Skylab + Shuttle = Alternate History

[Usonian]

I am preparing to update Skylab1973: Improve the meshes, add Saturn V launch scenario(s) and add historically based reboost, rehabilitation and reuse scenarios using the Shuttle. I haven't played much with the Orbiter Shuttles, so I have a couple of start-up questions to ask the STS experts out there:

The 1978 Skylab Reuse study shows the Soviet style "androgenous" docking ports with petals turned out. On Orbiter's stock Atlantis the petals are turned inward. Do any of the Shuttle addons (Fleet, Ultra, others?) show the old-style petals-out docking ports? Why and when were the petals changed? I am tempted to show the petals turned out on my add-on, regardless, it just looks cooler.

How much difference is there in payload attachment points in the various Orbiter Shuttles? For a given payload, will I need to work up separate configurations for the stock Atlantis, Shuttle Fleet and Shuttle Ultra? I would like my addon to work smoothly with all of the available Shuttles. I am just trying to get a grip on the scope of work in front of me.

 

[Urwumpe]

The 1978 Skylab Reuse study shows the Soviet style "androgenous" docking ports with petals turned out. On Orbiter's stock Atlantis the petals are turned inward. Do any of the Shuttle addons (Fleet, Ultra, others?) show the old-style petals-out docking ports? Why and when were the petals changed? I am tempted to show the petals turned out on my add-on, regardless, it just looks cooler.

So far no Shuttle comes with the old APAS-74 docking port, but in Shuttle Ultra, we can, at least in theory, implement such a docking port, after we have done implementing the optional ODS. An Apollo style docking port would also be possible in theory, but I doubt it is fully compatible to the Space Shuttle in reality.

The petals changed in the early 1980s by russian engineers as docking port for Buran and Mir. The new APAS-89 has some very important qualities:

• Smaller outside diameter.
• The mechanic elements are now on the inside of the docking tunnel, so maintenance turned from EVA to IVA.
• More robust alignment.

The new APAS-89 is thus the better production version, while the APAS-74 was more like a prototype.

How much difference is there in payload attachment points in the various Orbiter Shuttles? For a given payload, will I need to work up separate configurations for the stock Atlantis, Shuttle Fleet and Shuttle Ultra? I would like my addon to work smoothly with all of the available Shuttles. I am just trying to get a grip on the scope of work in front of me.

We have not yet decided how to do the payload interfaces for Shuttle Ultra. It will be very likely unlike the Shuttle Fleet attachment(s), but I can't tell you yet how far different. If you have demands and requests, you can voice them now and we can consider them in our design work. We can't please everybody, but I would say, getting integrated early in the process will be an advantage in any case.

Our main goal is to get the realistic interfaces inside the VC. We develop means for custom payload panels in a future release currently.

 

[Usonian]

Thanks for the quick reply!

I will be using Spacecraft3, so my choices for securing a payload to a Shuttle are attachment points or docking ports. Are there any other ways of joining vessels in Orbiter?

If by "unlike the Shuttle Fleet" you simply mean that the location Ultra's attachment points will differ from those in the Fleet, then that's something I can easily handle by offering alternate configurations for each vessel.

This will, of course, obligate me to play with both add-ons enough to learn the differences - such a burden - obligated to play with Orbiter.

 

[Urwumpe]

The main difference will be the format of the scenario file. Attachments will get used, but for example we still have the option to use Kulchs Payload system in the discussion.

What is nearly accepted is the idea to use Mission definition files for defining payloads, payload configuration and flight plan information instead of storing this constant data inside the scenario file. As we will have quite many scenarios of the same mission, this will be quite handy.

 

[santy86]

Hi guys i was thinking about the Saturn INT-21 to launch skylab in orbit. I wrote some code and maybe i will finish soon a preliminary module for the rocket. Maybe it can be useful, but i don't know how to make meshes . In addition i am thinking about an autopilot, but i will add it later on, because i am also busy with studies.

Finally, does somebody know where to find aerodynamic characteristics of the rocket saturn int-21? Is it worth to take them into account?

Regards,
santy

 

[Andy44]

In addition to the different docking port design, you also have to think about the different life support systems. Skylab uses an Apollo-type system of low-pressure, pure oxygen, while the Shuttle uses a standard atmosphere of almost sea-level pressure and 20% O2.

To move from the shuttle cabin to Skylab means pre-breathing O2 and air-locking in. Your best bet may be an adaptor module which links the two docking systems and also serves the required airlock function. I swear I have seen a drawing for a proposal for such a module, but I can't find it on astronautix.

 

[Usonian]

Andy44,

Here is a link to the 1978 Martin Marrieta study:

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790075817_1979075817.pdf

The proposed system is exactly what you describe, an "Interface Module" with an airlock section. The free end of the I/M also had an adapter section with multiple Shuttle-type docking ports for later addition of a "power modual" with large solar array, Spacelab-type logistic modules and experiment pallets - all of which I would like to recreate (re...?) I mean create.

 

[tgep]

Here's another good link with many other referance links itself.

http://www.astronautix.com/

 

[Andy44]

Yeah, Usonian, that's the paper I saw before! Lots of cool stuff there for adon development! I don't know if you're old enough to remember the 1970s, but I remember all the excitement about the upcoming shuttle program and the cool stuff they had planned to do with it. I also remember all the buzz about Skylab's demise and the jokes about it.

 

[Usonian]

I don't know if you're old enough to remember the 1970s...

:rofl:
My earliest memories of news events: The Cuban Missile crisis and John Glenn's flight. The 70s are easy - remembering what I said last week is the challenge.

I miss the palpable public excitement that space flight used to generate. That pretty much fizzled out during the 70s. For me currently, the Mars Exploration Rovers come nearest to recapturing that feeling.