Author Topic: Possible uses for the expended Jupiter 120 core stage in orbit.  (Read 17137 times)

Offline tankmodeler

  • Regular
  • Full Member
  • ****
  • Posts: 643
  • Brampton, ON, Canada
  • Liked: 8
  • Likes Given: 0
Even if you can't use it in orbit, I know scrap haulers in the outback who would be more than happy to get their hands on a few tons of expensive alloys.  It seems a waste that large satellites are always deorbited into the ocean, where everything sinks.
The problem with this, of course, is that you don't get it back in a relatively nice package. Something like a tank would shred itself into little bits on re-entry and only a few very large and solid components would actually hit the ground in a relatively contained area. This disregards the large proportion of the tank that would be vapourised upon re-entry. And, by "relatively contained area" I mean something like the size of Queensland. Having an engine land in the middle of Brisbane or even Noosa Heads is not what any government is going to permit. Uncontrolled re-entries are really pretty uncontrolled.

Plus, by the time it's survived a re-entry, the temperatures have generally played merry hell with the material properties, so the scrap value really wouldn't be that high anyway.

Having a robust enough orbital economy so that we can re-use the materials in orbit is what we should all be aiming for, notwithstanding that it's 100+ years in the future.

Paul
Sr. Mech. Engineer
MDA

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6
It really is a shame that we are in such preliminary stages of space travel that we don't have some kind of machine shop in orbit.  I just think about how much more practical it could be (in many, but not all, cases) to fabricate what we need in orbit rather than have to have something made on earth and sent up to orbit for however many hundreds of dollars per pound, let alone being able to make rapid repairs in emergency situations.  Also, this would be very good experience for a trip to Mars where spare parts would be months (at least) away.
  This is just one item that needs to go on the list of infrastructure in space along with a space tug to safely transport payload around in orbit.

Drew 
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21451
  • Likes Given: 428
1.   I just think about how much more practical it could be (in many, but not all, cases) to fabricate what we need in orbit rather than have to have something made on earth and sent up to orbit for however many hundreds of dollars per pound,

2.  let alone being able to make rapid repairs in emergency situations. 


1.  no, for the flight rates now days, it is still cheaper to do it on the ground.   Just as Spacex doesn't built the falcon on Kwaj

2.  For what missions?  Other than ISS, none.

Offline Archibald

  • Senior Member
  • *****
  • Posts: 2611
  • Liked: 500
  • Likes Given: 1096
One Important thing to remember was that Skylab was much smaller in diameter than the Shuttle Tank, yet had a massive internal volume.  Why not just convert a J-232 Upperstage into a lab module, ala Skylab/S-IVB, it still would be a massive station.
Why not use just a converted H2 tank from a J120 core stage no foam etc and pre outfitted with airlocks,MMOD shielding and a basic RCS and have a truly huge station module.
I say module as the days of single module stations was over since the 70s and all future stations have been multiple module affairs.
Even the giant BA330 is just a part of a larger space station.

It also should be noted we have much cheaper cargo options now then the Apollo CSM and Saturn IB of the 60s so a finding in the 60s is likely no longer valid.


In my mind the idea wasn't to send up a huge module as a single station, but many, although significantly less than ISS, sent up to build a large multi-purpose station.  I envisioned sending up a standardised module with a six-point docking module attached.  Every subsequent module would have this same configuration and a space station could be assembled Tinkertoy style.

Something like Mir base blocks (DOS-7 and DOS-8) ?
http://en.wikipedia.org/wiki/Image:Mir_base_block_drawing.png

Maybe an enlarged variant, up to 8.4m (Shuttle E.T) or 10m diameter?

According to Astronautix
http://www.astronautix.com/craft/spaation.htm

The 1969 Space-Station core module was primarily designed for a zero-G environment. It was 10 m in diameter, 16.5 m long, and had five deck levels with a total volume of 930 cubic meters (Mass 88 tons)


Han shot first and Gwynne Shotwell !

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6
1.   I just think about how much more practical it could be (in many, but not all, cases) to fabricate what we need in orbit rather than have to have something made on earth and sent up to orbit for however many hundreds of dollars per pound,

2.  let alone being able to make rapid repairs in emergency situations. 


