President Bush to announce manned trip to Moon, Mars (merged) (1 Viewer)

[Andrew Testa]

Cees,



Ironically enough, this was the exact blueprint for what is now the ISS. It was originally envisioned as a central hub for all those activities, as well as satellite servicing. Unfortunately, all of the different capabilities fell victim to cutbacks and redesigns, until we were left with the core station and none of the many duties it was supposed to be a hub for. But the experience has taught us that many of those different activities are incompatible with each other. For instance microgravity research requires that there be no vibrations whatsoever. On ISS that means the crews can't even use the exercise bikes while some experiments are being run, so anything major like repairing satellites or assembling spacecraft is right out. The ideal situation is to have multiple platforms for specific uses: unmanned factory modules for research that requires pristine microgravity, manned modules for hands-on research and human physiology research, and repair stations where a robotic tug can bring satellites automatically to be either fueled autonomously or to await a human crew to arrive via CEV to perform repairs, then return. Spaceship construction out of separate modules doesn't require any kind of facility; we can stack modules together in LEO just fine. The big all-in-one space station may one day be an advantage, but for our current technology it's too much for the jobs required. But hey, it's just my opinion.

Jack, yes, I've noticed your current support for the capsule idea. I'm pleased you can see the positives to the concept, even though it's not as Buck Rogers as a sleek winged vehicle. If I had anything to do with it, then I'm glad I was able to clearly describe the benefits (can we get a group hug here?).

Andy

 

[Lee L]

Andrew, using the example you cited above with the 5 meter diameter capsule, what is the comparison between its area and the area for crew space in the current shuttle?

 

[Andrew Testa]

On a different tangent, I found something interesting while looking up the specs on the Atlas 5 and Delta IV boosters. Both systems have several variants depending on the payload size, mass, and destination. Most of the variants involve the size of the fairing and the number of strap-on solid fuel motors attached to the common core stack. Both also list a Heavy variant which consists of three common core stacks attached together in line, with the upper stage and payload fairing on the center stack. Boeing advertises 29,000 lbs to GTO; twice the capacity of the largest Delta IV Medium. LEO capacity is a whopping 58366 lbs, comparable to what the Shuttle can haul. Rollout occured this December and first launch is expected in summer 2004. Whole bunch of pics can be found at Boeing's site. Here's a good pic:



Note this is only the booster. The upper stage and payload fairing are not mated yet.

The Atlas 5 Heavy is relatively similar in appearance. The advertised capacity is 28,600 lbs to GTO. The Atlas 5 500 is rated for 45,000 lbs to LEO, so I suspect the Atlas 5 Heavy to be able to haul significantly more than the Shuttle to LEO. Regarding my post above about the size of a potential capsule, I found that the Atlas 5 Heavy has an increased fairing diameter of 5.4 meters (17.9 ft) so an additional foot is available for a slightly larger capsule, and the volume increase is 235% of the Apollo vs the 123% I calculated above. You can put a big vehicle on this thing. Here's a pic of the Atlas family:



So it looks like both of the existing launch systems have a heavy lift variant that can rival the Shuttle to LEO. Anything heavier than that will require a new launch vehicle.


Andy

 

[BrianShort]

Hmmm so how much will one of those run me?

Could they make a variant that had 3 or 4 strap on boosters around the core for heavier lifting?

Is there any serious research currently being done into alternative propulsion methods for lifting off of earth, or will we be using chemical based propellant for awhile longer?

Brian

 

[Jack Briggs]

Impressive stuff, Andrew. Who needs an Ariane V when you got stacks like these?

Also, did you know that a few people in the Russian space community are already talking about hopping on the new space-initiative bandwagon -- and are mentioning resurrecting the abandoned Energya launch vehicle? I made a joke to that effect a few posts ago, and now I read it's actually being floated as an idea.

 

[Andrew Testa]

Lee,

That's an excellent question, and I had to do some digging to find the answers. The Apollo Command Module had a habitable volume of 210 cubic feet. The Shuttle has a crew cabin of 2,625 cubic feet. Quite a difference. If a new capsule was proportioned exactly like Apollo and was the larger size in my post above, the crew volume would be ~500 cubic feet. Only about 1/5th the volume in the orbiter. But, that assumed that the CEV capsule was shaped like Apollo; that it is a cone slightly shorter than it is wide. That may not be the case. It may be longer with a gentle taper and then a blunter nose. But it's unlikely to have an interior volume as large as the Shuttle.

Andy

EDIT: btw, my one-person cubicle has a habitable volume of 240 cubic feet.

