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The videos are great!, but the rest of it is never going to work lol, just never. Even without a rethink about how to get heavy payloads to another planet this

The videos are great!, but the rest of it is never going to work lol, just never. Even without a rethink about how to get heavy payloads to another planet this is still good entertainment.

itsthecourier 4mo ago
why won't it ever work?
- globalnode 4mo ago
  Even if it landed perfectly how is it going to be rapidly reusable with all those tiles breaking and needing repair? Then if that problem was magically engineered-away through some sort of materials science breakthrough, it still makes more sense to me to keep your big ships in a space staging area and your smaller ones as atmospheric gophers.
  - s1artibartfast 4mo ago
    Small ships are less efficient, especially leaving the gravity well. Thats the whole point
    - JPLeRouzic 4mo ago
      Could you tell me more? I suppose a heavy two-stage rocket is not optimized from the point of view of the rocket equation, but I know nothing about this field.
      - s1artibartfast 4mo ago
        In short, the more stages the better to discard mass once it isnt necessary, and the larger to the better to improve the ratio of (ship+payload) to fuel. Here is a decent summary. https://gemini.google.com/share/121466b300c1 https://gemini.google.com/share/121466b300c1
        kibwen 4mo ago
        This is only true to an extent. Yes, a larger rocket means a better mass:payload ratio, but a larger rocket also means more mass in absolute terms, and more mass means more fuel, and more fuel means more mass, and more mass means more fuel, and more fuel means more mass, and so on. This is "the tyranny of the rocket equation", and it places an upper bound on the size of rockets that need to carry their own fuel for a given gravity well. And because the larger absolute mass of a larger rocket means more fuel, which means more cost, it relies on actually being able to find enough paying customers to fill out that payload capacity every single time. This is why, for example, despite the existence of jumbo jets (which have a better mass:payload ration than smaller planes), most passenger flights are not on jumbo jets, because there's just not enough demand on most routes.
        murderfs 4mo ago
        > This is why, for example, despite the existence of jumbo jets (which have a better mass:payload ration than smaller planes), most passenger flights are not on jumbo jets, because there's just not enough demand on most routes. Airlines used to use a hub and spoke model where it would make sense to have larger planes between hubs and smaller ones to get to and from the hubs, but consumers strongly preferred direct routing, so it didn't work out. For orbital payloads, most payloads probably do not mind too much if it takes a month or more to boost/deboost themselves to their intended orbits.
        NetMageSCW 4mo ago
        No it doesn’t matter if the payload is full or not. If they succeed in full reuse, flying on a mostly empty Starship will be ten times cheaper than flying on an F9 and that means everything will switch eventually. If a jumbo jet was ten times more efficient than a smaller plane, they would go everywhere. If a giant pickup truck got a 100MPG, why would you take a 30MPG economy sedan anywhere?
        s1artibartfast 4mo ago
        You fundamentally misunderstand the implications of the rocket equation. It does not put and upper limit on rocket size for a given gravity. Smaller rockets would not be successful where larger fail. Due to strucrually efficiency, larger ones suceede where smaller fail due to higher m0/mf ratio
  - laughing_man 4mo ago
    All what tiles breaking and needing repair? There was remarkably little visible damage this time around compared with previous flights. There's no materials science breakthrough needed -- the shuttle used ceramic tiles successfully its entire service life. What's needed is engineering work, and that's what SpaceX has been doing.
