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Towards routine, reusable space launch.



 
 
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  #31  
Old June 13th 18, 12:00 AM posted to rec.arts.sf.science,sci.astro,sci.physics,sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,714
Default Towards routine, reusable space launch.

In article , [email protected]
2017usenet1.subsume.com says...

For your reference, records indicate that
Jeff Findley wrote:

Sure, sure, Star Trek style transporters with infinite range. I'll get
right on that.


No, you won?t. But you apparently *will* use it as a straw man to avoid
actually addressing the likelihood that new technologies developed in
the future will change the economies of space launches. Hell, that?s
essentially what SpaceX is demonstrating today.


Bull****. SpaceX is not demonstrating any new technologies. They've
combined existing technologies in novel ways to solve the problems
involved in building Merlin engines and Falcon launch vehicles. There
is zero new tech in them. If you believe differently, name a new
technology they're using in their engines, launch vehicles, Dragon, and
etc.

The fact is that any other engine manufacturer, launch vehicle provider,
and spacecraft manufacturer could have done the same things. In fact,
Blue Origin *is* doing much the same with New Glenn.

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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  #32  
Old June 13th 18, 12:05 AM posted to sci.space.policy,sci.astro,sci.physics,rec.arts.sf.science
Fred J. McCall[_3_]
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Posts: 9,773
Default Towards routine, reusable space launch.

Doc O'Leary wrote on Sat, 9 Jun
2018 17:19:39 -0000 (UTC):

For your reference, records indicate that
Fred J. McCall wrote:

Doc O'Leary wrote on Fri, 8 Jun
2018 13:10:48 -0000 (UTC):

What are the actual numbers when it comes to savings from a reusable
rocket?


That depends on a lot of things.


Well, sure, but it always helps to have some data to work with before
beginning an optimization process. Best/worst cases or averages or
whatever. What the savings is related to the total cost of the launch
is going to be guiding factor on how much effort it makes sense to
expend to re-use different parts of the system.


When I say it depends on a lot of things, I meant exactly that. You
can't 'invent' data. Space Shuttle was supposedly 'partly reusable',
but it was MORE expensive than throwing away hardware with similar
capabilities. SpaceX seems to think that they can reduce the cost of
a launch by a third by reusing first stages (and that was before they
were optimized for reuse). They think that BFR/BFR Spaceship will
cost less than 1% of the hardware price per flight (a fully reusable
system good for 100 launches before servicing). Pick your poison.

It?d also be interesting to know how new technologies might
impact the economics of launching items into space (including just making
disposable launch vehicles much cheaper).


Real reuse will always be cheaper. If you can make disposable launch
vehicles much cheaper, the same technologies allow making reusable
launch vehicles much cheaper.


That is non-obvious. Ideally, I would think a “zero waste” system
would be cheapest; every kg of mass that gets sent up either stays up
(doing something useful) or was the fuel. All this booster landing
(and subsequent refurbishing for relaunch) we’re seeing, while cool,
is definitely *not* the most efficient use of resources.


Yes, magic would be more efficient, but we don't have magic.

Once you start to contemplate
the need for multiple daily launches, even recovering boosters to reuse
them seems like a slow and labor-intensive process.


But orders of magnitude faster than throwing them away and building a
new one.


But that’s still assuming old technologies rather than new ones. You
don’t “throw away” a space elevator.


You also can't build one without 'magic' because it is impossible for
materials to be strong enough.


Nor a mag-lev cannon.


Now the payload needs to be 'magic' to withstand the launch.


I’m not
sure how viable a high-altitude balloon launch would be, but it may
also be cheaper than traditional first-stage rockets.


I'm sure. It doesn't accomplish what a first stage accomplishes, so
it doesn't really matter if it's cheaper or not. What it's not is
'effective'.

On the path to a
space elevator, it seems like there should be many more ways to reach
escape velocity that do a better job than what Musk is doing today.


You've discovered a good supply of unobtainium, have you? Otherwise,
rockets are your man for getting stuff to orbit for the foreseeable
future.


It’s always a good idea to noodle around with other technologies, no
matter how impossible they appear to be today.


Building a tether on Earth requires materials that are stronger than
materials can theoretically be. Noodle all you like. Basic laws of
physics aren't going to change no matter how hard you wish.


Because, yes, rockets
are the way to get to orbit, but I’m most interested in the
*unforeseeable* future that has humans on other planets around other
stars. Just being satisfied with rockets is not going to make that
happen.


