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I'm having difficulty understanding how/if Starship and/or Super Heavy could be used to deliver crew to LEO.

Is it expected to deliver astronauts to the ISS Crew-Dragon-style, but without the 2nd stage; that is, "FSTO"? (as opposed to SSTO)

If no, can the Super Heavy be made into an SSTO spaceship, capable of ISS docking and vertical landing?

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    $\begingroup$ Several issues: what you are calling "FSTO" seems to be what is generally called SSTO. Second, the Crew Dragon is not SSTO, so it's unclear how that can be "Crew-Dragon-style". Third, the second half of your question jumps to asking about the Superheavy, which is the booster. Also, SSTO capabilities of Starship have been asked about before, does space.stackexchange.com/a/39275/15771 answer your questions? (And aside from all that, Starship is not currently planned to be used in ISS operations.) $\endgroup$ – Christopher James Huff Apr 10 at 22:26
  • $\begingroup$ @ChristopherJamesHuff I like the newly-coined "First Stage to Orbit" or FSTO. :-) Concern about Dragon and other terminology been addressed by adjusting the wording slightly. I've been quite puzzled by the same question that the OP asks so I hope an answer can be posted. $\endgroup$ – uhoh Apr 11 at 0:07
  • $\begingroup$ What could "Crew-Dragon-style" even mean in this context? A SSTO crew transfer vehicle wouldn't have any more in common with Crew Dragon than any other spacecraft. The question's basically saying "like Crew Dragon, except different in almost every detail". $\endgroup$ – Christopher James Huff Apr 11 at 12:43
  • $\begingroup$ @ChristopherJamesHuff no it is not basically saying that, it's saying what's written in the post. My guess is that it simply means "capsule style" where it docs, opens a hole, and people crawl through. $\endgroup$ – uhoh Apr 11 at 20:10
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    $\begingroup$ I wonder if OP is not using “SSTO” for “Second Stage To Orbit” when most people use it for “Single Stage To Orbit” which is nearly exactly the opposite? That would explain part of the confusion... $\endgroup$ – jcaron Apr 12 at 8:05
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Is Starship planned to fly directly to the ISS without first stage?
Is it expected to deliver astronauts to the ISS Crew-Dragon-style, but without the 2nd stage; that is, "FSTO"?

No. Starship will be launched on top of Super Heavy. There is no plans for a SSTO Starship on Earth to carry crew/cargo to orbit.

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Is it even possible?

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Tweet. You would have to launch Starship without recovery equipment to do SSTO; meaning no recovery, which for crew transportation to LEO; is problematic to say the the least.

If no, can the Super Heavy be made into an SSTO spaceship, capable of ISS docking and vertical landing?

Probably not. The mass margins just aren't there for a methalox FFSC rocket. With something like Skylon you could, but of course that's using an advanced air breathing hydrolox engine.

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  • $\begingroup$ Thanks for straightening this all out. I didn't really have a clear picture of what could or couldn't be done. $\endgroup$ – uhoh Apr 11 at 20:11
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Is it expected to deliver astronauts to the ISS Crew-Dragon-style, but without the 2nd stage; that is, "FSTO"? (as opposed to SSTO)

Starship cannot get to orbit in any meaningful way without Super Heavy. Theoretically, it would be possible to get to LEO without any payload and by removing all recovery hardware, the body flaps, the landing legs, the heat shield, the header tanks, and the extra fuel for landing. However, doing so wouldn't make any sense.

You need Super Heavy to do anything meaningful … such as bringing crew to the ISS.

If no, can the Super Heavy be made into an SSTO spaceship, capable of ISS docking and vertical landing?

Super Heavy is the booster. It can't get to orbit. And if by some miracle a Super Heavy magically gets transported into orbit, then it can't get back: it has no heat shield, no way to shed its velocity, no way to survive reentry from orbital velocity.

It doesn't really make sense to compare Starship to capsule-based systems such as Dragon, Soyuz, Starliner, Orion, or Apollo. You should compare it to the Space Shuttle.

Starship works very much like the Space Shuttle in that it "merges" the traditionally separate second stage and crew vehicle into a single vehicle. There are only two stages: Super Heavy, which is the booster, and Starship, which is both the second stage and the "capsule". Unlike the Space Shuttle, it will not throw away its tanks.

Starship docked to the ISS will look pretty ridiculous, though:Starship docked to the ISS[Source: SpaceX]

Starship's pressurized volume is comparable in size to the pressurized volume of the entire ISS – this means that a single Starship launch will bring as much habitable space into orbit as 12.5 years of construction on the ISS!

However, note that despite the renders on the SpaceX website, there are currently no plans to actually use Starship to launch to the ISS. Also, it is going to be a long time until Starship gets crew-rated as well as certified for ISS proximity operations.

In fact, it is questionable whether that even makes sense: why go through all the hassle of docking to the ISS, unloading all the crew and cargo and the experiments, install all the experiments on the ISS, then after 6 months un-install all the experiments, load everything back into Starship, etc. when Starship is so big and so cheap that you can just use it as the space station?

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  • $\begingroup$ I'm shuddering at the amount of integration work that would be necessary to get that combination approved. Docking loads alone would be quite the beast. $\endgroup$ – Tristan Apr 12 at 17:45
  • $\begingroup$ It's not even obvious to me who is docking to whom :-D $\endgroup$ – Jörg W Mittag Apr 12 at 18:27
  • $\begingroup$ I think it becomes a mutual affair at some point $\endgroup$ – Tristan Apr 12 at 18:29

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