Author Topic: SpaceX Rocket  (Read 24995 times)

Kim

  • Timelord
    • Fediverse
Re: SpaceX Rocket
« Reply #225 on: 19 November, 2023, 04:50:19 pm »
Watching it, it looked as if the Starship had also had a rapid unscheduled disassembly too, several minutes before they acknowledged that they'd lost it too.  Big white flash, not as big as the Booster one, but still quite bright.
The Booster had two thirds of its engines running before it gave up. The other third were all together.  I guess that would cause it to tumble violently. Falcon doesn't run all of the first stage engines at that point, so I wonder whether Booster was supposed to be running so many.

According to everyday astronaut, it was supposed to run 3 at that stage...

Presumably it runs the central three at minimal thrust during staging to keep the liquid propellant at the firey end of the Starship.

That the booster lost several engines in a cluster immediately after staging suggests that perhaps the sudden deceleration had the opposite effect on the booster.  Or it just broke something.  The flip manoeuvre appeared to be going okay until that point.  (I'm sure the re-light of the additional engines was intentional.)

quixoticgeek

  • Mostly Harmless
Re: SpaceX Rocket
« Reply #226 on: 19 November, 2023, 05:26:37 pm »
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Re: SpaceX Rocket
« Reply #227 on: 19 November, 2023, 10:37:26 pm »
Watching it, it looked as if the Starship had also had a rapid unscheduled disassembly too, several minutes before they acknowledged that they'd lost it too.  Big white flash, not as big as the Booster one, but still quite bright.
The Booster had two thirds of its engines running before it gave up. The other third were all together.  I guess that would cause it to tumble violently. Falcon doesn't run all of the first stage engines at that point, so I wonder whether Booster was supposed to be running so many.

According to everyday astronaut, it was supposed to run 3 at that stage...

Presumably it runs the central three at minimal thrust during staging to keep the liquid propellant at the firey end of the Starship.

That the booster lost several engines in a cluster immediately after staging suggests that perhaps the sudden deceleration had the opposite effect on the booster.  Or it just broke something.  The flip manoeuvre appeared to be going okay until that point.  (I'm sure the re-light of the additional engines was intentional.)
My limited reading about the apollo missions indicated that dealing with the 'lash', when cutting thrust between stages, was one of the most difficult problems to solve.
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Jaded

  • The Codfather
  • Formerly known as Jaded
Re: SpaceX Rocket
« Reply #228 on: 19 November, 2023, 10:41:45 pm »
Watching it, it looked as if the Starship had also had a rapid unscheduled disassembly too, several minutes before they acknowledged that they'd lost it too.  Big white flash, not as big as the Booster one, but still quite bright.
The Booster had two thirds of its engines running before it gave up. The other third were all together.  I guess that would cause it to tumble violently. Falcon doesn't run all of the first stage engines at that point, so I wonder whether Booster was supposed to be running so many.

According to everyday astronaut, it was supposed to run 3 at that stage...

Presumably it runs the central three at minimal thrust during staging to keep the liquid propellant at the firey end of the Starship.

That the booster lost several engines in a cluster immediately after staging suggests that perhaps the sudden deceleration had the opposite effect on the booster.  Or it just broke something.  The flip manoeuvre appeared to be going okay until that point.  (I'm sure the re-light of the additional engines was intentional.)
My limited reading about the apollo missions indicated that dealing with the 'lash', when cutting thrust between stages, was one of the most difficult problems to solve.

A shame it has not been solved yet….
It is simpler than it looks.

DaveJ

  • Happy days
Re: SpaceX Rocket
« Reply #229 on: 19 November, 2023, 11:22:33 pm »
The Apollo astronauts talked about that, going from multiple Gs to weightless and back to multiple Gs.  I think that there is more throttle control with the Raptors now than they had with the F1 engines back then, so maybe less of an issue.  Anyway, this time they kept three of the Booster Raptors running through staging.

The Booster has a more complicated problem, in that it turns 180 degrees immediately after staging before the boostback burn.  I've seen some speculation about fuel sloshing around leading to some of the engines running dry.