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SpaceX has plans--BIG plans



 
 
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  #31  
Old August 4th 10, 09:21 PM posted to sci.space.policy,sci.space.history
Rick Jones[_3_]
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Posts: 587
Default SpaceX has plans--BIG plans


There may have been engineering challenges in the '50's, but
technology and construction techniques have improved significantly
since then.


It's the unknown unknowns that get you. Materials and construction
techniques aren't the problem. Things like injector designs don't
necessarily scale up easily when you consider problems like
combustion instability.


Even if things look like they're going smoothly, you still want to
have a robust, somewhat lengthy, ground test period to make sure
you're not missing something. This takes time and money even if you
don't run into significant problems.


You mean the computer simulation isn't accurate? Inconceivable!

rick jones
--
The glass is neither half-empty nor half-full. The glass has a leak.
The real question is "Can it be patched?"
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
  #32  
Old August 4th 10, 09:33 PM posted to sci.space.policy,sci.space.history
Jeff Findley
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Posts: 5,012
Default SpaceX has plans--BIG plans

In article WbqdnQFgxsteG8XRnZ2dnUVZ_r-
hdakotatelephone, says...

That may be the problem; Lox/kerosene engine designs don't scale up
well, as the Soviets found out with their failed RD-105 engine design;
which was based on scaling up the V-2 Lox/alcohol engine technology:
http://www.astronautix.com/engines/rd105.htm
A photo of it he
http://www.b14643.de/Spacerockets_1/...nes/RD-105.jpg
When the very long combustion chamber shows up, it's a sure sign
something isn't working right in the combustion process.
Glushko foolishly promised Stalin that it would be easy and quick to
develop, and got into real hot water when it flopped.


From the discussions I've read of rocket engine development, this isn't
unique to LOX/kerosene engines. Scaling things up may seem easy, but
things like combustion instability can still cause trouble.

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?
  #35  
Old August 5th 10, 02:18 AM posted to sci.space.policy,sci.space.history
Matt Wiser
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Posts: 575
Default SpaceX has plans--BIG plans

On Aug 3, 5:15*pm, Pat Flannery wrote:
On 8/3/2010 7:36 AM, Jeff Findley wrote:



I wish them luck, but they'll have challenges. *The F-1 development
program was filled with engineering challenges, despite the fact that in
many ways it was just a scaled up version of previous LOX/kerosene
engines.


That may be the problem; Lox/kerosene engine designs don't scale up
well, as the Soviets found out with their failed RD-105 engine design;
which was based on scaling up the V-2 Lox/alcohol engine technology:http://www.astronautix.com/engines/rd105.htm
A photo of it hehttp://www.b14643.de/Spacerockets_1/...nes/RD-105.jpg
When the very long combustion chamber shows up, it's a sure sign
something isn't working right in the combustion process.
Glushko foolishly promised Stalin that it would be easy and quick to
develop, and got into real hot water when it flopped.

Pat


Did Glushko live to retell the experience? Stalin was usually
uncompromising when it came to punishment of those who failed to
deliver for him. Mayaschev was lucky that Stalin was dead when the M-4
Bison bomber came out: it clearly lacked the range for a round-trip
bombing mission to the U.S., and when he told Khrushchev that the
plane could hit the U.S. and land in Mexico, Nikita Sergeyich is
supposed to have roard back "What do you think Mexico is, our mother-
in-law? Even if the plane landed there, they wouldn't give it back!"
If Mayaschev had to tell Stalin the same thing, those would be the
last words he ever said.....because a 9-mm brain hemmorage would
follow shortly thereafter.
  #36  
Old August 5th 10, 02:30 AM posted to sci.space.policy,sci.space.history
Alan Erskine[_3_]
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Posts: 1,026
Default SpaceX has plans--BIG plans

On 5/08/2010 6:37 AM, Jeff Findley wrote:


Liquid rocket engine development isn't necessarily as quick and easy as
some would think.

Jeff


Seems to be going well for SpaceX. ;-)

Two engines; rapid development and only a couple of minor (albeit costly
- two prototype vehicles lost) problems in the Falcon 1, but that's been
sorted out.

