If you’re reading this, there’s a very good chance you’ve seen this famous image of three iterations of SpaceX’s Raptor rocket engine.
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Everything in the manufacturing process is also challenged to justify its existence.
This is how he managed to reduce the costs by 90%.
Isaacson’s “biographies” are glorified puff pieces. Musk is as unrecognizable in his as Jobs was in his.
Both Tesla and SpaceX had teams keeping Musk busy on bs just so that the engineering teams could do their work.
The second he took control, we got the cybertruck and the starship, the worse products both companies ever built (or attempted, in the case of the starship).
> Musk relentlessly challenges the existence of every part
This sounds insightful until you find yourself debating with the CEO for the eleventh time about how his high-school understanding of the physics involved breaks down in a particular case.
Musk is very lucky to be moving such quantities of money that his companies are big enough to protect themselves from him, if you ever wonder how Musk would fare on a tight budget, look no further than the Oceangate.
"This sounds insightful until you find yourself debating with the CEO for the eleventh time about how his high-school understanding of the physics involved breaks down in a particular case"
Musk has a bachelor's degree in physics from the University of Pennsylvania. While not a full scientist, I doubt that "his high-school understanding of the physics involved breaks down" anytime often.
Have you ever been in such a situation that you describe, or is this just your prejudice speaking? AFAIK the discussions in SpaceX revolve more around things like "can this part be 3d-printed", "do we keep the actuators for part X or can it just stick out into the wind" or "should we use landing legs or not", which have nothing to do with high-school physics and everything to do with actual engineering tradeoffs.
"the starship, the worse products both companies ever built (or attempted, in the case of the starship)."
This is what tells me that you are speaking in bad faith. Starship is not yet a finished product. Judging it now makes about as sense as judging Edison's lightbulb a year before it was introduced into the market.
Starship has several issues to fix, but we can already see that a) the Raptor engines are about the best on the planet, doubly so when considering their extremely low unit cost; b) the vessel itself is very tough and performed well even in really bad situations; c) the heat shield developed a lot and the last Starship (the one which was dragged to the Christmas Island) survived reentry in very good condition; d) the amount of control (belly flops, slowing down to hover) that they have over that huge thing is unique in the history of spaceflight.
Regardless your thoughts on Elon, his drug habits, and his political brashness, I don’t think you can say he’s in any way close to the Oceangate guy. There is something legitimately special about him and his collective.
On Falcon 1 and 9 he worked directly on major components of the vehicles.
In Tesla, he was heavily involved in the design of every single product they came out with. He also micromanaged Model 3 assembly automation in 2017-18.
This removal of surplus-age is common in the automotive industry, and one of the reasons that cars are such an amazing value. It seems like Musk's remarkable ability to achieve cost reductions (at least in the aerospace context) is attributable to his pursuit of vertical integration. Airframers (aeronautical vehicle designers & manufacturer) are bound by the costs dictated by their component suppliers, especially after a configuration has achieved regulatory approval. SpaceX has managed to avoid being 'held hostage' by pseudo-monopoly suppliers.
I will not attempt to break all the reasons for SpaceX success in this post, but its certainty more complex then just vertical integration. And vertical integration isn't absolute, in some cases they reversed their vertical integration again.
Team building by Musk, consistent having engineers work on hard project after hard project, willing to invest in a next generation even if the existing system works in the current market context (canalizing yourself), believing in increasing scale overtime (only when planning to build 100s of engine iteration makes sense) are just some of the relevant parts of SpaceX success as an organization.
People claiming Musk has nothing to with this or is just some irrelevant figurehead money guy are idiots. At the same time, the brilliance of the team he build ultimately is far more important then his own suggestion about ideas with engines.
In case of the engine its actually Tom Mueller who basically off hand suggested to him that to reach his goals, he would have to design something nobody had ever done on a large engine, and was only used for smaller engines (phase shut off). Musk jumped on that and imitatively said that this is what they should do. Mueller said he wasn't sure if it could be done, but since they knew of no other way to achieve the goals, the team went off and eventually achieved it.
Mueller himself said he thought going after this was a mistake and a less aggressive simplification should have been done, but said he proved himself wrong and it was a massively important innovation.
This shows some important aspects of Musk. Not that he is some genius that magically design an amazing engine. Rather that he listened to his engineers and gave them the finances and confidence that they could achieve outlandish targets, and continued to support them even if they couldn't hit the target instantly. We see this again with Raptor, they had a target in mind and followed every line of design to achieve something close to as good as a 2 fuel engine is going to get.
One can argue that this is just blind optimism and then throwing money at the engineers, and that is certainty partly a fair critic of this approach. It did not work with self driving in the same way at Tesla. But the difference is that with evolution of Merlin and Raptor he listen to engineers who proposed challenging ideas that were still iterative and he supported them.
I have followed Space for a long time. Musk isn't some magical unique genius, but he certainty isn't do nothing idiot some of his haters want us to believe.
SpaceX success deserve series study and SpaceX without Musk is basically really understandable as an institution.
Elon's strength is his willingness to pull the plug and transition away from suboptimal solutions. This is bolstered by his willingness to double down.
Imagine if Boeing said "screw all this recertification technical debt for the 737 MAX airframe, we will start fresh. Customers can take it or leave it"
You say that and then a company like Ford releases this as their EV to show the world that they are competitive with Tesla.
[1]: https://youtu.be/C1dQtlrI7uU?t=70
How does something like this happen despite Ford knowing all the 'secrets' a company like Tesla or the Chinese know? I have a few guesses:
1. Its the structure of the company. In this video the presenter talks a lot about all the hoses and clamp connectors etc. The cooling department thinking they had to stay relevant made sure the car incorporated a design that had all this nonsense.
2. Maybe they didn't put their 'A' engineers on this car. Its plausible: the F-150 is their massive money maker. However this car was supposedly developed under some skunkworks program and yet here we are.
3. Maybe there was sabatoge from elsewhere (suppliers, middle management etc.) You watch a movie like Ford vs Ferrari and while im sure a lot is dramatized, I can't help but think man they were talking about the dysfunction of Ford way back then?!
Then we have Youtube documentaries like this one about the Ford Taurus SHO talking about how they screwed up so much that they had one chance left to get serious...like what? Shouldn't they be serious every day? Thats what the Chinese are doing.
[2]: https://youtu.be/5VTRhCC3gZI?t=56
The presenter further added how they had to ship entire engine blocks to Japan so that they could 'fix' them and unlock 80 more horsepower that Ford just left on the table. If factual, this should be a total embarrassment: You had to send your handiwork to a entity with a better reputation so that they could 'fix' your mess?
[3]: https://youtu.be/5VTRhCC3gZI?t=212
At some point, you have to acknowledge that the naysayers were wrong: Thinking (especially among the short community) was that Tesla had some cool ideas but their implementation was horrific, they couldn't just make up for 100+ years of institutional knowledge that the legacy companies had. The Tesla cars showed some of this thinking: quite poor build quality, poor after sale support, poor parts network. These things improved over the years but still isn't perfect.
But at the same time you have to acknowledge that the legacies suffer from their own problems that dont put them as far ahead as newcomers as you'd think. Sometimes a lot of that institutional knowledge becomes a liability when a paradigm shift occurs.
You win some, you lose some.
Raptors can be used without TVC. Be that by using differential thrust, or just not needing that - because rocket is controlled using other means, or other engines - it's possible. Tory Bruno specifically explained that he meant - among other things - that absence.
A picture of the engine working on the test stand can be that for the engine - or for the chamber, a significant component of the engine, with or without turbopumps involved.
In addition, SpaceX isn’t cheating by not including TVCs. They purposely designed their rocket to need a minimum of them and fully take advantage of the space savings the lack of TVCs affords them.
[1] “So, there is no need to exaggerate this by showing a partially assembled engine without controllers, fluid management, or TVC systems, then comparing it to fully assembled engines that do.”
And if you see Raptor integrated on Starship you can see this clearly.
From the article links, I am amused that SpaceX uses cybertrucks to tow their rocket engines around the grounds and not a normal cheaper truck. They also do it in a totally uncovered trailer, which must be good for the guys taking pictures for forums. But isn't that also good for guys taking pictures for competitors / Russians/ China?
This hasn't been true for over a decade. High value relative to weight, highly complicated internal geometry, or repeated need for one off parts are all reasons to choose 3d printing today for production parts.
If they buy $131M worth of Cybertrucks[1], they might as well use it for something...
[1] https://www.businessinsider.com/spacex-bought-tesla-cybertru...
https://newsroom.bugatti.com/en/press-releases/bugatti-refin...
Also subtractive manufacturing requires paying to melt away a lot of metal. 3D printing saves.
I don't know all of the ways in which SpaceX is using
And several engines failed to relight on the booster for flight 13. I believe ice in feed lines is viewed as the most likely cause.
Isn't the Space shuttle main engine / SLS engine a full-flow staged combustion engine?
The SSME uses the same kind of fuel-rich combustion chambers for both preburners. This presents a problem for the oxidizer side because any leaking along the shaft between ox pump and turbine in either direction would be catastrophic. This is resolved by an extremely expensive and complex multi-stage helium-purged rotating seal.
One of the cool parts about most FFSC designs, and the raptor in particular, is that they can afford slight leaking from high pressure to low pressure through any seal in the system and it's broadly safe, and only marginally reduces performance. This allows them to be made much more cheaply.
I think China has made a full flow engine too.
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