    - fooblaster 4mo ago
      You know a whole the size of a quarter can wreck the entire spacecraft and make it effectively throw away? Also, you'd want to use this many times. Making a system robust while not requiring months of refurbishment is really really hard.
      - ceejayoz 4mo ago
        The Space Shuttle had that problem because it was aluminum with a much lower melting point. It’s one of the reasons they’re using steel. We’ve seen much larger holes than that in previous tests. Some of the control fins burned completely through.
      - GuB-42 4mo ago
        For some of the tests, they removed a few tiles before launch, presumably to test that. Starship did fine.
        fooblaster 4mo ago
        coming back in one piece, and being good enough to use for 5 more missions are two very different things. For example, all existing reentry vehicles come back "fine" but they need to be completely remade to go up again.
        ceejayoz 4mo ago
        I remember this being the same argument used against the Falcon 9 when it first stuck its landings. "Oh, they'll need to do it 10x to be profitable!" Now they do, as a matter of course.
  - NetMageSCW 4mo ago
    They’ve already demonstrated they can replace all the tiles in a couple of days - even if they continue to have some fall off it won’t be an issue.
- fooblaster 4mo ago
  The hardest problem in the entire design had yet to be solved. Having a robust human rated tile system that can be rapidly turned around is a huge engineering challenge that kind of breaks the whole point of the design if it doesn't work. I wouldn't be surprised if they eventually give up and go back to a cheaper throw away second stage, or throw out the tile design completely and try for some evaporative cooling approach, again.
  - oconnor663 4mo ago
    Bear in mind that a lot of what's happening to the tiles now is deliberate experiments to see how much weight they can shave off and how many failed tiles they can survive. Given that the vehicle is routinely surviving reentry at this point, it doesn't seem "hard" to make the tiles more robust by paying for it with added weight. The question is whether they'll have enough weight budget to pay for it? But at this point...probably? Not my area ofc.
    - fooblaster 4mo ago
      "surviving reentry" and being reusable are two very different things, particularly if this is to become human rated.
      - NetMageSCW 4mo ago
        Human rating is irrelevant to what they want to do, it is only a NASA rating - if NASA wants to ride they will have to come up with a rationale but private astronauts can fly on it.
        globalnode 4mo ago
        From day one they said their vision was to replace airlines for international air travel.
        Zigurd 4mo ago
- MrSkelter 4mo ago
  The design is wrong in a fundamental level. The rocket equation says it all. By adding so much extra weight for “reusability” (which they don’t release numbers on in terms of cost and means nothing when the rockets end up in the Indian Ocean) they nerf the performance. Hence tens of launches to make the moon and zero payload to orbit in a dozen flights. This forum is full of fanboys but their arguments don’t hold up to reality. Saturn 5 had men on the mock. This much time and this many rockets in. Starship has launched a dozen times for $15B - over a billion per launch - and it hasn’t made orbit. Say what you want about SLS, it works. Musk is a conman and Starship is a failure. Like the F-35 supposed libertarians and conservatives will happily throw money at it until it achieves its targets, after multiple redesigns, and then claim success as if the neigh-sayers weren’t right all along.
globalnode 4mo ago
While we're downing this I'd like to add I think the "I've written X in Rust" posts are also cringe :D