The thing that impresses me is the small scale of the operation compared
to the scale of achievement.
  #37  
Old August 5th 10, 12:02 PM posted to sci.space.policy,sci.space.history
Pat Flannery
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Posts: 18,465
Default SpaceX has plans--BIG plans

On 8/4/2010 5:18 PM, Matt Wiser wrote:
On Aug 3, 5:15 pm, Pat wrote:
On 8/3/2010 7:36 AM, Jeff Findley wrote:



I wish them luck, but they'll have challenges. The F-1 development
program was filled with engineering challenges, despite the fact that in
many ways it was just a scaled up version of previous LOX/kerosene
engines.


That may be the problem; Lox/kerosene engine designs don't scale up
well, as the Soviets found out with their failed RD-105 engine design;
which was based on scaling up the V-2 Lox/alcohol engine technology:http://www.astronautix.com/engines/rd105.htm
A photo of it hehttp://www.b14643.de/Spacerockets_1/...nes/RD-105.jpg
When the very long combustion chamber shows up, it's a sure sign
something isn't working right in the combustion process.
Glushko foolishly promised Stalin that it would be easy and quick to
develop, and got into real hot water when it flopped.

Pat


Did Glushko live to retell the experience? Stalin was usually
uncompromising when it came to punishment of those who failed to
deliver for him.


Yeah, Glushko lived...he was one of the few people that knew how to make
rocket engines, so was too important to have liquidated.

Mayaschev was lucky that Stalin was dead when the M-4
Bison bomber came out: it clearly lacked the range for a round-trip
bombing mission to the U.S., and when he told Khrushchev that the
plane could hit the U.S. and land in Mexico, Nikita Sergeyich is
supposed to have roard back "What do you think Mexico is, our mother-
in-law? Even if the plane landed there, they wouldn't give it back!"
If Mayaschev had to tell Stalin the same thing, those would be the
last words he ever said.....because a 9-mm brain hemmorage would
follow shortly thereafter.


If you think about it, once WWIII broke out, there probably wouldn't be
a USSR to return to anyway; at least not the base it came from.
The same would apply to our B-52s.
Khrushchev used the M-4 Bison's short range and Tu-20 Bear's
vulnerability due to its lower speed as a rational to curtail the Soviet
strategic bomber program and save defense spending by basing the Soviet
deterrent force on a "Biad" of ICBM's and SLBM's, rather than a "triad"
like the US had.
Even then, he canceled the ICBM version of the Proton rocket, saying "I
can build the giant silos for these or socialism; but not both at once".
The ICBM version of the N-1 was really something to behold:
http://www.astronautix.com/graphics/n/n11gr2.jpg
It was based on the second and third stages of the standard N-1.
Two or three of these would theoretically be able to destroy all major
US cities with huge yield warheads sent in on a depressed trajectory to
help avoid ABM's, or into low orbit from which they would descend onto
their targets when commanded, allowing an attack from the south to avoid
radar detection rather than going over the North Pole like conventional
ICBM's.

Pat
  #38  
Old August 5th 10, 12:08 PM posted to sci.space.policy,sci.space.history
Jeff Findley
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Posts: 5,012
Default SpaceX has plans--BIG plans

In article m,
says...

On 5/08/2010 6:37 AM, Jeff Findley wrote:


Liquid rocket engine development isn't necessarily as quick and easy as
some would think.

Jeff


Seems to be going well for SpaceX. ;-)

Two engines; rapid development and only a couple of minor (albeit costly
- two prototype vehicles lost) problems in the Falcon 1, but that's been
sorted out.

The thing that impresses me is the small scale of the operation compared
to the scale of achievement.


I don't think that the actual engine development program at SpaceX was
completely smooth. They certainly have some good engineers, but they
were still starting essentially from scratch. They deliberately chose a
gas generator cycle for their LOX/kerosene Merlin 1 engines (surely
partly to control development and operational costs). This was a
conservative approach that didn't necessarily push the state of the art
in liquid rocket engine development forward, at least in terms of
technology.

Despite that conservative approach, a quick search of news articles
indicates that there was at least one engine failure on the test stand
(combustion chamber #13) despite the fact that all of the previous
combustion chambers "worked fine".

