. This redirects the thrust of the engines outward, and the rapid evaporation reduces the heat striking the plate (and everything else). It’s been tested a couple times at reduced trust levels, and so far so good. It will be interesting to see how it holds up to a full blast launch.

This is a test with water only, no rocket, on 7/28/23:




This is a static fire test of Booster 9 with the water system:

✂️ Booster 9 Static Fire

60 seconds · Clipped by Spectator1959 · Original video "Starship Super Heavy Static Fire" by SpaceX

youtube.com

This is a close-up of the plate showing the holes:

Full pressure test -credit SpaceX

youtube.com

That's pretty neat. Hydraulic flame trench.

 

[Alamo]

That's pretty neat. Hydraulic flame trench.

Yes. The height of the OLM launch platform above the ground is about the same as the flame trench depth at KSC.

 

[Ark]

Yes. The height of the OLM launch platform above the ground is about the same as the flame trench depth at KSC.

Saves them a massive excavation project. Hope it works.

This is still an experimental system. Things are a ways off from the final itineration. Eventually all the launch support infrastructure will have to withstand a much higher launch tempo, but for the time being the point of the flights is to generate data and punch lists. "Every time something breaks, fix it twice as good".

 

[Alamo]

Round 2 next week. Probably. Hopefully.

 

[Ark]

Round 2 next week. Probably. Hopefully.

My bump helmet will save me if these spacecraft destroying charges suddenly decide to clack off

 

[Shadow01]

My bump helmet will save me if these spacecraft destroying charges suddenly decide to clack off

Had a summer job during college working at an industrial construction site. Boss gave me a hard hat to wear while massive I beams were being lifted overhead. I ask what good would the hard hat do me? Boss said the hat isn’t for you, it’s for us. Your name is inside the shell so we can identify the body.

 

[Ark]

Had a summer job during college working at an industrial construction site. Boss gave me a hard hat to wear while massive I beams were being lifted overhead. I ask what good would the hard hat do me? Boss said the hat isn’t for you, it’s for us. Your name is inside the shell so we can identify the body.

My hard hat is the one with the Palmetto sticker on one side and the ahegao girl sticker on the other side

 

[actaeon277]

Sometimes, people leave things on an i-beam, like a bolt or nut.
If that falls, that hard hat might come in handy.

Also, parts fall off cranes, walls, ceilings, etc.
Just because it won't stop a i-beam, doesn't mean it's not useful.

 

[Alamo]

My bump helmet will save me if these spacecraft destroying charges suddenly decide to clack off

Lol. But the charges do have to be installed in both the booster and the Starship, which involve manlifts and opening hatches and such. Multiple chances to bump noggin on things.

 

[Alamo]

FWS finished their re-eval yesterday and approved the deluge system (it’s really flame diverter, but everybody calls it the deluge) 30 uses per year. Runoff from the use of it amounts to less than the average rainfall event. Won’t disturb the salinity of the mud flats.

Environmental jihadists hardest hit.

Final FAA approval expected today or tomorrow.

 

[Alamo]

Also, maybe Spacex is going to build a second launch tower…

 

[Alamo]

In case you wondered what a launch license looks like:

https://www.faa.gov/media/69476

 

[bashMOH]

Hop wen

 

[Alamo]

Hop wen

Planned for Friday 17 Nov, launch window opens at 0700 CST for couple hours IIRC. If no launch then back up dates on Saturday and Sunday

 

[Alamo]

Launch delayed 24 hours while they swap out a part.

New date tomorrow 18 Nov at 0700 Texas time. Only 20 min launch window.

 

[Alamo]

Larry and I are ready for launch.