The videos are great!, but the rest of it is never going to work lol, just never. Even without a rethink about how to get heavy payloads to another planet this is still good entertainment.

itsthecourier 4mo ago

why won't it ever work?

globalnode 4mo ago
Even if it landed perfectly how is it going to be rapidly reusable with all those tiles breaking and needing repair? Then if that problem was magically engineered-away through some sort of materials science breakthrough, it still makes more sense to me to keep your big ships in a space staging area and your smaller ones as atmospheric gophers.
- s1artibartfast 4mo ago
  Small ships are less efficient, especially leaving the gravity well. Thats the whole point
  - JPLeRouzic 4mo ago
    Could you tell me more? I suppose a heavy two-stage rocket is not optimized from the point of view of the rocket equation, but I know nothing about this field.
    - s1artibartfast 4mo ago
      In short, the more stages the better to discard mass once it isnt necessary, and the larger to the better to improve the ratio of (ship+payload) to fuel. Here is a decent summary. https://gemini.google.com/share/121466b300c1 https://gemini.google.com/share/121466b300c1
      - kibwen 4mo ago
        This is only true to an extent. Yes, a larger rocket means a better mass:payload ratio, but a larger rocket also means more mass in absolute terms, and more mass means more fuel, and more fuel means more mass, and more mass means more fuel, and more fuel means more mass, and so on. This is "the tyranny of the rocket equation", and it places an upper bound on the size of rockets that need to carry their own fuel for a given gravity well. And because the larger absolute mass of a larger rocket means more fuel, which means more cost, it relies on actually being able to find enough paying customers to fill out that payload capacity every single time. This is why, for example, despite the existence of jumbo jets (which have a better mass:payload ration than smaller planes), most passenger flights are not on jumbo jets, because there's just not enough demand on most routes.
        murderfs 4mo ago
        > This is why, for example, despite the existence of jumbo jets (which have a better mass:payload ration than smaller planes), most passenger flights are not on jumbo jets, because there's just not enough demand on most routes. Airlines used to use a hub and spoke model where it would make sense to have larger planes between hubs and smaller ones to get to and from the hubs, but consumers strongly preferred direct routing, so it didn't work out. For orbital payloads, most payloads probably do not mind too much if it takes a month or more to boost/deboost themselves to their intended orbits.
        NetMageSCW 4mo ago
        No it doesn’t matter if the payload is full or not. If they succeed in full reuse, flying on a mostly empty Starship will be ten times cheaper than flying on an F9 and that means everything will switch eventually. If a jumbo jet was ten times more efficient than a smaller plane, they would go everywhere. If a giant pickup truck got a 100MPG, why would you take a 30MPG economy sedan anywhere?
        s1artibartfast 4mo ago
        You fundamentally misunderstand the implications of the rocket equation. It does not put and upper limit on rocket size for a given gravity. Smaller rockets would not be successful where larger fail. Due to strucrually efficiency, larger ones suceede where smaller fail due to higher m0/mf ratio
- laughing_man 4mo ago
  All what tiles breaking and needing repair? There was remarkably little visible damage this time around compared with previous flights. There's no materials science breakthrough needed -- the shuttle used ceramic tiles successfully its entire service life. What's needed is engineering work, and that's what SpaceX has been doing.
  - fooblaster 4mo ago
    You know a whole the size of a quarter can wreck the entire spacecraft and make it effectively throw away? Also, you'd want to use this many times. Making a system robust while not requiring months of refurbishment is really really hard.
    - ceejayoz 4mo ago
      The Space Shuttle had that problem because it was aluminum with a much lower melting point. It’s one of the reasons they’re using steel. We’ve seen much larger holes than that in previous tests. Some of the control fins burned completely through.
    - GuB-42 4mo ago
      For some of the tests, they removed a few tiles before launch, presumably to test that. Starship did fine.
      - fooblaster 4mo ago
        coming back in one piece, and being good enough to use for 5 more missions are two very different things. For example, all existing reentry vehicles come back "fine" but they need to be completely remade to go up again.
        ceejayoz 4mo ago
        I remember this being the same argument used against the Falcon 9 when it first stuck its landings. "Oh, they'll need to do it 10x to be profitable!" Now they do, as a matter of course.
- NetMageSCW 4mo ago
  They’ve already demonstrated they can replace all the tiles in a couple of days - even if they continue to have some fall off it won’t be an issue.
fooblaster 4mo ago
The hardest problem in the entire design had yet to be solved. Having a robust human rated tile system that can be rapidly turned around is a huge engineering challenge that kind of breaks the whole point of the design if it doesn't work. I wouldn't be surprised if they eventually give up and go back to a cheaper throw away second stage, or throw out the tile design completely and try for some evaporative cooling approach, again.
- oconnor663 4mo ago
  Bear in mind that a lot of what's happening to the tiles now is deliberate experiments to see how much weight they can shave off and how many failed tiles they can survive. Given that the vehicle is routinely surviving reentry at this point, it doesn't seem "hard" to make the tiles more robust by paying for it with added weight. The question is whether they'll have enough weight budget to pay for it? But at this point...probably? Not my area ofc.
  - fooblaster 4mo ago
    "surviving reentry" and being reusable are two very different things, particularly if this is to become human rated.
    - NetMageSCW 4mo ago
      Human rating is irrelevant to what they want to do, it is only a NASA rating - if NASA wants to ride they will have to come up with a rationale but private astronauts can fly on it.
      - globalnode 4mo ago
        From day one they said their vision was to replace airlines for international air travel.
        Zigurd 4mo ago
MrSkelter 4mo ago
The design is wrong in a fundamental level. The rocket equation says it all. By adding so much extra weight for “reusability” (which they don’t release numbers on in terms of cost and means nothing when the rockets end up in the Indian Ocean) they nerf the performance. Hence tens of launches to make the moon and zero payload to orbit in a dozen flights. This forum is full of fanboys but their arguments don’t hold up to reality. Saturn 5 had men on the mock. This much time and this many rockets in. Starship has launched a dozen times for $15B - over a billion per launch - and it hasn’t made orbit. Say what you want about SLS, it works. Musk is a conman and Starship is a failure. Like the F-35 supposed libertarians and conservatives will happily throw money at it until it achieves its targets, after multiple redesigns, and then claim success as if the neigh-sayers weren’t right all along.

globalnode 4mo ago

While we're downing this I'd like to add I think the "I've written X in Rust" posts are also cringe :D