When you're in entirely the wrong newsgroup. You need something that
starts with 'alt' or 'rec'.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
  #33  
Old June 13th 18, 01:08 AM posted to rec.arts.sf.science,sci.astro,sci.physics,sci.space.policy
Alain Fournier[_3_]
external usenet poster
 
Posts: 354
Default Towards routine, reusable space launch.

On Jun/12/2018 at 5:36 PM, Fred J. McCall wrote :
Doc O'Leary wrote on Tue, 12 Jun
2018 15:00:13 -0000 (UTC):

For your reference, records indicate that
Fred J. McCall wrote:

Doc O'Leary wrote on Mon, 11 Jun
2018 22:35:20 -0000 (UTC):

Chicken and egg. The fact is that we *do* sometimes have to
elaborately engineer spacecraft in order to make them small enough to
fit into a nose cone or payload bay of a rocket.


Head and ass. Cite for such payloads? Be specific. You're posting
into a 'sci' newsgroup. Handwavium is not sufficient.


Then I must say I note a lack of citations for your own claims.


I haven't made any claims.


Mine
are easy enough to demonstrate. I can literally link to just about
*any* payload that unfolds to deploy as evidence. Let’s start with
the obvious:

https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#/media/File:JWST_launch_configuration.png


Not a good example. Things like solar arrays are launched folded
because they can't take acceleration without snapping off, not because
they're 'too bulky'. Try again?


The telescope is folded, not only the solar arrays.


Alain Fournier
  #34  
Old June 13th 18, 06:12 AM posted to rec.arts.sf.science,sci.astro,sci.physics,sci.space.policy
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,773
Default Towards routine, reusable space launch.

Alain Fournier wrote on Tue, 12 Jun 2018
20:08:10 -0400:

On Jun/12/2018 at 5:36 PM, Fred J. McCall wrote :
Doc O'Leary wrote on Tue, 12 Jun
2018 15:00:13 -0000 (UTC):

For your reference, records indicate that
Fred J. McCall wrote:

Doc O'Leary wrote on Mon, 11 Jun
2018 22:35:20 -0000 (UTC):

Chicken and egg. The fact is that we *do* sometimes have to
elaborately engineer spacecraft in order to make them small enough to
fit into a nose cone or payload bay of a rocket.


Head and ass. Cite for such payloads? Be specific. You're posting
into a 'sci' newsgroup. Handwavium is not sufficient.

Then I must say I note a lack of citations for your own claims.


I haven't made any claims.


Mine
are easy enough to demonstrate. I can literally link to just about
*any* payload that unfolds to deploy as evidence. Let’s start with
the obvious:

https://en.wikipedia.org/wiki/James_Webb_Space_Telescope#/media/File:JWST_launch_configuration.png


Not a good example. Things like solar arrays are launched folded
because they can't take acceleration without snapping off, not because
they're 'too bulky'. Try again?


The telescope is folded, not only the solar arrays.


And THAT is because you cannot make a single mirror that large to
adequate precision, so once it's in pieces you might as well fold the
sucker up.


--
"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
  #35  
Old June 13th 18, 09:27 AM posted to rec.arts.sf.science,sci.astro,sci.physics,sci.space.policy
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,773
Default Towards routine, reusable space launch.

JF Mezei wrote on Wed, 13 Jun 2018
02:15:38 -0400:

On 2018-06-12 19:00, Jeff Findley wrote:

Bull****. SpaceX is not demonstrating any new technologies.


Is friction fit welding for the tanks a first for rockets?

I know it isn't "new" since it was used by Airbus and others, but
wondering if it was first use in rockets/tanks.


I suspect it was used for wheels on rail cars and other similar things
long before it was used on aircraft (and frankly it seems a poor fit
for aircraft use).


Since SpaceX is developping composite tanks for BFR, was there any
though of puttting composite tanks for Block 5 Falcon 9? Just
wondering if there would be a big payback in weight or if the difference
not worth the trouble of developping/testing/certifying such a tank.


I doubt it. They were more interested in fixing the existing COPV
design than grounding waiting for a whole new technology.


--
"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
  #37  
Old June 13th 18, 11:46 AM posted to rec.arts.sf.science,sci.astro,sci.physics,sci.space.policy
Jeff Findley[_6_]
external usenet poster
 
Posts: 1,714
Default Towards routine, reusable space launch.

In article ,
says...

On 2018-06-12 19:00, Jeff Findley wrote:

Bull****. SpaceX is not demonstrating any new technologies.


Is friction fit welding for the tanks a first for rockets?

I know it isn't "new" since it was used by Airbus and others, but
wondering if it was first use in rockets/tanks.


Doesn't matter if it's a "first for rockets", it's been done before in
other industries (aerospace at that). So, it's absolutely existing
tech. Again, SpaceX hasn't invented any new technologies here.

