The post mentions an expendable version at 15m d but that can't be done on either the current iteration (9m) or v2.0 (12m). The original plan was for 15m but that would require around 100 raptors to get it off the ground!
We should expect to see a bunch of alternative configurations for Starship. A big fairing is just one possibility.
On Falcon, and in the future with conventional Starship, Starlink launches are volume-limited, not mass-limited. Thus, a Starship with more interior space would allow them to send up many more satellites per launch.
When they get their production line up, we might see them launch Starlink in disposable second stages, dispensing with heat shielding and landing engines, and with substantially smaller fuel tanks, leaving room for more Starlink cargo. They could park the carriers in orbit, and gather up the Raptor engines to bring home once enough have piled up there; and maybe turn the empty hulls into a fuel depot.
Launching, say, 150 satellites at a time, that's more than a hundred launches to fill out the constellation. It should not be hard to find a use for some fraction of those hulls given they have already been boosted to orbit.
They'd need a stage0 systems built specifically to support a 15m large fairing. I'm not saying this will never happen, I just don't think it will be on the cards for a long time, if at all. Basing things around 9m/12m may be a better idea if they want to get something in the sky sooner, rather than later.
I am thinking now that if they want Starlink to be a demonstrator for their freight service, they will more likely eat the cost of launching on non-customized vehicles, and of landing, refurbishing, and re-using them, instead of leaving them in orbit.
You'd need to build an entirely new stage0 system. How would a 15m fairing fit onto the current orbital launch pad?
Not saying it can't be done, just that it's not as simple as just whacking a larger fairing on, there are lots of considerarations to deal with. Perhaps it's worth it for 15m, but then again even a 9m would be a vast improvement from 2.4m
> For a relatively trivial fraction of the overall telescope budget, non-recurring engineering costs could weld together an expendable Starship variant (no TPS, no flaps, no landing legs) with a 15 meter diameter payload fairing. Almost overnight, endless gnashing of teeth about the relative mirror diameters of Luvoir or Habex, or the relative difficulty of performing coronography with a segmented, non circular mirror, go away.
As I've noted in other replies, you'd need an entire new stage0 to accomodate this. Even larger than the 2.0 planned. It'd be have to be made especially for this.
> The post mentions an expendable version at 15m d but that can't be done on either the current iteration (9m) or v2.0 (12m). The original plan was for 15m but that would require around 100 raptors to get it off the ground!
However, that's not obviously true. This is just a fairing. The fairing can be made wider w/o adding engines or making the booster (or the bottom of starship) wider.
Then you mentioned the stage zero issues, but if an expendable starship with a wider fairing doesn't need to be reused then there's plenty of space right now between starship's nose and the launch tower for a wider fairing, and a crane can be used to stack it instead of the chopsticks if the wider fairing makes using the chopsticks impossible. Even if modifications to stage 0 are needed -or a new one altogether-, if SpaceX ends up building more stage zeros elsewhere (like, say, at Cape Canaveral), they'll have a chance to accommodate larger fairings then.
Certainly. First things first. They have a year's worth of testing ahead of them just to make 100t to LEO reusable launch vehicle a thing. Once they've done that they'll be able to build a new stage zero, work on larger and smaller launch vehicles (smaller because why let others take the by then obsolete Falcon 9's business?) (larger only for large telescopes and such).
Did you read the same post I did? TFA talks about a "15 meter diameter payload fairing". I don't see why Starship couldn't do that. Full quote:
> For a relatively trivial fraction of the overall telescope budget, non-recurring engineering costs could weld together an expendable Starship variant (no TPS, no flaps, no landing legs) with a 15 meter diameter payload fairing. Almost overnight, endless gnashing of teeth about the relative mirror diameters of Luvoir or Habex, or the relative difficulty of performing coronography with a segmented, non circular mirror, go away.
I've never heard it mentioned by anyone working at SpaceX or any commentators (bar this person, it seems).
You'd have to build an entire new stage0 system, for starters, even if you've built a new one for starship 2.0 as it wouldn't accomodate the larger fairing size.
Considering it took them roughly 2 years to develope Starship from scratch, even if that's the case, it would still be an order of magnitude lower cost than anything else, wouldn't it?