1.  no, for the flight rates now days, it is still cheaper to do it on the ground.   Just as Spacex doesn't built the falcon on Kwaj

2.  For what missions?  Other than ISS, none.

That's what I meant by PRELIMINARY STAGES of space travel.  RIGHT NOW it is not practical to try and process materials in orbit, but if we had some kind of ability to process materials in orbit, then we could use the expended core stages that we are talking about in this thread for the raw materials. 
  Eventually, not in the near future but eventually, the technology and the need to process materials in orbit will present itself.  Having a processing infrastructure in place as well as already having raw materials in the form of these core stages already in orbit will enable us to work on future projects much easier and quicker.       
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
The problem is that the foam on the outside of the tanks degrades fast in space.   It breaks off and becomes a high-velocity debris field miles in diameter.   If that orbit then intersects with any other satellite or spacecraft the results of particulate foam traveling at a potential collision speed of up to 35,000mph would be nothing short of fatal.

There is not currently any safe way to store these stages (or *any* foam-covered stages for that matter) in orbit for the years, maybe decades, until we develop that sort of manufacturing capability in LEO.

Once we have the manufacturing capability we can probably find ways to gather all the stages from that point onwards, but we are -- sadly -- a long way off still.


The principle is great.   But the practical realities make it extremely difficult.

Ross.
« Last Edit: 10/23/2008 02:38 pm by kraisee »
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
Following-up on my own message...

I am all for building the capabilities to perform manufacturing on-orbit at the earliest possible opportunity.

But those will require serious $$$ investment and heavy-lift capabilities.


My concern *right now* is that Ares is sucking up all the $$$ in the room and that the 2-vehicle plan is never going to be finished, leaving us without any heavy lift capabilities at all.   That will kill the manufacturing plan from two different directions.

So my #1 concern *today* is to make sure that doesn't happen.   If we don't bypass Ares, the manufacturing facilities we both want will a) never be affordable, and b) will not be able to be launched anyway.


The Jupiter launchers are *not* the goal (as Ares seems to be the goal for Griffin).   The Jupiter's are just a low-cost, relatively straight-forward *TOOL* which enables us to pursue many different goals by not choking the budget, and by providing all the lift capabilities we need -- though not necessarily the ones which are just 'cool'.

I just wanted to point that perspective out, just in case it was getting lost.

It is the high costs for the two Ares launchers which is going to spell doom to this idea (and many, many others) far more effectively than any technical hitches ever will.   We simply won't ever be able to afford to do anything like this.

Ross.
« Last Edit: 10/23/2008 02:50 pm by kraisee »
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6
Granted, the present core design would pose problems primarily because of the foam issue, and the idea of some kind of processing plant in orbit is a long way off, so for the immediate future the concept of using core stages in orbit is impractical. 
   I guess I was considering a strategy for the future, where we would be doing processing and construction in orbit.  A new core stage could be designed with orbital construction in mind.  Maybe a different, more robust foam, or some other form of insulation altogether.  Either way it is one possible course of action to take in the future.  Granted these ideas are somewhat whimsical, but I'm sure they said the same thing about Tsiolkovsky's ideas a hundred years ago!

Drew
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
Personally I think this capability will only exist after we have already established large-scale ISRU facilities on at least one or more NEO's and on the Lunar surface.

A day will come, eventually, when processing materials in LEO becomes economically viable and even desirable.   That's the time when re-processing of spent stages will become a truly useful "side-effect" option.

What I'm saying is that I believe that recycling stages is going to come only *after* we already have systems in place to do other processing work.

But we are going to have to create all that infrastructure first.   And creating the initial infrastructure, the one which will allow that even larger infrastructure to be built, is my current target :)

Ross.
« Last Edit: 10/23/2008 04:56 pm by kraisee »
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21451
  • Likes Given: 428
I guess I was considering a strategy for the future, where we would be doing processing and construction in orbit.  A new core stage could be designed with orbital construction in mind. 

By that time, there will be RLV's and no expendable cores to use

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6
I guess I was considering a strategy for the future, where we would be doing processing and construction in orbit.  A new core stage could be designed with orbital construction in mind. 

By that time, there will be RLV's and no expendable cores to use

Let's hope so!  LOL 
Along those lines, I wonder if there is a way of making a reuseable command module along the lines of Orion but with an expendable/replaceable heatshield.  THAT might cut costs significantly. 
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
That was the idea when Orion was landing on land.   But dunking it in the Ocean every time is not at all helpful WRT re-use.   Baselining sea landings has made that option far less likely.

Jupiter's considerable extra performance would allow land-landings to be put back though.

Ross.
« Last Edit: 10/23/2008 05:18 pm by kraisee »
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline luke strawwalker

  • Regular
  • Full Member
  • ****
  • Posts: 1032
  • Liked: 9
  • Likes Given: 0
ET was better since it was just a tank, no engines, avionics, etc
{snip}

Avionics and engines are the expensive bits.  Could the J-120 core be refuelled and used as an Earth Departure Stage?

RS-68 isn't restartable

Crazy thought here but I'm outside the box... can't even see it from here...

