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Falcon Heavy Launch [video]

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Re: Falcon Heavy Launch [video]

#32
post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

>"wasteful to see that mission profile with the center booster burning up without even trying." My understanding was that the intended orbit / mission profile means that they must fly the center core in expendable mode. Otherwise, the satellite wouldn't be able to reach the intended orbit with the intended amount of fuel for the mission's duration.

Hopefully once Starship launches, we'll never see a disposable core again.

Re: Falcon Heavy Launch [video]

#33
post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

I think that due to how much F9 has managed to eat into FH's market, FH flights we see are more likely to only happen when the payload is heavy enough to need the center core to be expended.

For example, for a GTO insertion, an expended F9 can do 8.3t while a completely reusable FH can do 8t, but the expended F9 is going to be cheaper overall. Thus FH is only worth using when the payload is heavy enough to require at least the center core to be spent. This might be different for Lunar payloads though.

Re: Falcon Heavy Launch [video]

#35
post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

Edit: Units... I'd be the one going in mph through the surface of mars. ~The booster was going 12km/sec at MECO, which is more than escape velocity. What they're doing with the second boost, they're not telling anyone.~

Isn't orbit tracking trivial? Also, orbital velocity depends on altitude, so perhaps they are just going to a higher orbit.

Re: Falcon Heavy Launch [video]

#37
post #22
post #9

Did the center booster land? What timecode was that at?

i believe the orbit and mass requirement meant there was no fuel left for landing the center stage. I think the configuration where they can't re-use the booster is called "full thrust".

Or ... "max waste" ... no harm being honest about it and keeing peoples eyes on the prize!

Re: Falcon Heavy Launch [video]

#38

Earlier quoted context omitted.

>"wasteful to see that mission profile with the center booster burning up without even trying." My understanding was that the intended orbit / mission profile means that they must fly the center core in expendable mode. Otherwise, the satellite wouldn't be able to reach the intended orbit with the intended amount of fuel for the mission's duration.

Hopefully once Starship launches, we'll never see a disposable core again.

They are different classes of launch vehicles. This payload is not really a good one for starship, and conversely, starlinks will never fly on heavy

Re: Falcon Heavy Launch [video]

#40
post #2

The couple seconds of tracking camera footage of the boosters coming back down looked amazing. I wish it wasn't so foggy at the pad! When the second stage separates there's a few cables that are flying around. Does anyone know what those are used for? Electrical connections between the stages maybe?

I'm guessing you're referring to the stiffener that helps the second stage engine's nozzle hold its shape?

no not the stiffener but in the shot were you can see the stiffener at stage separation you can see the cables flying around too.
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