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I much prefer their design to starship. It's optimising for the hardest part of the trip: re-entry.. Also re-entering like Apollo and not like the space shuttle is a good thing imo. It doesnt rely on an ablative heat shield or tiles, also it doesnt have extremely heavy / complex / vulnerable actuated fins yet it can get lift and steer itself simply with it's shape and by rotating the whole craft like Apollo.

SpaceX is a mix of mindblowing engineering with sometimes baffling decisions. I can never help but wonder how much input Elon has, and if he is responsible for all those questionable choices, as he honestly appears to be a bit of an idiot.

I've been following Starship's development avidly, but knowing he's involved always makes me cringe a little.

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> SpaceX is a mix of mindblowing engineering with sometimes baffling decisions. I can never help but wonder how much input Elon has, and if he is responsible for all those questionable choices, as he honestly appears to be a bit of a idiot.

Let me get this straight. You believe that Stoke space is somehow the near perfect design. The designer or Shuttle and Starship were probably idiots for not coming up with the same ideas as Stoke. But maybe the reason that they are so dumb, is simply because Musk is part of the design team.

Maybe you should consider, just maybe, that if Starship isn't exactly like Stoke spaces design, it could have actual reasons. Maybe, just maybe the most successful rocket company in history had actual technical reason for their design choices. But no that couldn't be it, could it?

But instead of asking the saying 'Stoke Space design seems really awesome, I wonder why SpaceX made difference choices', you just jumped to 'well Musk is cringe and therefore that must be the reason'.

"You believe that Stoke space is somehow the near perfect design"

- I said I much prefer it to starship, not that it's near perfect.

"The designer or Shuttle and Starship were probably idiots"

- I dont know much about the design of Starship, that stuff is not in the public domain atm. But the space shuttle designers were not idiots, they just had to deal with some impossible requirements from higher up. The space shuttle as-built has some clearly bad design elements (eg. the shuttle itself not being on top of the stack at launch, as it was in the original design). It had a famously long and torturous design process with many different stakeholders all wanting it to be capable of wildly different missions. Just one example: https://youtu.be/_q2i0eu35aY?feature=shared

So one could say management meddling with the design is what killed the space shuttle. I am wondering is the same meddling happening in SpaceX?

Starship famously has one mandated mission: colonizing Mars. Most design decisions revolve around it.

On Musk making Starship decisions: "Elon’s direct engineering management style may help him maintain alignment between Mars-oriented designs and the greater defense-oriented requirements of an SDI system"

https://grook.ai/saved_session?id=e269e88a7b1a71eff4f176c864...

Im just baffled that you seem uninterested in actually consider technical reasons of why Starship is not the same as Stoke space. The only thing you seem to wonder about if it is managment meddling.

Of course we dont know exactly why each decition was taken, but there are some pretty clear technical reasons that one could think about before using 'cringe' as an explnaition.

Let me answer that for you: it's well-documented and confirmed by many insiders, including Tom Mueller and Gwynne Shotwell, that a) Musk has always had a lot of technical input, and b) he is responsible for the good choices that made SpaceX into what it is today.

Of course the truth falls afoul of the "Musk is evil now" memo mentioned downthread, so you keep believing what you believe.

It fascinates me how people can turn "Musk has a toxic personality" into "Musk can only be the money man, must be stupid, and cannot have any technical skills." As if the tech industry hasn't already had a proud tradition of brilliant asshole CEOs named Jobs, Gates, Zuckerberg, and Ellison just to name a few.

Being an asshole isn't required for success, but it unfortunately also doesn't necessarily inhibit it either.

This comment is an excellent example of ideology superseding real world results.

Just an incredible public display of cognitive dissonance.

Hey, we all received the memo - Musk is evil now. So please, play your part.

All jokes aside - having different implementations/ideas competing for similar goals is nothing but good. We cannot pretend to have "min-maxed" space travel or rocketry at this point in time - so there's still lots of ideas to experiment with.

Any organization that can successfully design, assemble, test, and launch a new rocket into space is a huge victory for the US, space exploration, and ultimately the world. Making space more accessible is likely to lead to all kinds of new discoveries and technology that benefits earth and beyond.

