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Falcon Heavy Launch [video]

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Re: Falcon Heavy Launch [video]

#241

Post by dotnet00 »

usrusr wrote: post #226
dotnet00 wrote: post #33

Earlier quoted context omitted.

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…

When I skipped through the video to the point where they explain that this was a mission without center reuse I was surprised to hear that they actually do seem to offer a three booster reuse profile. Perhaps my surprise was from confusing "no second stage reuse" with "no center booster reuse"? But if it's a wash (as you say) between non-reusable F9 and 3x reusable FH I'd probably go for a single EOL core anyways, fo…

Yeah, I understood that, I just enjoy talking about the contrast between F9 and FH and how F9 improved so much that it mostly took over FH's market :P

Eric Berger also put out a pretty good piece talking about all of this yesterday: https://arstechnica.com/science/2022/10/the-worlds-most-powe...

Re: Falcon Heavy Launch [video]

#242

Post by comeonbro »

misiti3780 wrote: post #54
thallium205 wrote: post #46

Earlier quoted context omitted.

And the fact it will cost about 10x as much compared to SpaceX rockets to deliver something to orbit. SLS is a total failure.

It's amazing how many people hold this opinion (OP) when it could be resolved with < 1 minute of research.

Ideological commitments that could be resolved with < 1 minute of research, will not be resolved with < 1 minute of research.

Re: Falcon Heavy Launch [video]

#243

Post by pleo__ »

bell-cot wrote: post #128
pfdietz wrote: post #105

Earlier quoted context omitted.

If you watched the liftoff, after the vehicle was above the fog, the plume from the core looked much weaker than from the boosters. I think they throttle that stage down so it's using less fuel, leaving fuel to be burned after the boosters are done. This will also reduce the velocity at which the boosters are staged so they have an easier time getting back. After the boosters stage the core will be throttled back up…

Correct, and that throttle-fiddling is required to get a good performance boost from using side boosters.

Additionally, the center core is throttled to make sure the vehicle safely gets through the dangerous "max-Q" part of the launch where stress from the atmospheric drag is highest.

Re: Falcon Heavy Launch [video]

#244

Post by nrb »

nwah1 wrote: post #202
nrb wrote: post #92

Earlier quoted context omitted.

Research how and where SLS must be designed, manufactured, integrated, and tested. Then research who designated that process and how. Calling Falcon Heavy and SLS equivalently government-led is laughable. The amount of by-design government red tape and congressional district handouts is astounding.

SLS is a joint project between many large bureaucratic private organizations, and thus design-by-committee is more of a function of the way that those institutions operate, and their need to coordinate with one another. Congress cared that it met payload requirements and mission requirements. That these institutions were unable to deliver within reasonable time and budget limits is a result of their own dysfunction.…

> Congress cared that it met payload requirements and mission requirements.

This is just not correct if you mean that they only cared about payload and mission requirements. Congress mandated that certain technologies were to be used from non-competitive, single-source suppliers in order to prop up industry in particular congressional districts. Cost overruns are practically by-design because as long as it doesn’t raise too many eyebrows it’s just more money to their local industry and constituents.

Re: Falcon Heavy Launch [video]

#245

Post by mr_sturd »

gpm wrote: post #219
mr_sturd wrote: post #199

Earlier quoted context omitted.

Makes you wonder if this customer actually did though. If they were forced to dispose of the central booster due to the needs of the payload, that central booster must be costed in.

They paid more, something like $150M I think "no one pays that" has more to do with "every mission is actually a negotiated contract" than "the price is inflated". https://www.nasaspaceflight.com/2022/10/falcon-heavy-ussf-44...

Fair enough, I'd naïvely thought of it as a ceiling.

Re: Falcon Heavy Launch [video]

#246

Post by wumpus »

wiredfool wrote: post #16
usrusr wrote: 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.~

> What they're doing with the second boost, they're not telling anyone.

This is a direct-to-GEO launch, and some of the payloads are public.

Re: Falcon Heavy Launch [video]

#247

Post by zasdffaa »

chipsa wrote: post #222
zasdffaa wrote: post #213

Did I miss something or did this rocket have no stack - it was a single stage (with boosters, but aside those still one undivided rocket)? Can anyone comment on that please.

It's side boosters, center booster, and second stage. But the second stage is the same diameter as the boosters, so you can't easily see the difference if you don't know what to look for.

I see. Seems rocket engine efficiency must have seriously improved while I was not looking, thanks.

Re: Falcon Heavy Launch [video]

#248

Post by polytely »

booboofixer wrote: post #45

When does/do the research/space programs enabled by these more frequent launches start to benefit us all? It must have already contributed to something somehow. Agriculture? Defense? Oil exploration? Seems like the sort of information that's hard to find.

it's more just lowering the price of getting things to orbit, so there are certain thresholds that will probably make new businesses viable.

Re: Falcon Heavy Launch [video]

#250

Post by jpadkins »

oorza wrote: post #115
chroma wrote: post #104

Earlier quoted context omitted.

It's probably more cost-effective to keep the craft and scrap it. The structure itself is a significant amount of steel, and the engines contain expensive superalloys.

If a spacefaring vessel lasts long enough that it needs to be decomissioned due to wear and tear, that mf'er belongs ONLY in a museum. I hope to live to the day where that isn't universally true, but it is not today.

SpaceX would get considerably more than $10M in marketing / brand goodwill by donating to a museum. So for the first 1 or 2 decommissioned rockets, I think donation beats scrap ROI.
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