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Tangential thought: It really seems to me that only companies with the "California tech startup mentality" (whether they're in Cali or not) can actually do any

by api 13y ago

Tangential thought: It really seems to me that only companies with the "California tech startup mentality" (whether they're in Cali or not) can actually do anything today. I'm starting to refer to the rest of the economy as the "legacy economy," "legacy industry," etc. I understand some of the reasons: bottom-up engineer-led engineering teams, lean operations, little or no bureaucracy compared to large older institutions, etc. But there seems to be something else too, some kind of difficult to quantify attitude or mentality. I get it, but I find it hard to describe except to say it's about believing in the future, believing that things are actually possible. Everyone else everywhere else seems to be looking backward and thinking of all the reasons things can't be done. Like this, for example. "Here, we're NASA, and here's why it can't be done." The NASA of the 50s and the 60s is rolling in its grave! Legacy economy indeed. Disrupt everything. Ditch it all and start over.

InclinedPlane 13y ago
Indeed. There are folks who see disruption as valuable and those who see it is as risky, dangerous. As to the NASA of the 1960s, that was a NASA who developed 4 different manned spacecraft in a 10 year period (Mercury, Gemini, Apollo CM & Apollo LM) and flew them on 4 different rockets (Atlas, Titan, Saturn I, Saturn V). That's the sort of activity that looks similar to what SpaceX is doing today and very dissimilar to what NASA is doing today (sinking billions per year into masses of bureaucratic BS and very little hardware).
- hga 13y ago
  Five different rockets! The first suborbital Mercury flights used Redstones, V-2 descendants that used alcohol and LOX. Followed by the Atlas that used kerosene and LOX like Space X, the Titan which used fuels that could be stored in the rocket for long terms, making it a practical ICBM (taken out of service in the mid-80s). All those were adopted from military missiles, and were followed by the purpose built Saturn I and V, and both of their first stages also used kerosene and LOX. Am I seeing a pattern here ^_^? (Quibbles: the "kerosene" used in rockets is actually highly refined stuff: https://en.wikipedia.org/wiki/RP-1 https://en.wikipedia.org/wiki/RP-1 and the Saturn upper stages used liquid hydrogen and LOX.)
  - InclinedPlane 13y ago
    Hydrogen was used for the Saturn upper stages for performance reasons, since at the time that was more important than cost. If cost is a concern it's generally cheaper just to build a larger rocket and use LOX/Kerosene everywhere. The fascinating thing about rocket development throughout history is that almost none of it has ever been truly cost sensitive. The big advantage for SpaceX in using the same propellant and mostly the same engine in the 2nd stage on the Falcon 9 is that the 2nd stage is dirt cheap. In any other rocket they'd see the opportunity to build a small little LOX/LH2 stage and improve the payload tremendously. But then you'd end up with a lot of cost in the 2nd stage, which is precisely what SpaceX doesn't want. With the Falcon 9 design 3/4 of the manufacturing cost is in the first stage. Which means that reusing just the first stage (by far the easiest reusability prospect) nets huge gains. This is what you call low lying fruit. And it's fruit that would have been there for anyone else to pick except they kept making the tree taller without thinking about it, instead of just picking the fruit. So now instead of a more expensive rocket with more payload SpaceX ends up with a vastly less expensive rocket with slightly less payload (easily worked around with the Falcon Heavy configuration). Even just 2 reflights of the first stage translates to an overall reduction of 50% in the capital cost of each flight (or 60% in the case of the FH).
    - hga 13y ago
      "easily worked around with the Falcon Heavy configuration" I'm a little concerned about the propellant crossfeed aspect of the Falcon Heavy (the liquid boosters on the sides feed propellant to the core, which will be mostly full when they separate ... and that's much sooner than a normal Falcon 9 first stage is finished boosting, might make reusability easier). If they pull it off they'll be the first ever, right? Not saying they can't, but unlike almost everything else they're doing, this is new "rocket science" to my limited knowledge.
      - InclinedPlane 13y ago
        It's not crazy complicated. And the Shuttle was fed by an external tank as well. The way it will work with the Falcon Heavy (when that much payload capacity is desired) is that the 3 engines on each side in the center booster will each feed from the nearest outer cores during liftoff. When those cores are empty the feed will be stopped, those 6 engines will shut down, the outer cores will separate, and then the 6 engines will come online again fueled by the center core. It's mostly just valve work, to be honest. Also, even if it doesn't work it's not a huge deal long term. It means that we'll be deprived of the highest payload capacities for an expendable Falcon Heavy but we'll still have a fairly high (20+ tonne to LEO) capacity booster in a reusable configuration, which will probably be more impactful in the long run than the expendable configuration.

by api 13y ago

InclinedPlane 13y ago

Indeed. There are folks who see disruption as valuable and those who see it is as risky, dangerous. As to the NASA of the 1960s, that was a NASA who developed 4 different manned spacecraft in a 10 year period (Mercury, Gemini, Apollo CM & Apollo LM) and flew them on 4 different rockets (Atlas, Titan, Saturn I, Saturn V). That's the sort of activity that looks similar to what SpaceX is doing today and very dissimilar to what NASA is doing today (sinking billions per year into masses of bureaucratic BS and very little hardware).

hga 13y ago
Five different rockets! The first suborbital Mercury flights used Redstones, V-2 descendants that used alcohol and LOX. Followed by the Atlas that used kerosene and LOX like Space X, the Titan which used fuels that could be stored in the rocket for long terms, making it a practical ICBM (taken out of service in the mid-80s). All those were adopted from military missiles, and were followed by the purpose built Saturn I and V, and both of their first stages also used kerosene and LOX. Am I seeing a pattern here ^_^? (Quibbles: the "kerosene" used in rockets is actually highly refined stuff: https://en.wikipedia.org/wiki/RP-1 https://en.wikipedia.org/wiki/RP-1 and the Saturn upper stages used liquid hydrogen and LOX.)
- InclinedPlane 13y ago
  Hydrogen was used for the Saturn upper stages for performance reasons, since at the time that was more important than cost. If cost is a concern it's generally cheaper just to build a larger rocket and use LOX/Kerosene everywhere. The fascinating thing about rocket development throughout history is that almost none of it has ever been truly cost sensitive. The big advantage for SpaceX in using the same propellant and mostly the same engine in the 2nd stage on the Falcon 9 is that the 2nd stage is dirt cheap. In any other rocket they'd see the opportunity to build a small little LOX/LH2 stage and improve the payload tremendously. But then you'd end up with a lot of cost in the 2nd stage, which is precisely what SpaceX doesn't want. With the Falcon 9 design 3/4 of the manufacturing cost is in the first stage. Which means that reusing just the first stage (by far the easiest reusability prospect) nets huge gains. This is what you call low lying fruit. And it's fruit that would have been there for anyone else to pick except they kept making the tree taller without thinking about it, instead of just picking the fruit. So now instead of a more expensive rocket with more payload SpaceX ends up with a vastly less expensive rocket with slightly less payload (easily worked around with the Falcon Heavy configuration). Even just 2 reflights of the first stage translates to an overall reduction of 50% in the capital cost of each flight (or 60% in the case of the FH).
  - hga 13y ago
    "easily worked around with the Falcon Heavy configuration" I'm a little concerned about the propellant crossfeed aspect of the Falcon Heavy (the liquid boosters on the sides feed propellant to the core, which will be mostly full when they separate ... and that's much sooner than a normal Falcon 9 first stage is finished boosting, might make reusability easier). If they pull it off they'll be the first ever, right? Not saying they can't, but unlike almost everything else they're doing, this is new "rocket science" to my limited knowledge.
    - InclinedPlane 13y ago
      It's not crazy complicated. And the Shuttle was fed by an external tank as well. The way it will work with the Falcon Heavy (when that much payload capacity is desired) is that the 3 engines on each side in the center booster will each feed from the nearest outer cores during liftoff. When those cores are empty the feed will be stopped, those 6 engines will shut down, the outer cores will separate, and then the 6 engines will come online again fueled by the center core. It's mostly just valve work, to be honest. Also, even if it doesn't work it's not a huge deal long term. It means that we'll be deprived of the highest payload capacities for an expendable Falcon Heavy but we'll still have a fairly high (20+ tonne to LEO) capacity booster in a reusable configuration, which will probably be more impactful in the long run than the expendable configuration.