Author Topic: Discussion/Comparison of the new generation of American heavy lift launchers  (Read 7610 times)

Online envy887

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ITS was an interesting presentation.  I don't see it as a funded development effort at this point

It's partially funded, to the tune of 5% of SpaceX resources. But only F9, FH, SLS Block 1 and NG 2-stage are fully funded.

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while the others on my list are serious, funded development efforts as near as I can determine.
Vucan isn't fully funded, funds for it are approved quarterly. Neither is ACES, nor NGL, nor SLS Block 1B, or SLS Block 2. NG 3-stage might not be fully funded, Bezos hasn't made a definitive statement on the matter. If you preclude partially funded efforts, half the list is gone.

I don't know how you can doubt that SpaceX is serious about ITS (or something very similar). This is the very goal Musk et al have been struggling towards for the 15 years... They have invested enormous effort and aren't going to stop with this goal already in sight.

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Musk himself said that major government funding was needed for the ITS as it was presented.

No, he did not say that. What he said was:

Quote from: Elon Musk
There are also many people in the private sector who are interested in helping to fund a base on Mars, and perhaps there will be interest on the government sector side to do that too. Ultimately, this is going to be a huge public–private partnership.

The BASE will perhaps be partly or largely government funded; that is the part he needs help with. But the transport system he is willing to build himself. Government funds would be welcomed, but not at all strictly necessary:

Quote from: Elon Musk
I should also add that the main reason I am personally accumulating assets is in order to fund this. I really do not have any other motivation for personally accumulating assets except to be able to make the biggest contribution I can to making life multi-planetary.

Obviously "this" starts with the rocket to get there. Musk's net worth has been pointed out elsewhere, and based on his published statement he is willing to spend every cent he can get his hands on to move this project forward. And if you doubt his veracity, consider he has already done so, spending literally his last cent on it in the early days of SpaceX.

Online envy887

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Some more information on SLS payload capacity released today. Doesn't look like Block 2 will hit 50 tonnes to TLI or 40 tonnes to Mars. SLS Block 2 should be listed as 37,600 kg to TMI and 45,000 kg to TLI. Block 1B estimates appear to be pretty accurate though...
Note that the Block 2 numbers are given as "minimums".   Actual payload capabilities would likely exceed.
They likely would be higher with liquid boosters; the user guide assumes advanced SRBs (Black Knight?).

Online envy887

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Elon was talking about the most optimistic possible schedule, not the realistic schedule.

True. And Ed is adjusting schedules in his list to fit likely dates. None of the schedules are set in stone: the closest such thing is SLS, which was supposed to begin operational flights in 2016, but now likely won't until 2023.

Just adjust for Elon time dilation as necessary

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The "raptor" engine being tested is said to be subscale mode, not the actual engine.

Also true. But it was successfully all-up fired 9 months ago, while NG and Vulcan are still waiting on an engine that has only done powerpack testing so far, and is likely at least a year behind the sub-scale Raptor. Full-scale Raptor could easily be only a year behind BE-4 (meaning they would be doing full-scale powerpack testing right now) and on a nominal track to hit a 2020 first flight.

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And absolutely NOTHING has yet been done for launch, manufacturing or testing sites of BFR/ITS. Manufacturing ITS/BFR at Hawthorne would be very problematic due logistics, and they have no pad that they can use for BRF/ITS in the near future.

This is easily the best point to how far out ITS is, though I wouldn't say "nothing". They can obviously build and test components, but assembling and testing whole stages is a major issue, and 39A clearly has other priorities for the next few years. Right now ITS facilities are at least a year behind NG with a growing gap. But NG is still planning a test launch in 2019, so a 2020 ITS test launch isn't entirely impossible.

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(LC-39A is not an option for many years even though it's in the video)

BO has LC-36 and a new manufacturing facility is being constructed near it.

Maybe. People keep saying this about 39A, but

Quote from: Elon Musk
The thrust level is enormous. We are talking about a lift-off thrust of 13,000
tons, so it will be quite tectonic when it takes off. However, it does fit on Pad 39A, which NASA has been kind enough to allow us to use because they oversized the pad in doing Saturn V. As a result, we can use a much larger vehicle on that same launchpad.

I seriously doubt you know more about the subject than he does. And he says it three times in a row, so there's no possible alternative explanation except that he's flat out wrong. Which is certainly possible, but I have yet to see one shred of actual evidence supporting that explanation.

Edit: fix quotes
« Last Edit: 06/17/2017 02:42 AM by envy887 »

Online gongora

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Here's a direct quote for you:
Elon Musk, June 16 2017: "Major changes to the plan coming soon."  Can we please just stop the arguing about whether last September's ITS vehicle belongs on the list until after we hear Elon's update?

Online envy887

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Here's a direct quote for you:
Elon Musk, June 16 2017: "Major changes to the plan coming soon."  Can we please just stop the arguing about whether last September's ITS vehicle belongs on the list until after we hear Elon's update?

https://twitter.com/elonmusk/status/875770056323420160

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Mars V2 plan coming soon, which I think addresses the most fundamental flaw in V1: how to pay for development & operation of giant rockets

Considering the "giant rockets" part, I don't see any plausible interpretation of these statement that indicates the plan is anything other than a "new generation of American heavy lift launcher". Even if the details of the ITS implementation change somewhat, its discussion here is still relevant, on topic, and constructive not to mention interesting and generally quite civil. That's more than you can say for most threads around here :D

After all, the exact details of most (all?) these vehicles are still in considerable flux and most are educated guesses at best (notice all the question marks...). I think a set of placeholder values for ITS is appropriate.

Offline edkyle99

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After all, the exact details of most (all?) these vehicles are still in considerable flux and most are educated guesses at best (notice all the question marks...). I think a set of placeholder values for ITS is appropriate.
After SpaceX provides more information in (presumably) September.

 - Ed Kyle

Offline rsdavis9

After all, the exact details of most (all?) these vehicles are still in considerable flux and most are educated guesses at best (notice all the question marks...). I think a set of placeholder values for ITS is appropriate.
After SpaceX provides more information in (presumably) September.

 - Ed Kyle
https://twitter.com/elonmusk/status/875913504451985411
Tweet says:

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So soon you wont believe it
bob

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