Scaling this up to a Merlin 2 engine which is in the F-1 engine class
(in terms of thrust) may be difficult, depending on what problems crop
up. And as Merlin 1 development showed, failures may not crop up at the
beginning of the engine test program. Funding an engine test program
for an engine as big as Merlin 2 will almost certainly cost more than
Merlin 1 simply due to the large scale up in size (thrust).

Jeff
--
The only decision you'll have to make is
Who goes in after the snake in the morning?
  #39  
Old August 5th 10, 07:16 PM posted to sci.space.policy
kT
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Posts: 5,032
Default SpaceX has plans--BIG plans

On 8/2/2010 9:24 AM, Anonymous wrote:
"Damon wrote in message
...
Too much detail to go into here, follow the links:

http://commercialspace.pbworks.com/f...M%20small.pptx

http://commercialspace.pbworks.com/f...20Propulsion%2
0small.pptx



Discusses Raptor upper stage and engine, Merlin 2 engine, Falcon X and
Falcon XX, which is a tad larger and more powerful than the Saturn V,
and technology for manned deep space exploration.


Wow, this all sounds terribly exciting, but none of it is official.
What's SpaceX's response to all this?

The Ares X and Ares XX sound ambitious, on par with the Saturn V in
payload and performance. I assume these are SpaceX's proposals for
NASA's Heavy Lift program which Congress has ordered. It will be
interesting to see how this will stack up against Boeing's Ares V-
derivative, both in cost and development time. Boeing has done next to
nothing on Ares V, so in terms of development time they should both
stack up pretty evenly.

It would be strategically unwise for the U.S. government to put all its
eggs (COTS and Heavy Lift) in one basket (i.e. in the hands of one
company), so I doubt SpaceX will be allowed to develop Ares XX, but it
depends on the price-tag they put on it. If they quote something on the
order of $2 billion to $3 billion it will be difficult for the
government to resist (Boeing has quoted something like $ 15 billion for
Ares-V IIRC). OTOH from the drawings it looks like they're already
commited to developing the larger Merlin-2 engine, vital for even
attempting to consider something like Ares XX.

Good luck SpaceX!


If anybody is really interested in these kinds of unaffordable and
unsustainable monster zombie vampire Jesus rockets, I am blobbing them
again on my new and improved stock Wordpress blog at the same old URL :

http://cosmic.lifeform.org

Satire. Parody. Call it what you will. And no AJAX development either!

As always, you can peruse my papers on these and other subjects,
privately, without IP monitoring or tracking, at my ISP repository :

http://webpages.charter.net/tsiolkovsky/

Enjoy your anonymous rocket browsing!
  #40  
Old August 5th 10, 09:10 PM posted to sci.space.policy,sci.space.history
Pat Flannery
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Posts: 18,465
Default SpaceX has plans--BIG plans

On 8/5/2010 3:08 AM, Jeff Findley wrote:

I don't think that the actual engine development program at SpaceX was
completely smooth. They certainly have some good engineers, but they
were still starting essentially from scratch. They deliberately chose a
gas generator cycle for their LOX/kerosene Merlin 1 engines (surely
partly to control development and operational costs). This was a
conservative approach that didn't necessarily push the state of the art
in liquid rocket engine development forward, at least in terms of
technology.

Despite that conservative approach, a quick search of news articles
indicates that there was at least one engine failure on the test stand
(combustion chamber #13) despite the fact that all of the previous
combustion chambers "worked fine".


The one that failed tried a radical idea out to cut engine costs; it
used a ablative liner on the interior wall of the combustion chamber
rather than regenerative cooling. The idea was that this would simplify
the engine and lower its production costs, and after booster recovery
the combustion chamber would be opened and a new liner inserted before
the next flight.
Many rocket engine engineers were skeptical of the concept, and it
turned out they were correct. During a firing test the liner
disintegrated and was blown out of the engine nozzle.
SpaceX ditched the concept and went back to the tried and true
regenerative combustion chamber cooling concept.
SpaceX's triumph may have been _not_ to use any revolutionary technology
(other than the parachute recovery of the first stage that has yet to be
proven), like so many failed private rocket companies tried (and Roton
comes especially to mind in that regard) but rather just stick to tried
and true technology and figure a way to cut the cost.

Pat
 




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