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Starship's Fourth Flight Test [video]

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Re: Starship's Fourth Flight Test [video]

#131

Post by mpweiher »

pclmulqdq wrote: post #129
mpweiher wrote: post #127

Earlier quoted context omitted.

Nope. > Read the IFT-3 pre-flight materials I did. > They clearly intended to enter an orbital trajectory and then get out of it Nope, they very clearly did not. Even the graphic you linked to earlier shows this very clearly. https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi... 1. At step 4 for Starship, they write "Once S28 has reached orbital velocity ..." Not trajectory . Not orbit . 2. At step 8, we ha…

Orbital velocity = orbital speed + orbital trajectory. Velocity is a vector. Orbital velocity + orbital altitude means orbit. That is, unless you think that everyone at SpaceX misspoke and they were only aiming for orbital speed (which they did not achieve with IFT3), and just wanted that speed in any direction. Sounds like the plan to de-orbit was then to just go belly forward and let drag take you out of orbit. Tha…

Once again: no.

The trajectory was suborbital, the perigee was inside earth so the actual trajectory would intersect the earth's surface, and the atmosphere first.

Re: Starship's Fourth Flight Test [video]

#132

Post by sbuttgereit »

pclmulqdq wrote: post #128
enslavedrobot wrote: post #125

Earlier quoted context omitted.

You do not rely on drag to deorbit a stainless steel 10 story building partially covered in heat shielding in a random location. They deliberately selected a suborbital trajectory with a velocity that matched orbital reentry... See 1:20 of this video. Everyone who actually follows SpaceX knows this. You are confidently and totally wrong. https://youtu.be/LOerY66mrPc?si=5FUAARFQ3Z98eqjb

All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. If you look at the GAO report on Artemis, one of the big issues they mentioned is that Starship has not proven that it can reach orbit, and SpaceX is very interested in making sure that the narrative is that it can and did. It was only after the fact that they said tha…

> All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity.

Given that the video was posted 4 days prior to that test, it is downright prescient that they are parroting a post-hoc rationalization.

Re: Starship's Fourth Flight Test [video]

#133

Post by pclmulqdq »

mpweiher wrote: post #131
pclmulqdq wrote: post #129

Earlier quoted context omitted.

Orbital velocity = orbital speed + orbital trajectory. Velocity is a vector. Orbital velocity + orbital altitude means orbit. That is, unless you think that everyone at SpaceX misspoke and they were only aiming for orbital speed (which they did not achieve with IFT3), and just wanted that speed in any direction. Sounds like the plan to de-orbit was then to just go belly forward and let drag take you out of orbit. Tha…

Once again: no. The trajectory was suborbital, the perigee was inside earth so the actual trajectory would intersect the earth's surface, and the atmosphere first.

The trajectory of the actual flight was suborbital, but the planned trajectory of the flight involved burning all the way to orbital insertion (hence the "orbital velocity" being on the flight plan). Once again, velocity is a vector, and "orbital velocity" means "a heading and speed suitable for orbit."

By the way, I agree that they never intended to complete an orbit, just that they intended to get into (and promptly out of) an orbit. IFT4 did that, for example.

After IFT3 failed to achieve orbital insertion (probably because a leak caused it to run out early), SpaceX announced that not only was the plan to not get to an orbit, but also that they had achieved orbital velocity. They claimed both things!

Both of those claims seem to be lies, and it is also logically inconsistent to claim that you never wanted to reach orbital velocity and also that you got there.

Re: Starship's Fourth Flight Test [video]

#134

Post by pclmulqdq »

sbuttgereit wrote: post #132
pclmulqdq wrote: post #128

Earlier quoted context omitted.

All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. If you look at the GAO report on Artemis, one of the big issues they mentioned is that Starship has not proven that it can reach orbit, and SpaceX is very interested in making sure that the narrative is that it can and did. It was only after the fact that they said tha…

> All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. Given that the video was posted 4 days prior to that test, it is downright prescient that they are parroting a post-hoc rationalization.

Just watched it, I had my dates mixed up. The trajectory this guy drew on the map does not involve starship reaching orbital velocity anywhere on it, which is inconsistent with SpaceX's publications. SpaceX's claim was that IFT3 would enter an orbit and then leave it, not that it would follow a ballistic trajectory to the indian ocean.

It's possible that SpaceX made the mistake of using the words "orbital velocity" and this YouTuber is right, though.

Re: Starship's Fourth Flight Test [video]

#135

Post by [deleted] »

sbuttgereit wrote: post #132
pclmulqdq wrote: post #128

Earlier quoted context omitted.

All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. If you look at the GAO report on Artemis, one of the big issues they mentioned is that Starship has not proven that it can reach orbit, and SpaceX is very interested in making sure that the narrative is that it can and did. It was only after the fact that they said tha…

> All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. Given that the video was posted 4 days prior to that test, it is downright prescient that they are parroting a post-hoc rationalization.

