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SLS flew around the moon and back on the first try.

stetrain 3y ago
Using a large number of existing flight tested components and construction techniques that have been in production since the 70's. And with a cost and construction time that limits it to around 1 launch per year going forward at $4b per launch, optimistically. SLS can theoretically launch 100T to LEO. Starship can theoretically launch 150T reusable, 250T expendable. Construction rate is already on the order of around one per month, although obviously they are working out issues with the launch infrastructure to actually be able to make that many launch attempts.
- 2OEH8eoCRo0 3y ago
  Irrelevant. My point was that you can essentially prove the design is sound before you even build the thing. Rapid failure/iteration is not the only way to build rockets.
  - avmich 3y ago
    "Can" doesn't mean you "should", and for such a price it's a doubtful proposition.
  - s1artibartfast 3y ago
    >My point was that you can essentially prove the design is sound before you even build the thing That depends on your design and if you need experimentally derived inputs
  - throwaway4aday 3y ago
    Not if you're using new engines, new fuel systems, new heat shielding, new materials for the body, and making both the booster and second stage fully reusable by landing them with the help of a never before tried system that catches them before they touch the ground.
  - stetrain 3y ago
    NASA has blown up a lot of RS-25s over decades in testing to get to that point. And a couple of Shuttles. When half your components have decades of reliability under their belt of course it’s easier to have a successful first launch. If your development methodology results in a product that is unsustainable to launch due to costs and scalability, that absolutely seems relevant to whether that methodology was successful.
brandonagr2 3y ago
While shamefully chucking RS-25s into the ocean
- 2OEH8eoCRo0 3y ago
  And Starship blew up 39 raptor engines, and will probably blow up another 39 tomorrow.
  - DarmokJalad1701 3y ago
    At least blowing up the raptor engines isn't the planned operational design. Even if they blow up 39 tomorrow, an operational Starship/Superheavy will not do that. That's the whole point. SLS is going to be tossing four RS-25 engines per launch (with *each* engine costing the same as ~2-3 entire Falcon 9 launches) into the ocean as the planned course of action. That is by design - and not some accident during a test flight.
  - throwaway4aday 3y ago
    Rocketry advances one explosion at a time.
- nordsieck 3y ago
  People keep saying that. I don't really understand why. Sure, RS-25s were designed to be reusable. But it's not like they were being used for anything; they were just hanging out in a warehouse since the Shuttle days. If NASA was going to put them in a museum or something it would have already happened. At least this way, they get used for what they were designed for.

Using a large number of existing flight tested components and construction techniques that have been in production since the 70's. And with a cost and construction time that limits it to around 1 launch per year going forward at $4b per launch, optimistically. SLS can theoretically launch 100T to LEO. Starship can theoretically launch 150T reusable, 250T expendable. Construction rate is already on the order of around one per month, although obviously they are working out issues with the launch infrastructure to actually be able to make that many launch attempts.

2OEH8eoCRo0 3y ago
Irrelevant. My point was that you can essentially prove the design is sound before you even build the thing. Rapid failure/iteration is not the only way to build rockets.
- avmich 3y ago
  "Can" doesn't mean you "should", and for such a price it's a doubtful proposition.
- s1artibartfast 3y ago
  >My point was that you can essentially prove the design is sound before you even build the thing That depends on your design and if you need experimentally derived inputs
- throwaway4aday 3y ago
  Not if you're using new engines, new fuel systems, new heat shielding, new materials for the body, and making both the booster and second stage fully reusable by landing them with the help of a never before tried system that catches them before they touch the ground.
- stetrain 3y ago
  NASA has blown up a lot of RS-25s over decades in testing to get to that point. And a couple of Shuttles. When half your components have decades of reliability under their belt of course it’s easier to have a successful first launch. If your development methodology results in a product that is unsustainable to launch due to costs and scalability, that absolutely seems relevant to whether that methodology was successful.

brandonagr2 3y ago

While shamefully chucking RS-25s into the ocean

2OEH8eoCRo0 3y ago
And Starship blew up 39 raptor engines, and will probably blow up another 39 tomorrow.
- DarmokJalad1701 3y ago
  At least blowing up the raptor engines isn't the planned operational design. Even if they blow up 39 tomorrow, an operational Starship/Superheavy will not do that. That's the whole point. SLS is going to be tossing four RS-25 engines per launch (with *each* engine costing the same as ~2-3 entire Falcon 9 launches) into the ocean as the planned course of action. That is by design - and not some accident during a test flight.
- throwaway4aday 3y ago
  Rocketry advances one explosion at a time.
nordsieck 3y ago
People keep saying that. I don't really understand why. Sure, RS-25s were designed to be reusable. But it's not like they were being used for anything; they were just hanging out in a warehouse since the Shuttle days. If NASA was going to put them in a museum or something it would have already happened. At least this way, they get used for what they were designed for.