5 ms·

I've been following SpaceX for years, and this is exactly my reaction today! Watching the belly flop and the (relatively) slow descent, it felt completely alien

by jvzr 6y ago

I've been following SpaceX for years, and this is exactly my reaction today! Watching the belly flop and the (relatively) slow descent, it felt completely alien, surreal. I'm in utter awe. Congrats to the teams involved, can't wait for SN9 and the rest of Starship!

fnord77 6y ago
the apollo lunar lander did pretty much the same thing.
- galacticaactual 6y ago
  The Apollo lunar lander objectively did not belly flop through atmosphere at 1G while having to deal with aerodynamic control surfaces.
- NikolaeVarius 6y ago
  Are you seriously comparing the Lunar Lander to this? The Lunar Lander was piloted since the computers couldn't do everything, but at the same time a human was good enough at piloting to be able to take over for what the computer couldn't do. This is the result of modern day CFD that that would take humans millions of years to do by hand
  - serf 6y ago
    >This is the result of modern day CFD that that would take humans millions of years to do by hand the package as a whole, yes. belly reorientation for flight has been a thing since the early American arms' race. It's a useful missile trait. Gimbaled vector rockets have existed since the 1940s.[0] Yes, restart is very important -- it's not a requirement for atmospheric belly flight, though. [0]: https://en.wikipedia.org/wiki/RTV-A-2_Hiroc https://en.wikipedia.org/wiki/RTV-A-2_Hiroc
    - HPsquared 6y ago
      Nailing the transition to and from belly flight is the hard part, especially so when it's so close to the ground with little margin for error.
      - ddalex 6y ago
        Military have been doing the belly flop for years https://www.youtube.com/watch?v=o9vljzfywJI https://www.youtube.com/watch?v=o9vljzfywJI
    - Gravityloss 6y ago
      Alpha Draco was testing body lift in the fifties https://en.wikipedia.org/wiki/Alpha_Draco https://en.wikipedia.org/wiki/Alpha_Draco Robert Brulle has a fascinating memoir https://www.airuniversity.af.edu/Portals/10/AUPress/Books/B_0113_BRULLE_ENGINEERING_SPACE_AGE.pdf https://www.airuniversity.af.edu/Portals/10/AUPress/Books/B_...
  - davegauer 6y ago
    Aside: the book Digital Apollo[0] gave me the impression that the computer might well have been able to land, but we'll never know since the astronauts didn't trust it enough to find out. [0] https://mitpress.mit.edu/books/digital-apollo https://mitpress.mit.edu/books/digital-apollo

by jvzr 6y ago

fnord77 6y ago

the apollo lunar lander did pretty much the same thing.

galacticaactual 6y ago
The Apollo lunar lander objectively did not belly flop through atmosphere at 1G while having to deal with aerodynamic control surfaces.
NikolaeVarius 6y ago
Are you seriously comparing the Lunar Lander to this? The Lunar Lander was piloted since the computers couldn't do everything, but at the same time a human was good enough at piloting to be able to take over for what the computer couldn't do. This is the result of modern day CFD that that would take humans millions of years to do by hand
- serf 6y ago
  >This is the result of modern day CFD that that would take humans millions of years to do by hand the package as a whole, yes. belly reorientation for flight has been a thing since the early American arms' race. It's a useful missile trait. Gimbaled vector rockets have existed since the 1940s.[0] Yes, restart is very important -- it's not a requirement for atmospheric belly flight, though. [0]: https://en.wikipedia.org/wiki/RTV-A-2_Hiroc https://en.wikipedia.org/wiki/RTV-A-2_Hiroc
  - HPsquared 6y ago
    Nailing the transition to and from belly flight is the hard part, especially so when it's so close to the ground with little margin for error.
    - ddalex 6y ago
      Military have been doing the belly flop for years https://www.youtube.com/watch?v=o9vljzfywJI https://www.youtube.com/watch?v=o9vljzfywJI
  - Gravityloss 6y ago
    Alpha Draco was testing body lift in the fifties https://en.wikipedia.org/wiki/Alpha_Draco https://en.wikipedia.org/wiki/Alpha_Draco Robert Brulle has a fascinating memoir https://www.airuniversity.af.edu/Portals/10/AUPress/Books/B_0113_BRULLE_ENGINEERING_SPACE_AGE.pdf https://www.airuniversity.af.edu/Portals/10/AUPress/Books/B_...
- davegauer 6y ago
  Aside: the book Digital Apollo[0] gave me the impression that the computer might well have been able to land, but we'll never know since the astronauts didn't trust it enough to find out. [0] https://mitpress.mit.edu/books/digital-apollo https://mitpress.mit.edu/books/digital-apollo