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Space X 2nd stage recovery



 
 
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  #21  
Old April 25th 18, 11:35 AM posted to sci.space.policy
Jeff Findley[_6_]
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Default Space X 2nd stage recovery

In article ,
says...

"JF Mezei" wrote in message ...

On 2018-04-24 07:10, Jeff Findley wrote:

I'm glad they're working on upper stage recovery. My guess is that
BFR/BFS will take a bit longer than Elon's aspirational schedule
products.



If SpaceX truly stops production of Merlin engine as it moves its
operatiosn to BFR/BFS, despite recovering stage 1s, won't they
eventually run out of engines for stage 2?


I suspect they'll keep building engines for awhile, simply to have enough
and to build in improvements.
But the rate will probably decrease.


Improvements are pretty much over for Merlin. The Block 5 confguration
is the last for Falcon. They have to standardize due to NASA's crewed
requirements for Dragon 2. Any changes would require a lengthy and
costly recertification process.


or will SpaceX in reality continue to produce the engines at least for
the upper stage config ?

If they can recover stage 2 engines reliably, this could enable ending
production of the engines to retool for BFR/BFS ?


Eh, I'm not sure it's a huge problem.


Me either, especially since they're building a new factory specifically
for BFR/BFS production. It's been all over the news.

Jeff
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  #22  
Old April 25th 18, 12:14 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Space X 2nd stage recovery

In article ,
says...

On 2018-04-24 07:10, Jeff Findley wrote:

I'm glad they're working on upper stage recovery. My guess is that
BFR/BFS will take a bit longer than Elon's aspirational schedule
products.



If SpaceX truly stops production of Merlin engine as it moves its
operatiosn to BFR/BFS, despite recovering stage 1s, won't they
eventually run out of engines for stage 2?

or will SpaceX in reality continue to produce the engines at least for
the upper stage config ?

If they can recover stage 2 engines reliably, this could enable ending
production of the engines to retool for BFR/BFS ?


I personally can't imagine Merlin production to completely stop until
after BFR/BFS is flying successfully. Same for Falcon production
especially due to the oddball expendable or partially expendable flight
due to performance reasons.

That said, SpaceX can certainly scale back production considerably once
Block 5 first stages/boosters are flying successfully, assuming it meets
its goals of 10 flights between refurbishments with 100 flights overall.
Reducing first stage/booster production by nearly a factor of 100 is
huge when it contains 9 Merlins and the upper stage only one.

Jeff
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  #23  
Old April 25th 18, 12:17 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Space X 2nd stage recovery

In article ,
says...

On 2018-04-24 07:10, Jeff Findley wrote:

They do, to pressurize the kerosene and LOX tanks for the Merlin engine.
Adding another gas would complicate pad operations (only a bit, but
still).



Wouldn't that require running additional piping up the launch tower and
new connection points on the rocket to load the gas into the tanks,
along with the pipe unhooking hardware at launch time?

Is that considered "major" or a no brainer type of work?


It's not so much the pad modifications, which are a one time cost.
Anything that complicates operations increases cost over time. SpaceX
is very cost conscious when it comes to operations. That's why they had
lower prices even before they started to recover and reuse first stages.

I saw a Tweet yesterday which said that Mr. Steven came back with both
fairing halves. Nothing official from SpaceX as of yet, but that's no
small bit of change either. Those things are several millions of
dollars of hardware and every other provider just disposes of them on
every single flight. A million here, a million there, and pretty soon
you're talking real money.

Jeff
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  #24  
Old April 25th 18, 12:20 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Space X 2nd stage recovery

In article , says...

On 4/24/2018 7:10 AM, Jeff Findley wrote:
I'm glad they're working on upper stage recovery. My guess is that
BFR/BFS will take a bit longer than Elon's aspirational schedule
products. As such, Falcon 9 and Falcon Heavy will remain the workhorses
of SpaceX for many years to come. Anything they can do to cut their
costs increases the cash they can funnel into BFR/BFS development.

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized. In a perfect world, a "white knight" would
step forward and say, "Look we love what you have flying already. And we
want to build our own (crewed) space program around it." That WK *could*
be NASA, but thanks to politics (and SLS) its likely going to have have
to be either business, academia or another country. Politics makes all
things complicated. But if an ally (like Australia) came forward, esp.
if they not only came with a checkbook but with a request for contract
to have SpaceX build an Australian launch complex with them....

But let's see what Bridenstein can pull off.


I'm putting little faith in significant changes at NASA over the next 3
to 7 years. And by significant, I mean at the very least canceling SLS.

What might be possible is Bigelow Aerospace finally launching a
commercial station. If they do that, they'll need crew and cargo
flights to keep it running. SpaceX will surely have the lowest costs,
partly due to reuse of Dragon 2 and partly because they're not Boeing.

Jeff
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All opinions posted by me on Usenet News are mine, and mine alone.
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  #25  
Old April 25th 18, 12:27 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default Space X 2nd stage recovery

In article ,
says...

On 2018-04-24 14:21, David Spain wrote:

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized.



Unless the space station life is extended beyond 2025, FH and Dragon2
may very well remain the workhorse for mnanned space in USA.


This makes no sense to me. ISS is the reason Dragon 2 and Starliner
were both built and will be flying within a year two with crew. Not
extending ISS beyond 2025 spells uncertainty for both Dragon 2 and
Starliner.

And unless there is real funding for manned space programme beyond ISS,
nobody will see much business case to invest in manned space programme
from now on, unless you go for it on your own (aka: SpaceX with BFR to
Mars).


Depends if they have a destination. A Bigelow Aerospace inflatable
space station could be a possible destination.

Where the "international" thing may fall in place is if SpaceX gets
serius about mars and other countries want "in" on the project,
supplying modules for the Mars colony or any other "help" they can
provide to SpaceX.


That's BFR/BFS not Dragon 2.

But unless a place like Australia could provide a huge cost and
logistics benefit to have SpaceX launch/land there, SpaceX might not be
so interested when you consider transportation logistics for modules
built in USA.


WTF are you trying to say here? SpaceX isn't bloody likely to launch
from anywhere but the US. As a US Company, they have to follow US
launch rules anyway. Shipping to Australia adds costs. Launching from
Australia adds costs. There is no upside here.

In the case of a LEO assembly/refueling spot to later go to Mars, would
launching from 12°S (northern Australia) offer significant performance
advantage over 28°N (Canaveral)?


A little, but not much. Certainly not enough to wipe out the added
costs of launching from somewhere Falcon and Dragon can't be driven
there by semi-truck, which is how they're transported today. That's why
Falcon is so tall and skinny. Any wider and transportation costs from
the factory to Texas test site to the launch site increases
significantly.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #26  
Old April 25th 18, 12:39 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 2,307
Default Space X 2nd stage recovery

In article ,
says...

JF Mezei wrote on Tue, 24 Apr 2018
16:36:20 -0400:

On 2018-04-24 14:21, David Spain wrote:

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized.


Unless the space station life is extended beyond 2025, FH and Dragon2
may very well remain the workhorse for mnanned space in USA.


So Boeing is irrelevant in your mind?


And unless there is real funding for manned space programme beyond ISS,
nobody will see much business case to invest in manned space programme
from now on, unless you go for it on your own (aka: SpaceX with BFR to
Mars).


The issue here is that Bigelow seems to have jumped in bed with ULA.
If that extends to ferrying supplies and 'guests' to 'space hotels',
they might not let SpaceX vehicles dock.


Where the "international" thing may fall in place is if SpaceX gets
serius about mars and other countries want "in" on the project,
supplying modules for the Mars colony or any other "help" they can
provide to SpaceX.


Or just people who want to go to Mars. If there are enough, it would
make sense to launch from almost anywhere.


I personally doubt that would happen very soon unless the flight rate of
BFR/BFS tops 100 per year (which I don't think will happen for a decade
or two). Despite SpaceX's pretty renderings of off-shore launch/landing
platforms, launch and landing sites still aren't cheap to build. I'd
think you'd need significant local investment in order to make a non-US
launch site profitable.


But unless a place like Australia could provide a huge cost and
logistics benefit to have SpaceX launch/land there, SpaceX might not be
so interested when you consider transportation logistics for modules
built in USA.


Remember, BFR Spaceship can do point to point travel on Earth and land
anywhere there's a big enough piece of concrete.


Yeah, paper rockets can do anything. SMH. I still have huge doubts
about the whole point to point thing. The A380 took five aircraft to
fly over 2000 hours in its testing phase. For BFR/BFS the same sort of
times would take well over 1000 flights. That's not happening in a
short period of time.

That and point to point only gets BFS to another part of the world.
Unless the booster can self ferry too, you still have the huge first
stage to transport by ship half way around the world. That's only going
to make sense if that remote site can support several Big Falcon
Boosters. One is just a single point of failure for your transportation
system. If it's in the hangar being worked on, it's not flying and
generating revenue.

Will we get there? Maybe, eventually. I'm a huge SpaceX "fan boy", but
let's get real. BFR/BFS hasn't even been built yet! Hell, Falcon 9
Block 5 hasn't even flown, let alone proven its reuse abilities!

All these visions of super cheap spaceflight are where we want to be,
but it's going to take a decade or two to get there, IMHO. Until then,
Falcon 9 and Falcon Heavy will be the "workhorses" of SpaceX.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #27  
Old April 25th 18, 03:51 PM posted to sci.space.policy
David Spain
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Default Space X 2nd stage recovery

On 4/24/2018 4:36 PM, JF Mezei wrote:
On 2018-04-24 14:21, David Spain wrote:

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized.



Unless the space station life is extended beyond 2025, FH and Dragon2
may very well remain the workhorse for mnanned space in USA.


Well you and I have somewhat different opinions of workhorses. Ferry
flights to ISS are all well and good. But unless an expansion of ISS in
in the works a flight rate of what, about 4 flights a year is more than
sufficient?

What about crewed LEO trips and/or Moon flybys for touristas? For that
matter a crewed scientific flyby mission to Venus? Scouting missions to
Martian moons even?

And unless there is real funding for manned space programme beyond ISS,
nobody will see much business case to invest in manned space programme
from now on, unless you go for it on your own (aka: SpaceX with BFR to
Mars).


Funding by whom? We're just about at that point. Which is my point.


Where the "international" thing may fall in place is if SpaceX gets
serius about mars and other countries want "in" on the project,
supplying modules for the Mars colony or any other "help" they can
provide to SpaceX.


That could happen. In fact, given the current trajectory of NASA,
probably even likely.


But unless a place like Australia could provide a huge cost and
logistics benefit to have SpaceX launch/land there, SpaceX might not be
so interested when you consider transportation logistics for modules
built in USA.


You are looking through the wrong end of the telescope. Australia would
hire SpaceX as a *vendor* to supply materials and technology for the
*Australian* space program. Huge benefit to not having to bootstrap it
all by yourself. You hire the best experts in the world. If not SpaceX,
then maybe Bezos' Blue Origin would oblige. Yes it's tech transfer, but
with a *buyer* whose funds (remember it has to be a *profitable*
proposal for SpaceX) could finance who knows what at SpaceX?

In the case of a LEO assembly/refueling spot to later go to Mars, would
launching from 12°S (northern Australia) offer significant performance
advantage over 28°N (Canaveral)?


Some. But setting Mars aside, for the inhabitants of Oz certainly! If it
helps clarify what I'm saying let's say the deal is between Australia's
equiv. of NASA and Blue Origin. Just to keep Mars confusion off the
table....

Dave
  #28  
Old April 25th 18, 06:56 PM posted to sci.space.policy
David Spain
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Default Space X 2nd stage recovery

On 4/24/2018 5:54 PM, Fred J. McCall wrote:
JF Mezei wrote on Tue, 24 Apr 2018
16:36:20 -0400:

On 2018-04-24 14:21, David Spain wrote:

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized.


Unless the space station life is extended beyond 2025, FH and Dragon2
may very well remain the workhorse for mnanned space in USA.


So Boeing is irrelevant in your mind?


Not to my mind. Which makes for even more infrequent flights to ISS by
SpaceX. Also doesn't require crewed F9H for any of these either.


And unless there is real funding for manned space programme beyond ISS,
nobody will see much business case to invest in manned space programme
from now on, unless you go for it on your own (aka: SpaceX with BFR to
Mars).


The issue here is that Bigelow seems to have jumped in bed with ULA.
If that extends to ferrying supplies and 'guests' to 'space hotels',
they might not let SpaceX vehicles dock.


Yes. That thought had crossed my mind as well. I hope not.


Where the "international" thing may fall in place is if SpaceX gets
serius about mars and other countries want "in" on the project,
supplying modules for the Mars colony or any other "help" they can
provide to SpaceX.


Or just people who want to go to Mars. If there are enough, it would
make sense to launch from almost anywhere.


But unless a place like Australia could provide a huge cost and
logistics benefit to have SpaceX launch/land there, SpaceX might not be
so interested when you consider transportation logistics for modules
built in USA.



I addressed this elsewhere. A contract that would allow some assembly in
Australia, some would be shipped out from US. Eventually Australia might
be supplying some of their own parts.

Remember, BFR Spaceship can do point to point travel on Earth and land
anywhere there's a big enough piece of concrete.


True once that happens. But I am purposely leaving BFR (and Mars) out of
it. Trying to make a case for why someone might be interested in
existing F9(H) or Blue Origin hardware.

Getting back to F9 and Dragon V2 specifically. Propulsive landing and
landing gear were removed from Dragon V2 at NASA's behest. But if there
were another 3rd party customer that wanted that capability, it'd be a
way to get a customer to invest in and help pay for the testing needed
to make it a reality.

[snipped]

I think all the inspection and such will occur at the launch site.
That makes locating the facility outside the US something of an ITAR
issue. I wouldn't expect Australia to be a problem, but you never
know...


Me either, that's why I used them as an example.

  #29  
Old April 26th 18, 06:15 PM posted to sci.space.policy
Greg \(Strider\) Moore
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Default Space X 2nd stage recovery

"JF Mezei" wrote in message ...

On 2018-04-25 07:27, Jeff Findley wrote:

This makes no sense to me. ISS is the reason Dragon 2 and Starliner
were both built and will be flying within a year two with crew. Not
extending ISS beyond 2025 spells uncertainty for both Dragon 2 and
Starliner.


I was refering to any new developments. Dragon and Starliner's
development costs are being paid by NASA and the flights to ISS till
2025. After that, those vehicles remain "available" if needed, but
there wouldn't be any justification to build anything new since
restarting Dragon or Starliner production would cost much less than
designing from new.


Depends if they have a destination. A Bigelow Aerospace inflatable
space station could be a possible destination.


And who pays for it? Do you have long term supply of space tourists
willing to pay $20m each?


Not many, which is why as you develop the infrastructure, you drop the
price.

Dragon 2 will seat 7. I believe it only needs 1 trained pilot, but let's
assume 2.
That's still 5 paying seats.

Falcon 9 prices are falling and the price you see quoted is the one to
"make a profit"
SpaceX's internal prices are probably far lower.

So once you sell out the $20M seats, you start to sell $15M and then $10M.

I wouldn't be surprised if SpaceX could go even lower and still make a
profit.

--

  #30  
Old April 26th 18, 09:21 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
Default Space X 2nd stage recovery

Jeff Findley wrote on Wed, 25 Apr 2018
07:39:46 -0400:

In article ,
says...

JF Mezei wrote on Tue, 24 Apr 2018
16:36:20 -0400:

On 2018-04-24 14:21, David Spain wrote:

I am of the opinion that the existing F9 and F9H architectures will be
(crew-wise) underutilized.


Unless the space station life is extended beyond 2025, FH and Dragon2
may very well remain the workhorse for mnanned space in USA.


So Boeing is irrelevant in your mind?


And unless there is real funding for manned space programme beyond ISS,
nobody will see much business case to invest in manned space programme
from now on, unless you go for it on your own (aka: SpaceX with BFR to
Mars).


The issue here is that Bigelow seems to have jumped in bed with ULA.
If that extends to ferrying supplies and 'guests' to 'space hotels',
they might not let SpaceX vehicles dock.


Where the "international" thing may fall in place is if SpaceX gets
serius about mars and other countries want "in" on the project,
supplying modules for the Mars colony or any other "help" they can
provide to SpaceX.


Or just people who want to go to Mars. If there are enough, it would
make sense to launch from almost anywhere.


I personally doubt that would happen very soon unless the flight rate of
BFR/BFS tops 100 per year (which I don't think will happen for a decade
or two). Despite SpaceX's pretty renderings of off-shore launch/landing
platforms, launch and landing sites still aren't cheap to build. I'd
think you'd need significant local investment in order to make a non-US
launch site profitable.


True. It would take some large group of people wanting to 'get out
from under', like the Pilgrims back in the past. Something that would
create an ongoing demand for launches and a combined fund to support
things. On the flip side of that is the limited launch window for
getting to Mars. You only get a window every couple of years, so you
need to launch all your ships in that window. I think Musk's current
'plan' is to send 1-2 ships the first window in 2022 and twice as many
in the next window.


But unless a place like Australia could provide a huge cost and
logistics benefit to have SpaceX launch/land there, SpaceX might not be
so interested when you consider transportation logistics for modules
built in USA.


Remember, BFR Spaceship can do point to point travel on Earth and land
anywhere there's a big enough piece of concrete.


Yeah, paper rockets can do anything. SMH. I still have huge doubts
about the whole point to point thing. The A380 took five aircraft to
fly over 2000 hours in its testing phase. For BFR/BFS the same sort of
times would take well over 1000 flights. That's not happening in a
short period of time.


Given what it is, I don't find BFR Spaceship being able to do this
peculiar or unreasonable at all. If BFR Spaceship is certified under
spacecraft rules for manned flight, I don't see any reason why it
would require any additional testing to operate 'point to point'.


That and point to point only gets BFS to another part of the world.
Unless the booster can self ferry too, you still have the huge first
stage to transport by ship half way around the world. That's only going
to make sense if that remote site can support several Big Falcon
Boosters. One is just a single point of failure for your transportation
system. If it's in the hangar being worked on, it's not flying and
generating revenue.


You're going to have to do that to get it from LA to the launch site
anyway. They're building these things in LA because they're too big
to move other than by ship. That means they're going down through
Suez to get to East Coast launch sites, so they're making a very long
ocean voyage anyway.


Will we get there? Maybe, eventually. I'm a huge SpaceX "fan boy", but
let's get real. BFR/BFS hasn't even been built yet! Hell, Falcon 9
Block 5 hasn't even flown, let alone proven its reuse abilities!


True, but either BFR Spaceship will have point-to-point capabilities
on Earth or it will be a complete and utter failure for its intended
purpose.


All these visions of super cheap spaceflight are where we want to be,
but it's going to take a decade or two to get there, IMHO. Until then,
Falcon 9 and Falcon Heavy will be the "workhorses" of SpaceX.


Well, I think Elon Musk is being optimistic as usual with his
'schedule'. He's said himself that five years seems like a terribly
long time to him, so he thinks anything ought to be able to be done in
five years. I personally think he's got around five years LEFT, so
perhaps he'll get a Mars flight off in 2024. Perhaps not.


--
"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
 




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