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Participation in the second NSSL requires vertical payload integration. SpaceX had to promise to be able to do it to submit a bid. They have never done it so f

Participation in the second NSSL requires vertical payload integration. SpaceX had to promise to be able to do it to submit a bid. They have never done it so far, but they will definitely do it in the near future.

tomatoman 6y ago
What is vertical payload integration?
- JshWright 6y ago
  With rockets like the Atlas 5 (flown by ULA), the rocket is assembled vertically in a tall "hanger", and is then rolled out to the launch pad, remaining in the vertical position. The Falcon 9 is assembled rolled out to the pad horizontally, then it raised into the vertical position in preparation for launch. It can be more complicated to design satellites (esp satellites that have large optics in them) to deal with gravity in two different orientations. Atlas 5 "roll out": https://spaceflightnow.com/2020/07/28/photos-atlas-5-rolled-out-to-launch-pad-with-nasas-perseverance-mars-rover/ https://spaceflightnow.com/2020/07/28/photos-atlas-5-rolled-... Falcon 9: https://www.youtube.com/watch?v=TYJuHuhPxGU https://www.youtube.com/watch?v=TYJuHuhPxGU Bonus video, Smarter Every Day chatting w/ the CEO of ULA while watching a Delta IV Heavy roll out to the launch pad: https://www.youtube.com/watch?v=OdPoVi_h0r0 https://www.youtube.com/watch?v=OdPoVi_h0r0
  - sandworm101 6y ago
    Complicated and less weight-efficient. Designing a structure for gravity/g/force in one axis is wasteful enough. That strength is useless once in space. Horizontal integration means the structure must be strong in two axis: double waste. It might not matter when you are launching cubesats, but in a spy satellite the size/weight of a bus that extra reinforcement means sacrifices in many other areas.
    - avmich 6y ago
      But it's more economical, money-wise, as Russian launchers history shows. In general, American rocket school tends to have better mass efficiency but less economical efficiency that Russian rocket school. "When he wants more thrust, Ivan doesn't look for a fancy propellant with a higher specific impulse. He just builds himself a bigger rocket. Maybe he's got something there." - J. Clark, Ignition! https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...
      - dnautics 6y ago
        > When he wants more thrust, Ivan doesn't look for a fancy propellant with a higher specific impulse. He just builds himself a bigger rocket On the other hand the Soviet Union did develop syntin... (also from Ignition!)
        avmich 6y ago
        Of course the point was that one can use simple and crude solutions, or effective and sophisticated ones. Another example would be that in Russian rocket engines pumps tend to be put on the same axis as the turbine, so frequencies of turbine and pumps are the same and some of them can be non-optimal. In American tradition one uses gears, which makes both turbine and pumps (more) optimal, for the cost of gear mechanism. Practice shows that both approaches can work, but, just as with vertical assembly, which requires a tall building or a vertical transportation of a rocket, some ways look simpler than others. Simpler not necessarily better - but in rocket assembly it's probably cheaper to do it horizontally.
    - jccooper 6y ago
      It's a bit more than cubesats. Nearly every satellite is or can be fine with horizontal integration. Witness every SpaceX and Russian payload ever launched. Only exotic (presumably optical) sats from three-letter agencies really demand it, and even then we don't know if they really need it or would rather just spend the money to make it the launcher's problem rather than do a redesign or evaluation of their system.
  - garmaine 6y ago
    How is the satellite transported to the launch site from the point of manufacture?
    - JshWright 6y ago
      Usually by truck for at least part of the journey (airplanes, boats, and trains are also commonly used). They are carried in custom built frames that hold them in the correct orientation. The frame is then surrounded by a sealed box that keeps the satellite clean, and with the appropriate climate controls (temperature, humidity, etc). Here's a good overview of the process (though in this case it's a satellite that can safely be transported in multiple orientations): https://qz.com/1346279/big-plane/ https://qz.com/1346279/big-plane/
      - garmaine 6y ago
        It just seems to me that it would need to be horizontal, and likely encounter greater stresses during transport than during a tightly controlled horizontal assembly process.
        Tuna-Fish 6y ago
        They are not horizontal during transport.
- wwwwwwwww 6y ago
  ULA basically built a portable clean room around the tip of the vertical rocket, to put the payload on top. Because the rover has to be free of earth organisms.

tomatoman 6y ago

What is vertical payload integration?

