[gridspy]

The shuttle boosters required rebuilding / refueling (which is solid rocket goop) and the fuel tank was completely lost and required rebuilding. The head shield tiles were extremely fragile on the shuttle.

It was never a fully reusable design, just more reusable than before.

SpaceX plans to have no parts that are lost each flight and is working to make the tiles mostly standardized and less sensitive to faults.

[trompetenaccoun]

Are they going to replace all the tiles before it can relaunch? And what about the engine nozzles? They must be taking quite the beating.

No doubt SpaceX has very smart people working on this and I'm not an expert in material science, but I just find it hard to believe that same day turnaround could be possible. If true, that would really make us a confirmed space faring civilization. We could actually start colonizing Mars.

[wongarsu]

The heat tiles are reusable, just like the Shuttle's. They are basically just a material that insulates very well, instead of a traditional ablative heat shield that burns away. With the space shuttle they ended up spending a lot of time inspecting each tile for damage and replacing cracked tiles. SpaceX has a modern iteration of the same material, hopefully with fewer cracks.

Other factors that work in SpaceX's favor are 1) that most launches will be unmanned, meaning they can take bigger risks than the Space Shuttle program; 2) that the steel body of Starship can handle higher temperatures than the Space Shuttle's aluminum, so a compromised heat shield is more tolerable; 3) for now they have a secondary ablative heat shield below the tiles (that does have to be replaced when it gets used, but that should only happen when tiles fall off)

[dr_orpheus]

For context on JumpCrisscross's comment in this thread: the 4 hours is between two separate launches on two separate rockets. This is absolutely not refurbishing and launching the same rocket 4 hours apart.

Seems like the actual record for turning around the same booster is 21 days, which is still quite impressive.

https://www.teslarati.com/spacex-falcon-9-new-booster-turnar...

[JumpCrisscross]

> what about the engine nozzles?

Falcon 9 has reflown in just over 4 hours [1]. (EDIT: Operational turnaround. Nozzles have been turned around allegedly without refurb in 3 weeks.)

[1] https://en.m.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_...

[ceejayoz]

No, those were separate craft, on opposite sides of the country. It demonstrates an ability to manage multiple missions at once, but not rapid booster turnaround.

https://www.space.com/spacex-starlink-launch-doubleheader-ju...

They've since done two flights in about an hour with https://spaceflightnow.com/tag/starlink-9-5/ and https://spaceflightnow.com/tag/starlink-8-10/

I think the first-stage turnaround record is something like two weeks.

https://en.wikipedia.org/wiki/List_of_Falcon_9_first-stage_b...

> B1062 booster holds the record for fastest turnaround at 21 days. It launched on 8 April and again on 29 April 2022.

[seadan83]

Beware the dunning-kruger effect. There is a lot more to colonizing mars than reusable rockets. Just saying..