[deleted]

Re: Starship's Fourth Flight Test [video]

#136

Post by sbuttgereit »

pclmulqdq wrote: post #128
enslavedrobot wrote: post #125

Earlier quoted context omitted.

You do not rely on drag to deorbit a stainless steel 10 story building partially covered in heat shielding in a random location. They deliberately selected a suborbital trajectory with a velocity that matched orbital reentry... See 1:20 of this video. Everyone who actually follows SpaceX knows this. You are confidently and totally wrong. https://youtu.be/LOerY66mrPc?si=5FUAARFQ3Z98eqjb

All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. If you look at the GAO report on Artemis, one of the big issues they mentioned is that Starship has not proven that it can reach orbit, and SpaceX is very interested in making sure that the narrative is that it can and did. It was only after the fact that they said tha…

I think I'll end with this from Scott Manley, who I think communicates the most reasonable point in this regard. https://youtu.be/8htMpR7mnaM?si=z6UlTM5qC2feP-dM&t=420

So there... you're vindicated :-)

Re: Starship's Fourth Flight Test [video]

#137

Post by Manabu-eo »

pclmulqdq wrote: post #134
sbuttgereit wrote: post #132

Earlier quoted context omitted.

> All I see is a video from after IFT-3 that parrots SpaceX's post-hoc rationalization about the fact that their craft could not reach orbital velocity. Given that the video was posted 4 days prior to that test, it is downright prescient that they are parroting a post-hoc rationalization.

Just watched it, I had my dates mixed up. The trajectory this guy drew on the map does not involve starship reaching orbital velocity anywhere on it, which is inconsistent with SpaceX's publications. SpaceX's claim was that IFT3 would enter an orbit and then leave it, not that it would follow a ballistic trajectory to the indian ocean. It's possible that SpaceX made the mistake of using the words "orbital velocity" a…

> SpaceX's claim was that IFT3 would enter an orbit

You are claiming that, SpaceX never claimed that, only "orbital velocity" meaning "orbital speed" in this context. They wanted to test if the Starship is capable of reaching orbit, but w/o entering orbit for safety reasons. For that they wanted to achieve "orbital velocity" but of course not in an "orbital trajectory".

Re: Starship's Fourth Flight Test [video]

#138

Post by [deleted] »

pclmulqdq wrote: post #129
mpweiher wrote: post #127

Earlier quoted context omitted.

Nope. > Read the IFT-3 pre-flight materials I did. > They clearly intended to enter an orbital trajectory and then get out of it Nope, they very clearly did not. Even the graphic you linked to earlier shows this very clearly. https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi... 1. At step 4 for Starship, they write "Once S28 has reached orbital velocity ..." Not trajectory . Not orbit . 2. At step 8, we ha…

Orbital velocity = orbital speed + orbital trajectory. Velocity is a vector. Orbital velocity + orbital altitude means orbit. That is, unless you think that everyone at SpaceX misspoke and they were only aiming for orbital speed (which they did not achieve with IFT3), and just wanted that speed in any direction. Sounds like the plan to de-orbit was then to just go belly forward and let drag take you out of orbit. Tha…

[deleted]

Re: Starship's Fourth Flight Test [video]

#139

Post by Manabu-eo »

pclmulqdq wrote: post #133
mpweiher wrote: post #131

Earlier quoted context omitted.

Once again: no. The trajectory was suborbital, the perigee was inside earth so the actual trajectory would intersect the earth's surface, and the atmosphere first.

The trajectory of the actual flight was suborbital, but the planned trajectory of the flight involved burning all the way to orbital insertion (hence the "orbital velocity" being on the flight plan). Once again, velocity is a vector, and "orbital velocity" means "a heading and speed suitable for orbit." By the way, I agree that they never intended to complete an orbit, just that they intended to get into (and promptl…

You are overlooking the easier explanation: they used "velocity" in the more colloquial sense meaning speed, not in the vector sense. Suddenly everything is logically consistent.

And everything matches what they said, what they filled with FAA prior to the fight, etc.

Re: Starship's Fourth Flight Test [video]

#140

Post by slimebot80 »

openmarmot wrote: post #77
slimebot80 wrote: post #42

This will be crammed into my Twitter feed relentlessly. Unlike today's successful Boeing launch, which wasn't in the feed or any trending topics whatsoever. Twitter is only a news source for topics with benefits.

Boeing launch was yesterday. Every space account on X was talking about it. The ULA, Boeing, and NASA accounts were all posting about it. Elon retweeted the livestream and wished them luck : https://x.com/elonmusk/status/1798338630471364871 He also congratulated them and retweeted a follow up post from Nasa Kennedy Space center.

Yes! my point exactly. Amazing how these posts are stifled and disappear quickly. Yet, multiple culture warrior / dogecoin accounts posting a spacex rocket photo gets pumped into my timeline.
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