Ground-LEO Cargo Transfer?

[PriestLizard]

Hi there.

I'm thinking about doing a series of missions where I want to simulate the construction and deployment of a lunar base. However, I came across a problem which really frustrates me - as it probably also frustrates the mission designers from NASA : how can I transport cargo from earth to LEO and vice versa?

I'm talking about rather "realistic" solutions here. No XR5, no Shuttle-A. Shuttle-A is a nice vessel and I planned to use it for LEO/lunar cargo transfer, but its probably unrealistic that the Shuttle-A would ever ascent from the ground... and its unthinkable that it would perform a reentry.

For my personal standards of "realism" the combination of Energia launcher plus DGIV (with Mk1 engine) is good enough. Its impossible to transfer big amounts of cargo though. I could simulate the construction of a Shuttle-A in LEO by launching several DGIVs untill the total cargo mass matches the mass of a Shuttle-A... but this would only solve the LEO/lunar transfer.

Any ideas? Maybe unmanned crafts like Soyuz? Are they easy to use? I'm not a pro when it comes to scenario editing. I'm also not talking about specific payloads here... I just need a craft which transports neutral "cargo" from earth to LEO and back.

Is the space shuttle really the only option here? Its payload capability is rather OK and it could transport cargo back to earth - which is nice. (Lunar ressources ). But since both DGIV and Shuttle-A are like 2030+ technology - it seems unlogical to still use the space shuttle at this time.

I know this is a tough problem from a realistic point of view and maybe the biggest restriction to space travel right now... but I wonder if some modders have found a rather good solution for the time ~2030?

Thanks in advance.
Bye PriestLizard

 

[Jarvitä]

How about Energia+Buran-T?

 

[PriestLizard]

How about Energia+Buran-T?

Yes I already thought about that. But this combination could only LAUNCH cargo to LEO. It couldn't return cargo from a space station to the ground. Or could it? I dont think its possible.

 

[Andy44]

Is the space shuttle really the only option here?

For realistic 2-way systems, yes.

No one has, to my knowledge, created a speculative add-on which can carry more freight than the shuttle both up and down without fake engines. The entire DG series is all sci fi.

I have wanted to built a realistic shuttle replacement addon for some time, but I don't have the time or the skillz right now.

ETA: Buran can return cargo, as well. It's a space shuttle, after all.

 

[PriestLizard]

For realistic 2-way systems, yes.

No one has, to my knowledge, created a speculative add-on which can carry more freight than the shuttle both up and down without fake engines. The entire DG series is all sci fi.

I have wanted to built a realistic shuttle replacement addon for some time, but I don't have the time or the skillz right now.

ETA: Buran can return cargo, as well. It's a space shuttle, after all.

Hmmmm. Basically I really like the Shuttle-A ... maybe I will just forget about the fact that it would burn in the atmosphere

What other options are out there?

1) Has anyone ever tried the XR5 with as realistic settings as possible? I remember one could adjust its ISP to a rather realistic setting. Launch the XR5 with a TX and then use the XR5 to go to the moon and back... that doesn't seem toooo much off for me right now. Is it somehow reasonable?

2) Ok another possiblity: using the shuttle fleet, it would be possible to launch and retrieve cargo from earth to LEO and back. If I use the shuttle fleet, i have two problems in my mind though:
- In this case, I would need to launch a space shuttle for every single cargo deliver which comes back from the moon. This seems like such a waste of money. Ok the shuttle could bring stuff UP in the same mission... but still... =/
- Lets say its rather reasonable to think about a lunar base in 2030, by then, the shuttles would be 40-50 years old! Unthinkable...

This is truely such a big problem, also for "real" spaceflight... every little Kg that we want to use in space must be lifted off from earth - which is so difficult. And to make its usage pay-off, there must be something brought back - which is so difficult too.

Damn...

 

[garyw]

What other options are out there?

Shuttle-A cargo pods.

These things carry 20t each and have parachute systems so if your aim is good you can drop these into the atmosphere.

 

[PriestLizard]

Shuttle-A cargo pods.

These things carry 20t each and have parachute systems so if your aim is good you can drop these into the atmosphere.

Hmm ya I already thought about that (got the idea from the stock scenario where you drop the pods into the ocean).

