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Starship's Third Flight Test [video]

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Re: Starship's Third Flight Test [video]

#131

Earlier quoted context omitted.

I think they also successfully demoed in-space fuel transfer.

Fuel transfer with what? That would require things like docking

Transfer internally between tanks in the bottom and top of the ship. This was one of the planned tests, I have not heard whether it was accomplished though.

Re: Starship's Third Flight Test [video]

#132
post #123

The test is essentially a success at this point. Starship can take payload to orbit and open/close the payload doors. The remaining things are icing on the cake. They can refine re-usability while flying payloads.

Not quite: the apogee burn they had planned didn't happen (no word as to why yet), so the ship didn't technically demonstrate the capability reach orbit. It came back down in the Indian ocean on its original suborbital trajectory, essentially like an ICBM.

That is a matter of the trajectory they chose on purpose for this test flight. A different flight profile would have given them a perigee above the atmosphere (rather than -50 km)

Re: Starship's Third Flight Test [video]

#133
post #112

Looked very impressive and there is enormous progress compared to the earlier tests. Especially as all engines seemed to work throughout the entire launch, the earlier tests had significant engine troubles so they seem to have a handle on that now. The reentry burn failing doesn't seem like a huge deal in this case, especially as the engines worked very well earlier.

Its still an issue because they haven't really confidently demonstrated a relight of the engines while flying. Hot staging avoids a relight, but they still need to do it. It does mean they technically have an expendable heavy launch vehicle though.

The boostback burn demonstrated relight today.

Re: Starship's Third Flight Test [video]

#134

Earlier quoted context omitted.

I think they also successfully demoed in-space fuel transfer.

Fuel transfer with what? That would require things like docking

They performed an in-ship fuel transfer, from one chamber to another. My understanding is that this is a very important pre-requisite for an actual transfer from one ship to another, because of the need to keep the fuel at cryogenic temperatures during the transfer, which is apparently not easy. Last time it was done was decades ago, but in kilograms. SpaceX just demoed a transfer of tons of fuel.

Re: Starship's Third Flight Test [video]

#135
post #102

Earlier quoted context omitted.

Orbit is a speed, not a distance. You could do a suborbital hop that has its highest point beyond the orbit of the moon. (if you aim very, very well)

At the same time, if your velocity vector is pointing towards the ground you're not achieving orbit no matter your speed

It works if you're a black hole or a chunk of degenerate matter. For transatmospheric orbits being a large ball of iridium will work too.

Re: Starship's Third Flight Test [video]

#137

those plasma views when starship was coming into atmosphere were absolutely mind blowing. it makes a lot of sense to use starlink for this, but it never ever crossed my mind.

video: https://twitter.com/SpaceX/status/1768279990368612354

Note the camera moves because its also on a flap

Re: Starship's Third Flight Test [video]

#138

The test is essentially a success at this point. Starship can take payload to orbit and open/close the payload doors. The remaining things are icing on the cake. They can refine re-usability while flying payloads.

I wouldn’t classify the re-entry survival problem as icing. But otherwise, I agree with you.

Yeah, breaking up in-air during re-entry (at 65 km going by last telemetry) seems like a potential big issue to fix.

Re: Starship's Third Flight Test [video]

#140
post #112

Looked very impressive and there is enormous progress compared to the earlier tests. Especially as all engines seemed to work throughout the entire launch, the earlier tests had significant engine troubles so they seem to have a handle on that now. The reentry burn failing doesn't seem like a huge deal in this case, especially as the engines worked very well earlier.

Its still an issue because they haven't really confidently demonstrated a relight of the engines while flying. Hot staging avoids a relight, but they still need to do it. It does mean they technically have an expendable heavy launch vehicle though.

> It does mean they technically have an expendable heavy launch vehicle though.

That is how they started using Falcon 9 as well: first expendable but testing recovery - which failed several times in several interesting ways - until that process was refined into what now seems to be a normal thing: the first stage launches, drops off a second stage, turns around and makes its way back to either the launch site or a floating platform. I assume they have the same plans for this system: launch expendable while using the hardware to refine the process of recovery until in not that many years from now they launch and land and launch again.

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