 

[Andrew Testa]

Brian,

How much ya got? They don't exactly advertise prices on the web! One doesn't just buy a booster, one buys a "launch services package" that includes everything from picking the right booster to command and control facilities to buying insurance. I'd plan on probably dropping anywhere from $10M to $50M on the full package. I'm sure the raw booster cost is buried in the invoice somewhere.

I suppose it might be possible to add more of the common core stacks if the structure could handle the launch loads. They currently add multiple solid motors to the core stacks, so one path may be to add more or larger solids. But I don't see any reason other than structural integrity problems with more core stacks. Of course the more core stacks you have the more complicated the structural analysis becomes. And for now chemical propulsion is the only way off this dirtball. There are a fair number of propulsion systems in work for space duty once you get to orbit, but they don't work for lifting you off the ground. Short of Orion (very small nuclear explosions happening several times a second under a reaction plate), we're stuck with chemical.

Jack,

Yeah, the design teams at the Russian centers were pretty quick to claim they had designs already to go and were looking forward to a call from the Americans. I find it hard to believe that a space agency that begs for money to build one more Soyuz, and delayed ISS by two years because they couldn't afford to finish the service module, is suddenly going to tool up the Energya line and build interplanetary vehicles. It's a lot of bravado and hot air.

Andy

 

[BrianW]

If we gain the capacity to launch over 50Klbs into LEO, then this is getting pretty exciting.

But, alas, the Hubble... It's given us more science and understanding than any other instrument, ever. If this is the path we choose, then I hope we commit to it, stick with it, and get it done right. I can't express how utterly disappointed I'll be if we cancel Hubble's last visit to pursue this path only to later have the plug pulled on our infrastructure construction by Congress or a later administration.

And speaking of telescopes and humans on the Moon, Andrew, do you know if NASA has entertained any notions of building an observatory on the Moon? With all the multi-story, domed, stadium-sized lunar habitats NASA plans to build, with moving sidewalks, personal rocket packs, and huge kinetic sculptures in each module's atrium, I would think that there could be some resources that could be devoted to building a modest observatory.

Jack, I think your Energya joke is still funny.

 

[Jack Briggs]

You know what one of my all-time favorite novels is? Arthur C. Clarke's utterly charming 1951 story, Earthlight. If you love the Moon, you'll love that novel.

 

[BrianW]

That's one of my favorite's as well, Jack. One of Clarke's most touching short stories comes to mind as well: Laika, a heartfelt tale about fond memories of a long-gone, loyal, canine companion, set in an age when the establishment of human presence on the Moon is just beginning to pay off - both subjects that I find deeply compelling.

 

[Andrew Testa]

It looks like some preliminary ideas are coming out from the assumed major players. NASA Watch had a link to some CAD renderings from Boeing for a CEV concept. There's very little text, so you have to fill in the story yourself. A summary:

• - Completely modular system: vehicles, stations, landers, all composed of combinations of same core modules
  - All modules launched on Delta IV Heavy (pictures in previous post!)
  -CEV assembled in LEO
  -CEV composed of capsule, power module, and two Delta IV upper stages as translunar boosters.
  -Autonomous cargo vehicle, which also serves as core of inflatable crew habitat, similar to TransHab.
  -Small modular lunar orbit station to control vehicle assembly
  -Lunar lander composed of modular components on a landing base
  -Mars vehicle concept using a scaled up vehicle using the same modules.

Now it's Lockheed's turn to show some ideas. I must say I am incredibly impressed with this concept. It takes the modular infrastructure concept to heart and shows what it can do. This is what I had been hoping to see.

Andy

 

[Jack Briggs]

I had already read about the R421 lunar-lander concept at a link on Cowing's NASAwatch site. And I agree, Andrew, this is taking "modularism" to new heights. Some of those things look like real spaceships!

 

[BrianShort]

I like the idea, but the crew capsule looks too... Apollo-ish...

There must be designs for a capsule type system that don't look like the Apollo capsules, right?

Can't wait to see how this program evolves, and what Lockheed-Martin comes up with.

Any word on when this committee or group or whatever that will start planning the details of the mission will be formed? I'm talking about the one that's going to be headed by the military guy. Don't remember the name.

Brian

 

[Lance Nichols]

BrianShort, considering the amount of design and testing that went into the Apollo reentry vehicles I would be surprised to see initial ideas, or even "finished" concepts, that diverged from the Apollo style capsule.

You need a ballistic reentry shield that is shaped to offer some limited aerodynamic control during re-entry, a place to seat crew, and a place to store and deploy the drouge and main 'chutes.