What if you put a restartable J-2 in between the RS-68's and only ignited it on orbit.  I wouldn't see any purpose in igniting it on the ground, as overexpansion would cause problems, as well as fuel consumption from the core and probably result in over-acceleration anyway.  The problem with using a core for an EDS though is the lousy mass fraction carrying the dead weight of the RS-68's and thrust structure through TLI or TMI, which really kills you, and the size of the core is way overkill for what you'd be sending out anyway, most likely, especially with a single J-2 mounted in the middle.  Maybe if the engines/thrust structure were 'stage and a half' type design to get rid of most of the dead weight you might have something, but that creates a whole other set of costs/problems.  Also I'm thinking the construction of the core would be seriously overkill for an EDS type stage.  Fuelling it would require a second launch of either another similar size vehicle or multiple smaller vehicles, in which case you're probably better off launching a dedicated more optimized EDS anyway.... 

Just thinking off the cuff but I see more problems with this idea than solutions... Oh well, back to the drawing board... LOL:)  OL JR :)
NO plan IS the plan...

"His plan had no goals, no timeline, and no budgetary guidelines. Just maybe's, pretty speeches, and smokescreens."

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6

Crazy thought here but I'm outside the box... can't even see it from here...

What if you put a restartable J-2 in between the RS-68's and only ignited it on orbit.  I wouldn't see any purpose in igniting it on the ground, as overexpansion would cause problems, as well as fuel consumption from the core and probably result in over-acceleration anyway.  The problem with using a core for an EDS though is the lousy mass fraction carrying the dead weight of the RS-68's and thrust structure through TLI or TMI, which really kills you, and the size of the core is way overkill for what you'd be sending out anyway, most likely, especially with a single J-2 mounted in the middle.  Maybe if the engines/thrust structure were 'stage and a half' type design to get rid of most of the dead weight you might have something, but that creates a whole other set of costs/problems.  Also I'm thinking the construction of the core would be seriously overkill for an EDS type stage.  Fuelling it would require a second launch of either another similar size vehicle or multiple smaller vehicles, in which case you're probably better off launching a dedicated more optimized EDS anyway.... 

Just thinking off the cuff but I see more problems with this idea than solutions... Oh well, back to the drawing board... LOL:)  OL JR :)
   Well, let's not go back the drawing board completely!  You wouldn't necessarily have to get rid of the dead weight.  It would be nice, but not compulsory and the hardware necessary to jettison this weight would add to the complexity as well as the weight of the vehicle.  It may not be a great idea for sending a crew into TLI or TMI, but for sending cargo on ahead of the mission or resupply missions this might have some merit.

Drew
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline tankmodeler

  • Regular
  • Full Member
  • ****
  • Posts: 643
  • Brampton, ON, Canada
  • Liked: 8
  • Likes Given: 0
   Well, let's not go back the drawing board completely!  You wouldn't necessarily have to get rid of the dead weight.  It would be nice, but not compulsory and the hardware necessary to jettison this weight would add to the complexity as well as the weight of the vehicle.  It may not be a great idea for sending a crew into TLI or TMI, but for sending cargo on ahead of the mission or resupply missions this might have some merit.

Drew
Dragging that much excess mass to the moon for any reason makes for an untennable design, even for cargo. The cost greatly outweighs any percieved benefit; if it would actually work at all.

Paul
Sr. Mech. Engineer
MDA

Offline davamanra

  • Full Member
  • **
  • Posts: 261
  • Liked: 26
  • Likes Given: 6
   Well, let's not go back the drawing board completely!  You wouldn't necessarily have to get rid of the dead weight.  It would be nice, but not compulsory and the hardware necessary to jettison this weight would add to the complexity as well as the weight of the vehicle.  It may not be a great idea for sending a crew into TLI or TMI, but for sending cargo on ahead of the mission or resupply missions this might have some merit.

Drew
Dragging that much excess mass to the moon for any reason makes for an untennable design, even for cargo. The cost greatly outweighs any percieved benefit; if it would actually work at all.

Paul

Well, it's just one possible use for the core.  Since it would already be in orbit, it would be a way to deliver cargo instead of having to launch a special mission all the way from Earth's surface.  Now THAT cost would outweigh any benefit. 
Better to have more than you want than less than you need.
All's fair in love, war and engineering.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21451
  • Likes Given: 428
Well, it's just one possible use for the core.  Since it would already be in orbit, it would be a way to deliver cargo instead of having to launch a special mission all the way from Earth's surface.  Now THAT cost would outweigh any benefit. 

The core doesn't reach orbit for missions with an upperstage.  It doesn't even make to Africa.  Only on the Orion missions does it reach orbit.

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1