Since SpaceX is developping composite tanks for BFR, was there any
though of puttting composite tanks for Block 5 Falcon 9? Just
wondering if there would be a big payback in weight or if the difference
not worth the trouble of developping/testing/certifying such a tank.


Composite structures/tanks are also not new. Composites are heavily
used in aerospace. For space specifically, the X-33 program designed
and built cryogenic composite tanks. They failed during testing more
due to their complex geometry than anything else. So no new tech there.

BFR/BFS avoids the complex geometry problem and goes back to a more
"delta clipper" sort of design. Also not new, at least in concept.

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.
  #38  
Old June 13th 18, 01:57 PM posted to sci.space.policy,sci.physics,sci.astro,rec.arts.sf.science
Doc O'Leary[_3_]
external usenet poster
 
Posts: 13
Default Towards routine, reusable space launch.

For your reference, records indicate that
Jeff Findley wrote:

In article , [email protected]
2017usenet1.subsume.com says...

For your reference, records indicate that
Jeff Findley wrote:

Sure, sure, Star Trek style transporters with infinite range. I'll get
right on that.


No, you won?t. But you apparently *will* use it as a straw man to avoid
actually addressing the likelihood that new technologies developed in
the future will change the economies of space launches. Hell, that?s
essentially what SpaceX is demonstrating today.


Bull****. SpaceX is not demonstrating any new technologies. They've
combined existing technologies in novel ways to solve the problems
involved in building Merlin engines and Falcon launch vehicles. There
is zero new tech in them. If you believe differently, name a new
technology they're using in their engines, launch vehicles, Dragon, and
etc.


Sigh Of *course* there’s no “new technology” in *anything* that’s
in the world today. Your engineering mindset has you in a motivated
reasoning spiral. The fact remains that, over the course of time,
new technologies have been developed that have made their way into
space programs. SpaceX is taking advantage of some of those
technologies today. It is a safe bet that such innovations will occur
in the future, and somebody will take advantage of them.


--
"Also . . . I can kill you with my brain."
River Tam, Trash, Firefly


  #39  
Old June 13th 18, 10:35 PM posted to sci.space.policy,sci.physics,sci.astro,rec.arts.sf.science
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,773
Default Towards routine, reusable space launch.

Doc O'Leary wrote on Wed, 13 Jun
2018 12:57:19 -0000 (UTC):

For your reference, records indicate that
Jeff Findley wrote:

In article , [email protected]
2017usenet1.subsume.com says...

For your reference, records indicate that
Jeff Findley wrote:

Sure, sure, Star Trek style transporters with infinite range. I'll get
right on that.

No, you won?t. But you apparently *will* use it as a straw man to avoid
actually addressing the likelihood that new technologies developed in
the future will change the economies of space launches. Hell, that?s
essentially what SpaceX is demonstrating today.


Bull****. SpaceX is not demonstrating any new technologies. They've
combined existing technologies in novel ways to solve the problems
involved in building Merlin engines and Falcon launch vehicles. There
is zero new tech in them. If you believe differently, name a new
technology they're using in their engines, launch vehicles, Dragon, and
etc.


Sigh Of *course* there’s no “new technology” in *anything* that’s
in the world today. Your engineering mindset has you in a motivated
reasoning spiral. The fact remains that, over the course of time,
new technologies have been developed that have made their way into
space programs. SpaceX is taking advantage of some of those
technologies today. It is a safe bet that such innovations will occur
in the future, and somebody will take advantage of them.


And it's an even safer bet that none of those 'new technologies' are
going to replace "throwing stuff aft to move forward". A space
elevator on Earth requires not 'new technology', but 'new physics'.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
  #40  
Old June 13th 18, 10:36 PM posted to sci.space.policy,sci.astro,sci.physics
Fred J. McCall[_3_]
external usenet poster
 
Posts: 9,773
Default Towards routine, reusable space launch.

Jeff Findley wrote on Wed, 13 Jun 2018
06:41:27 -0400:

In article ,
says...

Because, yes, rockets
are the way to get to orbit, but I?m most interested in the
*unforeseeable* future that has humans on other planets around other
stars. Just being satisfied with rockets is not going to make that
happen.


When you're in entirely the wrong newsgroup. You need something that
starts with 'alt' or 'rec'.


Unfortunately, rec.arts.sf.science is in the stupid distribution list of
the posts in this thread. I've removed it from this reply.


I know where the git is posting from. I'm trying to make the point
that he shouldn't be posting HERE.


--
You are
What you do
When it counts.
 




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