These CAD drawings are really just sketches. End result might look different but then again, if it worked before, why change it too much? personally, I like the ideas represented here. Keep as much the same as possible, add modules to do specific tasks if the main crew unit can't.

 

[Andrew Testa]

Why?

Seriously, Why should they look different? The intended purpose is identical, we have experience with a capsule reentry vehicle, it works. Don't fall for the trap that because it's shaped like Apollo that it is Apollo. They will be completely different spacecraft, and in this capacity merely one component in a larger habitable system, as opposed to the capsule being the only habitable space in Apollo. If all you want the vehicle to do is bring people into orbit and then return them, then this shape fits the bill.

Look at the capabilities of the system with all of the modules. Don't focus on the capsule to the exclusion of the really ground-breaking parts of the concept.

Andy

 

[BrianShort]

Andrew: I understand that functionally it's probably great. I just like pretty spaceships and I don't think it's all that pretty Though granted, once it's bundled together with other modules it begins to look a bit better.

I wonder what the general public will think of a capsule based system...

Brian

 

[Jack Briggs]

Oh, so it's the styling you object to. Well, I think you're looking at sketches of the 2014 models. I'm sure the 2020 models will have snazzier features (I'm hoping for racing stripes).

Remember a little Stanley Kubrick movie with a buncha spaceships and monkeys and pretty colors? Well, critics were taken aback by the nonaerodynamic shapes (except for the Pan-Am space shuttle) of the spacecraft depicted therein. The great filmmaker gave 'em a dose of reality. And here we are, 36 years later, and the spacecraft in that film still look futuristic -- sorta like the stuff in Boeing's illustrations.

The otherworldliness of these concepts is alluring.

Andrew, isn't it fascinating how freeing oneself of the STS (or any of the replacements considered in the days of the SLI) in thinking about our nearterm future in space is so damn liberating? Everything one considered in a future space infrastructure had to be tied in somehow to the capabilities and limitations of the present Space Shuttle paradigm. Setting the STS aside seems to open up so many possibilities, and that's what's exciting about NASA's new directive.

Now, I only hope the whole shebang survives Congressional scrutiny.

 

[BrianShort]

Jack: Oh yes, I love Kubrick's designs. The Discovery (that's it's name right?) is beautiful. I should try to find a good scale model of that, actually. I should watch 2001 again sometime

Brian

P.S. Maybe they can have flames and other cool art airbrushed onto the new spaceships Consult Jessie James for other styling details.

 

[Andrew Testa]

That's all we need, MONSTER SPACESHIPS!

Hey, it's got a VASIMIR propulsion engine, an inflatable crew habitat, and a GLOWING TIKI HEAD THAT SPOUTS FLAMES!

Jack,

More seriously, I completely agree that once the shuttle is taken out of the critical path an enormous array of possibilities show up. But don't think it's gone completely: the payload diameters on the Atlas and Delta are sized to be compatible with shuttle max payload diameters, so that any of the systems could launch a given payload (such as TDRS, launched on orbiters and expendables). Also the OSP proposals that will likely be transformed into the CRV crew module are all sized to be launched in an orbiter. So, most of these modules in the boeing design could have been brought to LEO in an orbiter. However, the hands-on assembly paradigm that comes with the orbiters would have made the process less modular and certainly far more costly and time consuming. Shifting to an expendable vehicle frees you from that and makes a simpler rendevous with no EVA a requirement. So in a perverse manner the ease of EVA and flexibility of assembly options with the robot arm led to orbiter projects being far more complex than required. If it had been harder to mate ISS components, we would have a simpler method of doing it. Better vehicles will be the result, but the legacy of the shuttles will be a part of the system long after they are retired.

Andy

 

[Jack Briggs]

Well, you bring up a point (re "legacy") I have wanted to ask you about: Even though VentureStar and the later, watered-down, Space Launch Initiative designs are now back in their drawers, locked away, don't you think all that has been learned (and will be learned in the remaining six years of service) from flying and operating STS will have future applications? Or will it all have turned out to be a technological dead end?

I think -- I'm almost certain -- that winged, reusable manned Earth-to-LEO transports will return, and that the STS legacy will provide a voluminous database from which to mount such a project.

After all, for decades the rigid-framed airship was considered a technological dead end in the aftermath of the LZ-129 Hindenburg disaster of 1937. Yet, lo and behold, the rigid-framed Zeppelin has been making a comeback (the LZ-NT07). Might the same hold true for the flawed but beautiful machine that is the Space Shuttle?