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Old May 21st 19, 03:53 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Default NASA's full Artemis plan revealed: 37 launches and a lunar outpost

JF Mezei wrote on Mon, 20 May 2019
19:37:57 -0400:

On 2019-05-20 17:58, Fred J. McCall wrote:

First, nobody is asking for "unlimited budgets". Second, I'm not
convinced that THIS plan is executable even if they give them all the
money


That was the crux of my question. aka: when budget is not an issue, can
they do it ?


Then you need to ask what you want to know without trying to 'spin'
the question with your politics. Personally, I don't think they can
get all the pieces done and in place by 2024.

Falcon Heavy just doesn't have the 'grunt' for the sort of mission
architecture that NASA has fixed on.


Siome of the NASA pictures showed different components launched
separately. Doesn't that give Falcon Heavy (or even Falcon 9) a means
to get the "stack" in orbit before it goes to the moon with all the fuel
it needs?


Pieces have to be just pretty damned small to do it with Falcon Heavy.
Nothing over 10 tonnes.


For SpaceX it woudl essentially be practice runs for the various systems
such as refueling, docking in orbit etch that would allow BFR/BFS to
launch and then multiple BFR launches to fuel BFS.


One more time. Things that are different just are not the same.
Nothing done would be applicable to BFR/BFS.

In fact, SLS Block 1 is short by
around 10 tonnes of having enough power for these missions. Block 1B
is required and that's essentially under a 'stop work' until Block 1
is completed.


Does Block 1B translate to new/updated engines, or would they uprate the
existing leftover SSMEs? In the case of the 6 new SSMEs that are being
produced, those are block 1s?


Oh, good Lord! Do you ever bother to find out even the most trivially
available things before you hang your hat on some preposterous notion?
There is no 'uprating' of the RS-25s between SLS Blocks, so all your
arm flapping is moot. Here is the difference. To get from Block 1 to
Block 1B the Interim Upper Stage is replaced by the Exploration Upper
Stage. To get from that to Block 2 you replace the SRBs with
something called the 'Advanced Booster'. This is still in study.

Where did you get that they only have a single set of SSMEs left?


16 engines = 4 SLS flights. So I was saying wthere NASA could do 3 tests
and use the last set to go to the moon. Or whether they need more sets
to get from a "never flown" to "boots on the moon".


That's not what you originally said. So you agree that they have FOUR
sets of engines left and not the single one you originally claimed.
Under the plan to get people on the Moon by 2024 the third flight of
SLS in 2024 does that. So after you put people back on the Moon you
STILL have a set of engines to fly the 2025 mission with.


We know first flight is unmanned. So that leaves 2 test flights before
a final set of engines can do the mission to the moon.


Except that doesn't get you there by 2024.


So if NASA will absolutely need more engines to make 2024 deadline, ...


They won't. Stop flapping your arms.


... how
come those 11 contracts don't include the contract extension to build
more than 6 SSME? Unless, of course, NASA knows it won't use SLS and
will use commercial to get the job done.


Because they won't need any new engines until 2026.

No. Do you not follow any news at all? NASA just recently let
contracts to 11 different companies to study and, in some cases, build
prototypes of pieces of their lander architecture.


Studies and prototypes. Does that really leave enough time to build/test
the damned thing for 2024 moonshot?


You've got to start somewhere. That is the first step. Did you
notice the duration of those contracts? Six months.


I am curious on the process where the VP was given indications that 2024
was doiable, or whether he knows it isn't realistics, but political
considerations made him make Nasa starts that undoiable project knowing
it will fail during the opposition party,s tenure at White House.


You're 'curious', all right. Curiously retarded by your Trump
Derangement Syndrome.

What eliminates the LEM is that you would have to totally rebuild an
industrial base to produce it. It's probably faster and cheaper to go
with a 'clean sheet' design that uses currently existing industry.


Don't you have to do the same for any design since it is starting from
scratch? It isn't likie buying some off the shelf car and then souping
it up like the pimp mobile Austin Powers uses to travel back in time.


When you do a design you design to **** we already build and that you
can get manufactured. When you trot out a half century old design you
don't have that luxury. You have to both do a redesign AND engage to
get a bunch of old **** that's no longer part of the industrial base
spooled up.


Forgetting science fiction which inflences those making pretty 3D
designs for powerpoints shown to politicians, wasn't the LEM design
optimized very well for the mission? Wouldn't a similar mission not end
up designing something similar?


Nothing in that paragraph makes any sense, but let me provide your
answers. Easy to forget things that don't exist. No. No.


Knowing more about lunar surface, would the landing gear be very
different or pretty much the same?


Yes.

It doesn't matter, since hypergolic engines aren't a requirement. Blue
Moon, for instance, uses LH2/LOX.


I assume those would be kept in high pressure tanks since they have to
be kept days with wildly varying temperatures?


Assume what you like, but remember what it means.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw