totm nov 2023 SpaceX Discussion Thread

[tater]

8 hours ago, mikegarrison said:

I think it's obvious we are seeing one of the downsides to SpaceX's relentless "build them, fly them, break them" idea. When you have so many in the pipeline at once, you don't have the time to find and fix problems before you try to fly the next one.

SpaceX had to pull the plug on their production line and do a hard reboot, which is why they scrapped SN 12-14 (do I have those numbers correct?). So *maybe* this SN15 has the problems fixed, but if, for instance, they found a new problem with this most recent flight, they surely did not have time to fix it for the one that is sitting out on the pad now.

Good points, but assuming that Musk is not kidding about building a factory to make rockets, not individual rockets, the waste is not necessarily a problem. Each seems better than the last, and the early quality troubles seem fairly well sorted (build quality for Boca Chica, anyway).

Steel cost is not insane, and I would imagine a large chunk of cost is labor. At the point they can make X Starships per year, they might as well build more, the crew is paid anyway. If they scrap some... so be it.

Unsure on what engine costs are, he said the goal was $250,000 per engine. I'd not be surprised if it was 10X that.

[RCgothic]

THis is the latest on cost. Not sure what's changed since.

 

[mikegarrison]

(All this data from Google)

A 737 or A320 engine list price is around $13M. Of course, that's list price, not manufacturing cost. Some sources say that customers routinely pay 70% less than list price, or more like $4M/engine.

Now, these engines have to run for thousands and thousands of hours, not a few minutes. But still, I hadn't realized that advanced rocket engines are so very much cheaper than even single-aisle airplane engines.

[RCgothic]

Well, SpaceX's are. AJR's engines on the other hand...

[RealKerbal3x]

SpaceX are speedrunning SN15.

[tater]

Under 1M$? Wow.

In ~2 years they have built and tested 10 SS prototypes counting Hopper, but not counting the plain tanks (SN2, SN7*). So 1 every 2 months or so. The first year the number of employees was not as high as now. I think someone counted cars there and it was like 800. The place has to cost a couple hundred million a year to run, for 6-10 rockets?

Not too bad.

 

[StrandedonEarth]

And much of that is building out the factory and building the pads, mounts, and other infrastructure. Once construction is complete (if it ever is; it may never stop expanding) and all the automation is set up and ironed out (talk about Alien Juggernaut Factories), then staffing will drop.  How much staffing will drop is open for debate, depending how much they automate the process. I would think the basic tank/dome construction could eventually be fully automated, just like the rings already are.

[cubinator]

6 minutes ago, StrandedonEarth said:

How much staffing will drop is open for debate, depending how much they automate the process.

At that point, infrastructure staff will be offered to relocate to Mars to build infrastructure there.

[StrandedonEarth]

Just now, cubinator said:

At that point, infrastructure staff will be offered to relocate to Mars to build infrastructure there

You say type that in jest (I think), but that's probably already the plan...

[cubinator]

6 minutes ago, StrandedonEarth said:

You say type that in jest (I think), but that's probably already the plan...

Yeah I'm semi-serious. They are already building and launching these prototypes at record speed, and only want to go bigger. When they are finally launching to orbit multiple times a week, and able to send thousands of tons to Mars every window, who better to be the first crazy Martian constructioneers than the crazy people building a spaceport in a rural seaside village? They know what it takes to do the impossible and they'd be able to make sure it was safe enough for laypeople to follow.

I kind of want to go work there...

[StrandedonEarth]

4 minutes ago, cubinator said:

Yeah I'm semi-serious. They are already building and launching these prototypes at record speed, and only want to go bigger. When they are finally launching to orbit multiple times a week, and able to send thousands of tons to Mars every window, who better to be the first crazy Martian constructioneers than the crazy people building a spaceport in a rural seaside village? They know what it takes to do the impossible and they'd be able to make sure it was safe enough for laypeople to follow.

I kind of want to go work there...

Yes, you can go in your professional capacity of Chief Cricket Wrangler, training up the next generation of martian cricket wranglers.

Going off on a tangent (again), have you ever verified this for yourself?

Spoiler

The frequency of chirping varies according to temperature. To get a rough estimate of the temperature in degrees fahrenheit, count the number of chirps in 15 seconds and then add 37. The number you get will be an approximation of the outside temperature.

Source:

 

[Kerwood Floyd]

9 minutes ago, cubinator said:

...When IF they are finally launching to orbit multiple times a week, and able to send thousands of tons to Mars every window,...

I am a big fan of SpaceX, and am amazed at what they have accomplished so far, but I am going to believe they can do all that only when I see it actually happen.

[tater]

21 minutes ago, Kerwood Floyd said:

I am a big fan of SpaceX, and am amazed at what they have accomplished so far, but I am going to believe they can do all that only when I see it actually happen.

This.

I fully expect they get SS/SH working at some level eventually. A colony an Mars I believe when I see video of a colony being built on Mars.

[StrandedonEarth]

2 hours ago, tater said:

SS/SH

“Sssh” is similar to the sound Estes-class model rockets make. Starship/superheavy (will) sound nothing like that. But I’m being silly. 

Seriously though, the initial reports about the SN11 flight were confusing. First they said it self-terminated, then they said it had a RUD event. In retrospect, I’m guessing the telemetry said the FTS activated, then after further review they saw that a RUD happened first. I’m guessing the FTS activated when the computer sensed something was very, very wrong (after the RUD). 

But everyone probably figured that out for themselves. 

[RCgothic]

I wonder if the header tank imploded again.

Stir the tank, get an implosion, mix methane with oxygen, boom. They said they were taking the helium pressurant away again.

[tater]

 

[Lewie]

Do you guys think SN15 will stick the landing or RUD?

I’m betting on a landing

[Spaceception]

Either both, as a repeat of SN10 because it lands a bit too hard, or a good landing. I think they'll do everything they can to prevent it blowing up again or RUD-ing on impact

Edited April 3, 2021 by Spaceception

[StrandedonEarth]

Well, I don’t think they’ll launch in the fog again...

[Terwin]

7 hours ago, StrandedonEarth said:

Seriously though, the initial reports about the SN11 flight were confusing. First they said it self-terminated, then they said it had a RUD event. In retrospect, I’m guessing the telemetry said the FTS activated, then after further review they saw that a RUD happened first. I’m guessing the FTS activated when the computer sensed something was very, very wrong (after the RUD). 

But everyone probably figured that out for themselves. 

I'm pretty sure that they did not expect the FTS going off during this flight, as such, the FTS auto-triggering would be a RUD.

While it is possible that there were multiple events, I see no reason why they might not both be referring to the same event in different ways.

[insert_name]

COPV from Falcon upper stage recovered from Washington state

 

[CatastrophicFailure]

4 minutes ago, insert_name said:

COPV from Falcon upper stage recovered from Washington state

Aw man.  So close. 

relatively...

[Lewie]

Oh, the Falcon 9 upper stage is pressure fed? Huh. I knew krestel was, but not the V-Merlin.

[insert_name]

7 minutes ago, Lewie said:

Oh, the Falcon 9 upper stage is pressure fed? Huh. I knew krestel was, but not the V-Merlin.

No, it uses a turbopump as well, even non-pressure fed engines need to have some sort of pressurization mechanism, or this could have been for the cold gas RCS

[kerbiloid]

The crater 

https://www.theverge.com/2021/4/2/22364582/spacex-rocket-debris-falls-farm-washington