JshWright 6y ago
With rockets like the Atlas 5 (flown by ULA), the rocket is assembled vertically in a tall "hanger", and is then rolled out to the launch pad, remaining in the vertical position. The Falcon 9 is assembled rolled out to the pad horizontally, then it raised into the vertical position in preparation for launch. It can be more complicated to design satellites (esp satellites that have large optics in them) to deal with gravity in two different orientations. Atlas 5 "roll out": https://spaceflightnow.com/2020/07/28/photos-atlas-5-rolled-out-to-launch-pad-with-nasas-perseverance-mars-rover/ https://spaceflightnow.com/2020/07/28/photos-atlas-5-rolled-... Falcon 9: https://www.youtube.com/watch?v=TYJuHuhPxGU https://www.youtube.com/watch?v=TYJuHuhPxGU Bonus video, Smarter Every Day chatting w/ the CEO of ULA while watching a Delta IV Heavy roll out to the launch pad: https://www.youtube.com/watch?v=OdPoVi_h0r0 https://www.youtube.com/watch?v=OdPoVi_h0r0
- sandworm101 6y ago
  Complicated and less weight-efficient. Designing a structure for gravity/g/force in one axis is wasteful enough. That strength is useless once in space. Horizontal integration means the structure must be strong in two axis: double waste. It might not matter when you are launching cubesats, but in a spy satellite the size/weight of a bus that extra reinforcement means sacrifices in many other areas.
  - avmich 6y ago
    But it's more economical, money-wise, as Russian launchers history shows. In general, American rocket school tends to have better mass efficiency but less economical efficiency that Russian rocket school. "When he wants more thrust, Ivan doesn't look for a fancy propellant with a higher specific impulse. He just builds himself a bigger rocket. Maybe he's got something there." - J. Clark, Ignition! https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...
    - dnautics 6y ago
      > When he wants more thrust, Ivan doesn't look for a fancy propellant with a higher specific impulse. He just builds himself a bigger rocket On the other hand the Soviet Union did develop syntin... (also from Ignition!)
      - avmich 6y ago
        Of course the point was that one can use simple and crude solutions, or effective and sophisticated ones. Another example would be that in Russian rocket engines pumps tend to be put on the same axis as the turbine, so frequencies of turbine and pumps are the same and some of them can be non-optimal. In American tradition one uses gears, which makes both turbine and pumps (more) optimal, for the cost of gear mechanism. Practice shows that both approaches can work, but, just as with vertical assembly, which requires a tall building or a vertical transportation of a rocket, some ways look simpler than others. Simpler not necessarily better - but in rocket assembly it's probably cheaper to do it horizontally.
  - jccooper 6y ago
    It's a bit more than cubesats. Nearly every satellite is or can be fine with horizontal integration. Witness every SpaceX and Russian payload ever launched. Only exotic (presumably optical) sats from three-letter agencies really demand it, and even then we don't know if they really need it or would rather just spend the money to make it the launcher's problem rather than do a redesign or evaluation of their system.
- garmaine 6y ago
  How is the satellite transported to the launch site from the point of manufacture?
  - JshWright 6y ago
    Usually by truck for at least part of the journey (airplanes, boats, and trains are also commonly used). They are carried in custom built frames that hold them in the correct orientation. The frame is then surrounded by a sealed box that keeps the satellite clean, and with the appropriate climate controls (temperature, humidity, etc). Here's a good overview of the process (though in this case it's a satellite that can safely be transported in multiple orientations): https://qz.com/1346279/big-plane/ https://qz.com/1346279/big-plane/
    - garmaine 6y ago
      It just seems to me that it would need to be horizontal, and likely encounter greater stresses during transport than during a tightly controlled horizontal assembly process.
      - Tuna-Fish 6y ago
        They are not horizontal during transport.
wwwwwwwww 6y ago
ULA basically built a portable clean room around the tip of the vertical rocket, to put the payload on top. Because the rover has to be free of earth organisms.