The problem though is: I'd have to drop the pods at a much more higher altitude than in the stock scenario, at like 80km. So aiming will be very difficult?
At least this seems reasonable. The shuttle would return to LEO from this lower orbit while the pods do their reentry and then land with chutes. Hopefully the pods have a good heatshield

 

[mcsquared08]

I am in the late stages of assembling a lunar base much like you are planning to. I started by building a space station in LEO with building blocks and mir-2. I used a series of ENERGIA launches with the buran-t to launch the components and a DGIV set on the lowest fuel, engine, and O2 settings. Then i launched tons of DGIV cargo and mounted it on truss segments at the station, where i then undocked the trusses, docked them with a DGIV and transferred to the moon. Theres nowhere near enough fuel to land the cargo, so i did a series of missions until all of the cargo was orbiting the moon, then did a series of missions to slowly bring the cargo down with a DGIV and universal cargo deck.
It is probably not the most efficient way, but i fugured there was at least a little degree of realism. Took about 20 flights, slowly picking away at it. I substituted the pile of cargo on the moon with a prelude base, and supply it with a fleet of 4 DGIV's all with the lowest settings. Thats my way, hope it helps somehow.

 

[Andy44]

You asked for realistic options. Shuttle A is not realistic. The Isp is magically high.

Your only option is a space shuttle-type vehicle, or to build cargo modules with heat shields and parachutes that can be dropped into the atmosphere alone.

As for launching a shuttle every time you want to bring something back from orbit, that's why it's called a "shuttle"; it was originally meant to be constantly flying back and forth to a LEO station, with a launch rate as high as 1 every 2 weeks. It was also supposed to be cheap. Didn't work out, but it was meant to do exactly what you're asking for.

That's why I've been thinking about an "alternate future" space shuttle add-on which would replace and improve upon STS.

 

[PriestLizard]

You asked for realistic options. Shuttle A is not realistic. The Isp is magically high.

Hmm. Can't deny that.

As for launching a shuttle every time you want to bring something back from orbit, that's why it's called a "shuttle"; it was originally meant to be constantly flying back and forth to a LEO station, with a launch rate as high as 1 every 2 weeks. It was also supposed to be cheap. Didn't work out, but it was meant to do exactly what you're asking for.

Alright. So maybe for my purposes I will just assume that the shuttle program worked out as intended. Of course you're right its basically exactly what I was looking for. Its just that in reality, every shuttle launch seems to be something "special" (and it is special) and every launch is a huge "project". It just seems to be way off reality to establish a cargo transport route from earth to LEO with regular transits like, lets say, cargo railways on the ground. We're probably many years away from solutions to make this possible.

@mcsquared08: Thanks for your post, it gave me some good ideas. Especially the truss with docked DGIV-cargos is a nice idea. This way, the DGIV can indeed transport more cargo than just within its payload bay. I will most likely copy this idea and use DGIVs to transprort cargo from the moon to LEO and back. The original space shuttle (or more likely shuttle fleet) will be used to bring cargo from ground to LEO and back.

Just wondering: does universal cargo deck work with the space shuttle? So it could launch DGIV payloads? I'm not sure but I think I remember that there was a problem... right?

 

[C3PO]

How "magical" are the engines on the TX launcher?

Otherwise I'd go with Energia/BuranT. If you want to bring stuff down, put a heat shield and shutes on it.

 

[T.Neo]

That's why I've been thinking about an "alternate future" space shuttle add-on which would replace and improve upon STS.

That would be awesome. I've always wondered what a serious second generation spaceplane would look like.

 

[Notebook]

Reaction Engines have a study for an Orbital Assembly Facility, might give some more ideas:
http://www.reactionengines.co.uk/downloads/Design%20of%20an%20orbital%20base%20facility%20for%20complex%20missions%20IAC%2008%20D3.3.1.pdf

You get an animation as well...

http://www.reactionengines.co.uk/skylon_ops_anim.html

N.

 

[pattersoncr]

Well, at the risk of cementing my status as a Greg Burch broken record, you could use the [ame="http://www.orbithangar.com/searchid.php?ID=3124"]Big Space Plane[/ame].
It's somewhat near future (2050's-ish) and doesn't really use any handwavium although it is built out of unobtanium.

 

[Andy44]

The Skylon is a very cool idea, although its current configuration doesn't have the payload capacity of STS. I wonder if this would really work? If so it would make a mockery of NASA.

I also like the passenger module idea. That was one of my ideas for a STS 2.0. Although my passenger module would essentially be an escape capsule, in the event of a catastrophic breakup during launch or re-entry I'd want the passengers to have a fighting chance. Something that can withstand being ripped from the fuselage, stabilize itself to the relative wind, shield itself from heat and parachute itself to the ground.

 

[ijuin]

When you're talking about reentry, the issue is not so much about the module surviving a breakup of the spacecraft as it is of the HUMANS surviving the violent accelerations that would necessarily happen during the breakup and brief tumbling before it stabilizes itself.