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> IFT3 got to orbital altitude, but not orbital velocity I don't think this is correct. "Starship reached orbital velocity!" - https://x.com/elonmusk/status/1

> IFT3 got to orbital altitude, but not orbital velocity I don't think this is correct. "Starship reached orbital velocity!" - https://x.com/elonmusk/status/1768271078999167379 https://x.com/elonmusk/status/1768271078999167379 "SpaceX's Starship mega rocket launched from Texas on its third test flight, reaching an altitude of 160 kilometers and achieving orbital velocity [...]" https://x.com/CBCNews/status/1768296197846884741 https://x.com/CBCNews/status/1768296197846884741

pclmulqdq 2y ago
If you look at the readings on the screen and do some basic physics instead of relying on the press releases of a biased party, you will realize that they were short of orbital velocity. At that altitude, orbital velocity is 27000 km/h, and IFT3 got to 21000-22000 km/h. As we're speaking, IFT4 has reached orbit.
- sbuttgereit 2y ago
  > IFT3 got to 21000-22000 km/h This is incorrect. It got to approximately the same velocity as this launch. > If you look at the readings on the screen Uhh.... OK.... https://youtu.be/W1WfCVZFZPo?si=XrVOUvsjxAHsvrLU&t=576 https://youtu.be/W1WfCVZFZPo?si=XrVOUvsjxAHsvrLU&t=576 > instead of relying on the press releases of a biased party Elon Musk... ok, he's a biased party. But I also quoted CBC News. Are you suggesting that they're biased or simply not terribly thorough?
  - pclmulqdq 2y ago
    CNBC parrots what SpaceX's press release says, and they have no other sources (see what they do with other corporations). And yes, they got closer than I thought, but still short for 170 km. 150 km has a higher orbital velocity. Edit: 28000 km/h at 150 km.
tekla 2y ago
They turned off the engines early specifically to not reach orbital velocity.
- pclmulqdq 2y ago
  There was an in-orbit relight in the IFT3 flight plan, which failed to happen. IFT4 is somewhat more conservative - just get to orbit (happened), pseudo-land the booster (happened), and get back out of orbit (remains to be seen). The amount of disinformation that SpaceX and Musk create around failed tests is really annoying and honestly somewhat problematic. It would be nice if SpaceX could just honestly say "this worked and this didn't," but we have to pretend that everything is a miraculous success. After the engine failed on IFT3, the immediate line was "we planned it this way" and then days later "we reached orbital velocity." Launching rockets is impressive enough that you don't have to try to gaslight us all on the way there. As far as I can tell, my scorecard has IFT1 and IFT3 as failures based on what the flight plans said going in, and IFT2 and (so far) IFT4 as successes. Edit: I'm suspicious of the fact that they turned off the feed right after cutting the engines and some gas vented. Previous tests have had no problem showing a video feed at this phase.
  - tekla 2y ago
    I'm always amazed at how wrong people on HN are. The orbital relight test was not a factor in the fact that Starship was not intended to reach orbital velocity. You may have noticed that the flight plan indicated that Starship was to land somewhere in the Indian ocean and usually reaching orbital velocity vastly increases the difficulty of doing a planned reentry. The flight plans had them turning off the engines before they actually reached orbital velocity They scrapped the relight test when they realized that they were losing control authority. The relight test was not meant for reaching orbit, it was to prove they COULD relight the engines on Starship while in space. Just stop being wrong.
    - pclmulqdq 2y ago
      The original IFT-3 flight plan had them reaching orbit and then doing the in-orbit relight as a de-orbit burn. At that altitude, there's enough drag that you will de-orbit pretty quickly if you are in orbit and your de-orbit burn fails, so there was no risk of a big piece of space junk. The disinformation I mentioned is why everyone keeps being "wrong" about SpaceX. It's incredibly difficult to be right. Here's the original graphic that SpaceX put out before the flight happened: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVxFzY9rdOu6cXly46axk8Wq2LH3tMqWEZOij9f3s2YjsWDPAycrsfQE1SgZ3f25OD7XOBIw_1WTRyKyZGUbLWHHLP9P0HSrGcB1kyEp8MGtWScjVbb_BkYOw_y_zNNZ2RvRYoljAL4693YPmQUOMPMzUoLYimNtqIkEAm6dBIoCGcnIRfNruobriImqoi/s2048/SpaceX%20Starship%20B10S28%20orbital%20flight%20test%203%20infographic%20by%20Tony%20Bela.jpg https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi...

