I suspect that Starship will fly to space before SLS ever will. I also think Starship has a significantly higher chance of flying at all than SLS.
Starship Prototype Unveiled
31–40 of 342 posts
Re: Starship Prototype Unveiled
#32The SpaceX/Musk presentation video: https://www.youtube.com/watch?v=sOpMrVnjYeY
Re: Starship Prototype Unveiled
#33I suspect that Starship will fly to space before SLS ever will. I also think Starship has a significantly higher chance of flying at all than SLS.
Starship could have Falcon Heavy level of delays (which I think it will) and still beat SLS.
Re: Starship Prototype Unveiled
#34I totally understand why they've gone for that design but the welded together steel plates really make me think of the sort of thing Wallace and Gromit would build.
he addressed in presentation, from what i remember it had a lot to do with cost. Like $130k/ton with carbon vs $3k/ton with steel. He mentioned a few other factors. Also it allowed them to build outside, not sure if t that is true in production.
the material isn't the question, it's why they had to weld it together in a patchwork quilt. Elon talked about the next version would simply have rolled coils with a single seam weld (although the cylinders would have to be welded together too), which would be better structurally and cosmetically, and likely lower cost of production. Sounds like they just didn't have the rolling machines to do the job, or perhaps there was an availability issue with the specific alloy.
Re: Starship Prototype Unveiled
#35380s for ISP for the Raptor vacuum engine seems durn good, considering the tradeoffs between hydrogen and methane. The most efficient engines we've flown, the RL-10 [0] (used on the Delta IV and Atlas rockets as part of the Centaur Upper Stage) and the RS-25 [1], (the Space Shuttle Main Engine) get around 450-460s for their specific impulse. These engines use liquid hydrogen and liquid oxygen. The issue with liquid h…
Here's a Wired article about the raptor engine - it's "a full-flow staged combustion engine, only the third engine in history to employ this technique ... The previous two attempts at such an engine, one in the Soviet Union in the 1960s and another in the US in the early 2000s, never made it beyond testing." https://www.wired.co.uk/article/spacex-raptor-engine-starshi...
I'm sorry but did anyone do a rudimentary spelling and grammar check on that?
"Raptor is designed to power the new reusable vehicles SpaceX’s is building, the Starship spacecraft and the Super Heavy rocket."
Also they call Tim Dodd an "industry expert"...
Re: Starship Prototype Unveiled
#36380s for ISP for the Raptor vacuum engine seems durn good, considering the tradeoffs between hydrogen and methane. The most efficient engines we've flown, the RL-10 [0] (used on the Delta IV and Atlas rockets as part of the Centaur Upper Stage) and the RS-25 [1], (the Space Shuttle Main Engine) get around 450-460s for their specific impulse. These engines use liquid hydrogen and liquid oxygen. The issue with liquid h…
Here's a Wired article about the raptor engine - it's "a full-flow staged combustion engine, only the third engine in history to employ this technique ... The previous two attempts at such an engine, one in the Soviet Union in the 1960s and another in the US in the early 2000s, never made it beyond testing." https://www.wired.co.uk/article/spacex-raptor-engine-starshi...
And if you want to get a lot more detail on what makes a "full flow staged combustion engine" so special, this article from Everyday Astronaut goes into some amazing detail on this and many other engines.
Re: Starship Prototype Unveiled
#37380s for ISP for the Raptor vacuum engine seems durn good, considering the tradeoffs between hydrogen and methane. The most efficient engines we've flown, the RL-10 [0] (used on the Delta IV and Atlas rockets as part of the Centaur Upper Stage) and the RS-25 [1], (the Space Shuttle Main Engine) get around 450-460s for their specific impulse. These engines use liquid hydrogen and liquid oxygen. The issue with liquid h…
https://youtu.be/Sdwy9fzQzl4 Scott Manley does a great job explaining such things!
I'm surprised the guy being a youtuber. He is the codecs guy at Apple Computers
Re: Starship Prototype Unveiled
#38I suspect that Starship will fly to space before SLS ever will. I also think Starship has a significantly higher chance of flying at all than SLS.
Starship could have Falcon Heavy level of delays (which I think it will) and still beat SLS.
Not entirely sure about that. Have no skin in the game but from what I can tell Starship is just a bigger version of the Falcon 9 second stage. FH on the other hand required a lot of engineering investment to figure out how to bolt three F9s together and how to make the software work between all three.
I'm certain it will be a long time until it can get to Mars, but LEO within the next 2-3 years is probably realistic.
Re: Starship Prototype Unveiled
#39I would love to know what the "Day-in-the-life" of a welder working on those ships would be. Did they train specifically for aerospace welding? How did they land that specific gig. Must be so inspiring to wake up and work on that.
A good weld on 301 steel isn't very different regardless the purpose.
and welds are very testable via x-ray (perhaps some other techniques), and I believe repairable unless someone really screws up.
Re: Starship Prototype Unveiled
#40Earlier quoted context omitted.
he addressed in presentation, from what i remember it had a lot to do with cost. Like $130k/ton with carbon vs $3k/ton with steel. He mentioned a few other factors. Also it allowed them to build outside, not sure if t that is true in production.
the material isn't the question, it's why they had to weld it together in a patchwork quilt. Elon talked about the next version would simply have rolled coils with a single seam weld (although the cylinders would have to be welded together too), which would be better structurally and cosmetically, and likely lower cost of production. Sounds like they just didn't have the rolling machines to do the job, or perhaps the…
It will reduce the length of the welds (for the hull) quite a bit.
The number of rings is roughly 35 for Starship, with about ten vertical seams each.
For easier thinking, line the vertical seams up and you see that this gives 50m length per vertical seam from bottom to top of Starship. So there are a total of 500m for that.
35 rings with ~28m circumference add up to about 1km of seams between them.
Now if they can use rolls twice as wide and only a single vertical weld each, then that's 500m between the rings and 50m for a single vertical seam. 550m of welds there instead of 1.5m before. This should speed things up quite a lot and reduce the cost of labour.
Raptor production is the real bottleneck, though.