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> the most recent flight got the altitude for LEO, but not the velocity Starhship could easily have reached true orbit, they deliberately stopped just before i

> the most recent flight got the altitude for LEO, but not the velocity Starhship could easily have reached true orbit, they deliberately stopped just before it for safety reasons (don't want massive chunk of space junk if something goes wrong during deorbit)

pclmulqdq 3y ago
Is that their line? Musk companies have used that excuse a lot when they actually can't do something (see Tesla FSD). During the test flight, they called that orbital insertion was complete after they ran out of fuel (long before reaching orbital velocity), so I'm not buying it. Also, at that altitude, there's enough drag that you can de-orbit a big metal can pretty easily by simply pointing it in a high-drag orientation. Most LEO satellites do this when their missions are over, and it takes a couple weeks.
- simonh 3y ago
  They were venting excess fuel for some time after final trajectory insertion. There's no real question they could have achieved orbit handily.
- Georgelemental 3y ago
  Are we talking about the same test flight? They did not "run out of fuel" on IFT 3, maybe you are confusing with IFT 2 from last November?
  - pclmulqdq 3y ago
    Yes. "Starship engine cutoff" was called at 26,600 kph at 155 km altitude, when the fuel gauges for both LOX and CH4 on the stream were at 0. That altitude needs 28,000 kph for orbital velocity. A sister comment mentioned "venting excess fuel," which I don't believe was in the flight plan, but I would believe that the craft was leaking fuel given the clouds of gas around the thing on all the camera views (and the excess rotation in flight). That would explain how starship failed to make orbital velocity and still ran out of fuel. Presumably, if there was a leak and they fixed it, there wouldn't be any problems getting to orbit. But the fact of the matter is that they didn't reach orbit despite trying (getting into LEO was in the published plan), and the fuel gauges got to 0 before they got there. It's very possible that the valve between the tanks for the in-flight fuel transfer test (which didn't seem to happen successfully) was broken, so it's not actually a problem with starship at all, but a problem with the experimental setup.

pclmulqdq 3y ago

Is that their line? Musk companies have used that excuse a lot when they actually can't do something (see Tesla FSD). During the test flight, they called that orbital insertion was complete after they ran out of fuel (long before reaching orbital velocity), so I'm not buying it. Also, at that altitude, there's enough drag that you can de-orbit a big metal can pretty easily by simply pointing it in a high-drag orientation. Most LEO satellites do this when their missions are over, and it takes a couple weeks.

simonh 3y ago
They were venting excess fuel for some time after final trajectory insertion. There's no real question they could have achieved orbit handily.
Georgelemental 3y ago
Are we talking about the same test flight? They did not "run out of fuel" on IFT 3, maybe you are confusing with IFT 2 from last November?
- pclmulqdq 3y ago
  Yes. "Starship engine cutoff" was called at 26,600 kph at 155 km altitude, when the fuel gauges for both LOX and CH4 on the stream were at 0. That altitude needs 28,000 kph for orbital velocity. A sister comment mentioned "venting excess fuel," which I don't believe was in the flight plan, but I would believe that the craft was leaking fuel given the clouds of gas around the thing on all the camera views (and the excess rotation in flight). That would explain how starship failed to make orbital velocity and still ran out of fuel. Presumably, if there was a leak and they fixed it, there wouldn't be any problems getting to orbit. But the fact of the matter is that they didn't reach orbit despite trying (getting into LEO was in the published plan), and the fuel gauges got to 0 before they got there. It's very possible that the valve between the tanks for the in-flight fuel transfer test (which didn't seem to happen successfully) was broken, so it's not actually a problem with starship at all, but a problem with the experimental setup.