pclmulqdq 2y ago

If you look at the readings on the screen and do some basic physics instead of relying on the press releases of a biased party, you will realize that they were short of orbital velocity. At that altitude, orbital velocity is 27000 km/h, and IFT3 got to 21000-22000 km/h. As we're speaking, IFT4 has reached orbit.

sbuttgereit 2y ago
> IFT3 got to 21000-22000 km/h This is incorrect. It got to approximately the same velocity as this launch. > If you look at the readings on the screen Uhh.... OK.... https://youtu.be/W1WfCVZFZPo?si=XrVOUvsjxAHsvrLU&t=576 https://youtu.be/W1WfCVZFZPo?si=XrVOUvsjxAHsvrLU&t=576 > instead of relying on the press releases of a biased party Elon Musk... ok, he's a biased party. But I also quoted CBC News. Are you suggesting that they're biased or simply not terribly thorough?
- pclmulqdq 2y ago
  CNBC parrots what SpaceX's press release says, and they have no other sources (see what they do with other corporations). And yes, they got closer than I thought, but still short for 170 km. 150 km has a higher orbital velocity. Edit: 28000 km/h at 150 km.

tekla 2y ago

They turned off the engines early specifically to not reach orbital velocity.

pclmulqdq 2y ago
There was an in-orbit relight in the IFT3 flight plan, which failed to happen. IFT4 is somewhat more conservative - just get to orbit (happened), pseudo-land the booster (happened), and get back out of orbit (remains to be seen). The amount of disinformation that SpaceX and Musk create around failed tests is really annoying and honestly somewhat problematic. It would be nice if SpaceX could just honestly say "this worked and this didn't," but we have to pretend that everything is a miraculous success. After the engine failed on IFT3, the immediate line was "we planned it this way" and then days later "we reached orbital velocity." Launching rockets is impressive enough that you don't have to try to gaslight us all on the way there. As far as I can tell, my scorecard has IFT1 and IFT3 as failures based on what the flight plans said going in, and IFT2 and (so far) IFT4 as successes. Edit: I'm suspicious of the fact that they turned off the feed right after cutting the engines and some gas vented. Previous tests have had no problem showing a video feed at this phase.
- tekla 2y ago
  I'm always amazed at how wrong people on HN are. The orbital relight test was not a factor in the fact that Starship was not intended to reach orbital velocity. You may have noticed that the flight plan indicated that Starship was to land somewhere in the Indian ocean and usually reaching orbital velocity vastly increases the difficulty of doing a planned reentry. The flight plans had them turning off the engines before they actually reached orbital velocity They scrapped the relight test when they realized that they were losing control authority. The relight test was not meant for reaching orbit, it was to prove they COULD relight the engines on Starship while in space. Just stop being wrong.
  - pclmulqdq 2y ago
    The original IFT-3 flight plan had them reaching orbit and then doing the in-orbit relight as a de-orbit burn. At that altitude, there's enough drag that you will de-orbit pretty quickly if you are in orbit and your de-orbit burn fails, so there was no risk of a big piece of space junk. The disinformation I mentioned is why everyone keeps being "wrong" about SpaceX. It's incredibly difficult to be right. Here's the original graphic that SpaceX put out before the flight happened: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiVxFzY9rdOu6cXly46axk8Wq2LH3tMqWEZOij9f3s2YjsWDPAycrsfQE1SgZ3f25OD7XOBIw_1WTRyKyZGUbLWHHLP9P0HSrGcB1kyEp8MGtWScjVbb_BkYOw_y_zNNZ2RvRYoljAL4693YPmQUOMPMzUoLYimNtqIkEAm6dBIoCGcnIRfNruobriImqoi/s2048/SpaceX%20Starship%20B10S28%20orbital%20flight%20test%203%20infographic%20by%20Tony%20Bela.jpg https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi...