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  #11  
Old May 11th 17, 05:12 PM posted to sci.space.policy
Scott M. Kozel[_2_]
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Posts: 136
Default RD-180 relplacement

On Thursday, May 11, 2017 at 8:42:25 AM UTC-4, Fred J. McCall wrote:

"Scott M. Kozel" wrote:

Three separate heavy lift vehicles in development that
would be capable of taking men to the Moon or Mars.


Actually only one 'program'. And two commercial efforts.

I don't really understand that. Last time one vehicle was
developed and they built 16 of them and had programs in
place to use them within a reasonable period of time, that
provided economies of scale and focus to do the program.
It was a national scale program and accomplished great
things.


Last time we had a single government program that spent money like
water, made the trip, and then had no follow-on, which is why we can't
get beyond LEO anymore.

The current approach doesn't make sense; too many vehicle
types in development and no real focus toward building
enough of them to have an actual program.


The 'government program' (how we did Apollo) is the high priced
spread. It's true that it makes no sense because it has no real goal
(it changes with every President) and is too expensive to fly. The
other two efforts are commercial efforts, make more sense, spend a lot
less money, and will be far cheaper to fly.

If we did it the old way, we would ONLY have SLS, Musk and Bezos would
keep their money, and we'd get another 'flags and footprints' mission
to somewhere at best.


What kind of commercial effort for such a vehicle and program
could provide the tens of billions of dollars in private capital
to fund it? What would be the business model?

The federal government could provide 60-80% of the funding, but
that would not be a private sector effort, that would be massive
subsidization by the government.

Sure Apollo was expensive, but I wonder how the private sector
could profitably fund a program like that.
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  #12  
Old May 11th 17, 07:26 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 9,552
Default RD-180 relplacement

r"Scott M. Kozel" wrote:

On Thursday, May 11, 2017 at 8:42:25 AM UTC-4, Fred J. McCall wrote:

"Scott M. Kozel" wrote:

Three separate heavy lift vehicles in development that
would be capable of taking men to the Moon or Mars.


Actually only one 'program'. And two commercial efforts.

I don't really understand that. Last time one vehicle was
developed and they built 16 of them and had programs in
place to use them within a reasonable period of time, that
provided economies of scale and focus to do the program.
It was a national scale program and accomplished great
things.


Last time we had a single government program that spent money like
water, made the trip, and then had no follow-on, which is why we can't
get beyond LEO anymore.

The current approach doesn't make sense; too many vehicle
types in development and no real focus toward building
enough of them to have an actual program.


The 'government program' (how we did Apollo) is the high priced
spread. It's true that it makes no sense because it has no real goal
(it changes with every President) and is too expensive to fly. The
other two efforts are commercial efforts, make more sense, spend a lot
less money, and will be far cheaper to fly.

If we did it the old way, we would ONLY have SLS, Musk and Bezos would
keep their money, and we'd get another 'flags and footprints' mission
to somewhere at best.


What kind of commercial effort for such a vehicle and program
could provide the tens of billions of dollars in private capital
to fund it? What would be the business model?


A classic government engine development effort costs around $1.5
billion. Bezos is developing New Glenn, engines and all, for that
amount of money. He's funding it (and most of the rest of Blue
Origin) by selling a billion dollars of his Amazon stock every year.
Bezos is worth around $81 billion. Meanwhile, Musk is only worth
around $16 billion, so he's not funding it all with personal checks
like Bezos is. He's funding a lot of it now by undercutting the rest
of the world on launch costs.


The federal government could provide 60-80% of the funding, but
that would not be a private sector effort, that would be massive
subsidization by the government.


Bezos is funding BE-4 out of his own pocket. USAF is funding AR-1
development. BE-4 will be cheaper to buy (by a lot) and the
government isn't paying to develop it. Meanwhile Musk is getting
around $34 million from USAF to develop Raptor (while putting up $68
million of his own money). I wasn't kidding when I said that private
commercial development costs an order of magnitude less than
government funded development.


Sure Apollo was expensive, but I wonder how the private sector
could profitably fund a program like that.


It wouldn't. It would get the same results for a lot less money and
then sell missions to anyone who wanted them. Note that USAF has gone
down this road now. They don't generally develop rockets. They just
buy launch services. No reason NASA can't do the same. Or anyone
else, for that matter. The entire budget for New Glenn is what it
costs the government to develop an engine. I don't know what they'll
charge for a launch. Look at SpaceX launch costs compared to Atlas or
Delta. Estimates for SpaceX ITS is around $10 billion to develop with
a launch cost of around $63 million. SLS development is about twice
that to complete Phase I and costs almost a billion dollars per
launch.


--
"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
  #13  
Old May 11th 17, 11:41 PM posted to sci.space.policy
Bob Haller
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Default RD-180 relplacement

On Tuesday, May 9, 2017 at 4:28:12 PM UTC-4, Fred J. McCall wrote:
I'm confused. The program to replace the RD-180 is focused on engines
with around 400,000 lb thrust at sea level. This focuses them on the
AR-1 (kerosene/LOC) and BE-4 (methane/LOX). Why are they not looking
at the RS-25 (LH2/LOX with similar thrust) or the Raptor engine
(methane/LOX)?

Seems like we're getting a lot of different engines when it might be
more efficient to settle on just a couple.


--
"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


space x engines are built by robotics, the engine bells are made on 3d printers
  #14  
Old May 12th 17, 02:54 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 9,552
Default RD-180 relplacement

JF Mezei wrote:

On 2017-05-11 08:56, Fred J. McCall wrote:

True. And they still have a higher power to weight ratio than any
other rocket engine, which means they still have to push those things.


If you have an existing very precise design for the SSMEs, I am trying
to understand why you can't automate with current manufactruring
technology which is by far more precise than any human operator.


I'm sure you are trying to understand that. But I don't think you
will because you don't understand how this stuff works.


I am in no way saying that producing an SSME would end up cheaper than a
Merlin. But modern automated tooling should be able to produce parts
that are well within tolerances of the SSMEs an thus make that engine
less outrageously expensive than back in the 1970s when it was first
produced.


But not as much less as you seem to think.


In terms of disposable vs re-usable, if you're keeping same design and
materials, does it make a difference when you build it whether it will
be flown a couple times (tests + 1 flight) versus re-used many many times?


They're not keeping the same materials. That's how they're making it
cheaper.


Any reduction in build quality would severely increase risk of explosion
on the one flight it does (or preceeding test firings), right?


Wrong.


I can understand how reusability comes into play when you design a new
engine from scratch since you have to choose materials and designs that
will last for dozens of hours of firing instead of maybe 30 minutes.


30 minutes is a preposterously long firing time for an expendable
engine.


But if taking an exsiting design that targetted reusability, wouldn't
newly built SSMEs be inherently re-usable even if not intended?


No, because part of the redesign changes materials.


--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson
  #15  
Old May 12th 17, 05:33 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 9,552
Default RD-180 relplacement

JF Mezei wrote:

On 2017-05-11 21:54, Fred J. McCall wrote:

They're not keeping the same materials. That's how they're making it
cheaper.


For critical parts like the turbo pump, is that wise? It means
essenstially building a new engine that will need to be tested and
validated.


They're going to have to do that anyway, since it will be a new
production line with modifications to the engine.


What materials can they substitute with which one when you consider the
very very cold and "a little hot" temperatures the engine needs to handle?

Would it be correct that for the 1970s, building the turbo pump was the
most expensive portion? Does it make sense to change materials in this
rather critical piece?


Pay me $1.16 billion and I'll work it all up for you. By the time
they get through all the modifications to manufacturing process and
materials (which won't be done for the first six engines under the
original contract) they think they can cut the price of the engine by
about a third (so just under $40 million per engine in current
dollars)



30 minutes is a preposterously long firing time for an expendable
engine.


8 minute flight and probabnly a few test firings before. Wouldn't that
bring it to 20-30 minute range?


Why would you test fire an expendable engine before you fly it? You'll
either test fire it and tear it down or you won't test fire it and
you'll fly it. They're doing test firings now because of nozzle
changes and a new engine controller and will later fly those engines,
but those engines are RS-25D reusable engines.


--
"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
  #16  
Old May 12th 17, 11:43 AM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 1,527
Default RD-180 relplacement

In article ,
says...

JF Mezei wrote:

(aka: once beyond the first 6, would additional ones become competitive
on a per pound of payload basis ? (engine only).


One would expect subsequent RS-25 engines to cost less as the 'kinks'
are worked out of the production and test processes. However, these
engines will always be more expensive than engines like BE-4 or Raptor
(or even AR1), so they're never going to compete on a price per pound
basis.


I would expect this to be the case. Liquid hydrogen being a p.i.t.a. to
handle due to its very low density and very low temperatures. I'm sure
it's a lot easier to build turbopumps for kerosene or even liquid
methane than for liquid hydrogen. The shuttle program's experience with
liquid hydrogen is that it likes to leak out of plumbing and is tricky
to get sensors to work in it (ET LH2 sensors at the bottom of the tank
caused headaches) causing launch delays.

For commercial operations focused on low cost, LH2 is a bad choice for a
lower stage. It's not a terrible choice for a high energy upper stage,
which is why ULA is sticking with it for the ACES upper stage that they
are developing.

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.
  #17  
Old May 12th 17, 12:04 PM posted to sci.space.policy
Jeff Findley[_6_]
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Posts: 1,527
Default RD-180 relplacement

In article ,
says...

Jeff Findley wrote:

In article ,
says...

I'm confused. The program to replace the RD-180 is focused on engines
with around 400,000 lb thrust at sea level. This focuses them on the
AR-1 (kerosene/LOC) and BE-4 (methane/LOX). Why are they not looking
at the RS-25 (LH2/LOX with similar thrust) or the Raptor engine
(methane/LOX)?


RS-25 is hella expensive and ULA already knows that LH2/LOX produces a
large, expensive, vehicle (e.g. Delta IV). So that's right out since
Delta IV is already flying (no development costs there). But do note
that ULA really wants to ax Delta IV in favor of Atlas V due to its high
cost.


So why aren't they using something other than RS-25 on SLS?


Because the cheaper RS-68, used on Delta IV, isn't regeneratively cooled
and can't handle the heating environment at the base of the core stage
caused by both the main engines and the SRBs. This was discovered early
on in Ares V development, which planned on using the much cheaper RS-68.

In general, Ares V/SLS is a giant cluster *&^# of a program. If it ever
does fly it will be the biggest, most expensive, lowest flight rate
launch vehicle in history.


Raptor (methane/LOX) isn't "fully baked" yet (BE-4 is ahead of it).


That sounds wrong to me. SpaceX test fired a full up Raptor engine
(albeit a lower thrust developmental engine) at their Texas facility
last year. The BE-4 has never been test fired and they didn't even
have a full engine put together until this year.


I should say it's my opinion that Raptor is behind BE-4. Since both
companies are private and somewhat secretive, good information is hard
to come by. But from what's been reported in the press, Blue Origin has
a full size complete BE-4 development engine built and is getting ready
to test fire it. SpaceX could be at that point too but all I've heard
so far is that they've fired a lower thrust development engine, which
indicates they're not quite ready for full scale testing. Blue Origin,
on the other hand, thinks BE-4 is ready for "full scale" testing.

But the proof will be on the test stand, will it not?


Seems like we're getting a lot of different engines when it might be
more efficient to settle on just a couple.


AR-1 is a "backup" engine at this point since it's so far behind BE-4 in
both schedule and (estimated) per unit price. But, AR-1 is about the
right size for two of them to be a "drop-in" replacement for RD-180 on
Atlas V. So, if ULA stumbles on Vulcan, an AR-1 engined Atlas V might
be a good stop-gap measure.


Aerojet Rocketdyne says they can start delivering AR1 engines in 2019,
so the finish line isn't all that far behind BE-4. Blue Origin says
the BE-4 will cost 60% of what an AR1 costs (at $12.5 million each);
so BE-4 engines are only around $7.5 million each? The government is
paying a lot of money to develop AR1, so I'd bet on it being pushed
for use somewhere. And AR1 does have the advantage of not needing a
bunch of new infrastructure to handle fueling and such.


ULA is more worried about the per flight cost down the road. If they
have to install liquid methane tanks and plumbing, they'll do it to
lower costs. SpaceX is already undercutting *everyone* on launch costs
and that's without taking reuse into account. ULA is desperate to stay
alive at this point with SpaceX eating into its DOD launches that it
used to have a monopoly on.


At any rate, Aerojet Rocketdyne is being paid good money to develop AR-
1. Even if it meets the same fate as J-2X, they're getting money now
which helps keep the company alive.


How many billion dollars of taxpayer money are we going to spend
developing engines that never get used? Around $1.5 billion for AR1.
Around $1.2 billion for RS-25 (which only gets used if SLS keeps
flying). Another $1.2 billion for J-2X. Meanwhile Merlin engines
used on Falcon 9 cost around $1.2 million each with engines in the
Raptor/BE-4 class going for $7.5 million each? Meanwhile the entire
development budget for New Glenn is around $2.5 billion and what
little public data there is puts development costs for Raptor engines
in the hundreds of millions of dollars (vice billions) and I expect
BE-4 development is similar. What that says is that private companies
developing engines mostly on their own nickel is looking to be an
order of magnitude cheaper than traditional contracted engine
development programs...



Maybe the US Government should get out of the game of funding
development of engines and launch vehicles. SpaceX and Blue Origin have
both proven that private industry can do this themselves, with
sufficient funding.

AJR sat on its ass for how long after RD-180 was picked for Atlas?
They've known for *decades* that the US needed a high thrust
LOX/kerosene engine to remain competitive in the global launch market
and they literally sat on their hands waiting for a government handout
to start development. AJR deserves to go under at this point. It's
management is wholly dependent on old style cost-plus contracts. They
don't know how to innovate. They don't know how to compete on cost.

NASA and DOD need to switch their space support back to the same style
of support that NACA used to give to aircraft and (jet) engine
manufacturers in the US. NACA didn't design and build commercial
engines or aircraft. And NACA certainly didn't operate its own
airlines. It's well past time for the US Government to get the hell out
of the launch business and let good old fashioned capitalism and market
based competition sort out the cheapest way to orbit.

This is the kind of **** that the "crazy" people on the old sci.space
argued for back in the early 1990s when they were pushing CATS (cheap
access to space). It's now been over 30 years since then, and SpaceX
has proven them right. The government needs to get the *&%# out of the
way and support the commercial providers rather than building yet
another Government Luanch System which will be a drain on NASA's budget
for decades to come.

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.
  #18  
Old May 12th 17, 12:07 PM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,527
Default RD-180 relplacement

In article ,
says...
The 'government program' (how we did Apollo) is the high priced
spread. It's true that it makes no sense because it has no real goal
(it changes with every President) and is too expensive to fly. The
other two efforts are commercial efforts, make more sense, spend a lot
less money, and will be far cheaper to fly.

If we did it the old way, we would ONLY have SLS, Musk and Bezos would
keep their money, and we'd get another 'flags and footprints' mission
to somewhere at best.


What kind of commercial effort for such a vehicle and program
could provide the tens of billions of dollars in private capital
to fund it? What would be the business model?


Simple. NASA should do the same thing for commercial HLV that it did
for commercial cargo and commercial crew. Both of those programs are
producing results for about 1/10th what traditional (cost plus) NASA
cost models had predicted. Yet we keep soldiering on with SLS/Orion
knowing it's costing us 10x what it should. SLS/Orion is pure pork.

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.
  #19  
Old May 12th 17, 12:15 PM posted to sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,527
Default RD-180 relplacement

In article ,
says...
Why would you test fire an expendable engine before you fly it? You'll
either test fire it and tear it down or you won't test fire it and
you'll fly it. They're doing test firings now because of nozzle
changes and a new engine controller and will later fly those engines,
but those engines are RS-25D reusable engines.


This is the "performance uber alles" mindset Henry Spencer used to
always fight against. That will never lower costs because it leads to
expendable, razor thin margin, designs that are limited in reliability.
They're limited in reliability due to the "infant mortality" problem
that every single launch is both a "test flight" and the "operational
flight". Doing double duty like that means your operational flights are
always somewhat risky in that any defect in manufacturing could doom the
flight.

The "performance uber alles" mindset is great for designing and building
ICBMs, but it's terrible if your goal is low cost, reliable, access to
space.

The real problem is that SLS is expenable and always will be.
Expendable is a stupid thing for a launch vehicle to be in the 2020s.

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.
 




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