Starship is still in development and is running into significant delays and they have yet to show even a depot, tanker and lunar lander mockup. What real world results are you talking about? It is not like the current version of starship could deploy a payload because they removed the payload doors to make reentry easier. The last test flight took many steps back to test upper stage reuse, which is a capability that won't be needed any time soon and could have been tested in parallel with other changes. Sure, with every test they are incrementally developing the rocket, but from my perspective the progress between launches is the same as if they hadn't done any test launches. There is no magical development speedup coming from their approach, mostly because they are taking many detours. The attempt to launch without a deluge system was just a waste of time and their first rocket. They could be moving faster, but they don't.

"It's optimising for the hardest part of the trip: re-entry."

Is it really the hardest part?

I would say that for fully reusable rockets, the hardest part is quick turnaround. For future space activities, it will be a huge economic difference if you can send the ship back in, say, 12 hours vs. 120 hours.

I agree with this, I may have said the same thing.. But I was thinking that the tech used for re-entry is what tends to increase the turnaround time (Eg. ablative heat shields, tiles). Making something that's rapidly re-usable which can also withstand re-entry from orbital speeds is probably the greatest challenge in this domain.

The shuttle was originally envisaged to be cheap and rapidly re-usable for the time. As built it didnt turn out that way, it would have been overall cheaper and probably faster to launch a fully un-reusable rocket than a shuttle.

Yeah, my guess is that quick turnaround is a function of mainly two variables: a good protection of the ship during re-entry and very reliable engines that require little to none manual checking and can withstand lower thousands of cycles before needing refurbishment.

Of those two, I am fairly sure that SpaceX can produce great engines. The Raptors are not quite there yet, but their 4th or 5th iteration will likely be extremely good.

Not so sure about the heat shields. Much less aggregated corporate experience there.

It was quickly taken down, but there was a video on YouTube from someone who got hold both of a Space Shuttle and a Starship heat shield tile. He analyzed it with a microscope. He found that the material was nearly identical. I do wonder why SpaceX thinks they can make a ceramic heat shield work when it needed lots of checks and refurbishment for the Space Shuttle. Recently Musk even said they will add an ablative heat shield in certain areas.

On the other hand, the at least the reusability of the lower stage shouldn't be a problem.

There are quite a large number of parameters other than the material, surely. The whole design is different.

Not at all. The tiles just consists of two layers. The main body and the dark layer on top. According to the electron microscope analysis, the two tiles were mostly the same.

I mean more, the size and shape of the ship, the size/shape/thickness of the tiles, the attachment method, the substrate material, the flight profile...

I'm not seeing where SpaceX could have achieved a major innovation here that solves the problems the Space Shuttle had with the heat shield. I think the latter used glue rather than pins, but probably not because the Space Shuttle people couldn't make pins. If it was that easy...

Those details could affect the heat flux and temperatures the material is exposed to. The two spacecraft have very different designs.

I guess one advantage of SpaceX compared to NASA is that the former are very trial and error based in their design, so they can iterate much more. NASA tends to design and plan everything in advance and only build it at the end. So when the Space Shuttle reusability didn't quite pan out, they couldn't easily change things up.

From what I understand, they are trying to keep their unique type shape count very low relative to the shuttle, which should make tile replacement a lot cheaper. Nonetheless, the tiles seem like the weakest aspect of the whole design. Recall that the early proposals didn't have tiles at all, so the tiles existing now is already and acknowledgement that not everything is going according to the ideal path.

I wonder whether they considered using a metallic heat shield with heat resistant alloys. The cancelled VentureStar space plane was planned to use this approach:

https://ntrs.nasa.gov/api/citations/20040095922/downloads/20...

They were originally hoping to use transpiration cooling, the tiles ended up being the fallback.

Yeah, but it isn't clear whether they ever considered a metallic heat shield. At some point in the past it was considered an improvement over ceramic tiles, since the VentureStar was planned as a Space Shuttle successor that fixed its shortcomings.

To add & also imo, it's probably good thing that it's not designed to mimic old stuffs. Biplanes with train car fuselages and automobiles with horse carriage aesthetics went out of fashion quick. Space transport systems with a cargo plane design didn't work all that well too.

Meanwhile, if we look at Apollo style reentry, it just works. From first time and every time and even for interplanetary entries. Clearly that's something that isn't broken and not in need of a fix.

Blue Origin was founded before SpaceX by a rich guy that had far more money than Elon Musk did. To cringe at SpaceX leadership is idiotic; the leadership is what made the difference between a company that has dominated the space industry (putting even every single national program around the world combined to shame) and one that has never put a single object into orbit.

Not money. Not timing. Not even the engineers, because Blue Origin had every opportunity to hire the best. It was the leadership.

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