Lets use the example of 4 EELV launches: 1. Lunar Lander, 2. TLI stage, 3. TEI stage, 4. CEV. How many pads do you have to launch from? Presently there is only one pad that I’m aware of that is capable of handling the Delta IV Heavy. So you have to roll out the first rocket/payload and launch it, now start the clock (or calendar). How long does it take to get the second, third and forth payloads out to that one pad and launched? I’m guessing that at best the CEV and crew would launch no sooner than six weeks after payload one went up. And if you build or modify another pad to handle the heavy EELV to increase launch rate you eat into that $10 billion you’re “saving” on the HHLV.

A side issue on this is that the longer it takes to complete assembly the higher the first payloads have to be lifted so that it’s orbit won’t decay before the last arrives. This higher orbit requirement cuts into the payload capacity of the lifter.

On the other hand an STS derived HHLV could be built that would launch from Pad39 with little to no modifications to the pad, and crews could launch from Pad 37, which will already handle the current Delta IV Heavy. Of course some modifications would be needed to that pad for crew accommodations.

Also on the political side of this (as a counter to your argument that STS derived costs would kill it) one thing STS derived has going for it is a ready constituency in Congress. I’m sure that there’s a number of Senators / Congressmen would want to see continued production of external tanks, SRB’s etc. Just as most of the politicians who bemoan the death of Hubble do so because of the money it brings to their continuants (rather than a true love for Hubble itself), the same would be true with STS components.

Now I’m not saying that STS derived heavy lift is a clear winner, but just that I don’t think EELV’s are a clear winner either. Both options need to be studied very carefully.

The figures higher in this thread are actually less conservative than I was using. If it takes four to eight EELVs to do a lunar mission, using the figures above, that’s one to two billion dollars. That means that just by forgoing development of the HLLV, you could pay the launch costs of five to ten lunar missions.

I am _not_ arguing that we should not develop an HLLV, I am talking about the order. Get something on the moon that needs resupply ASAP with whatever is available right now. Then, you’ve got a market. Then, you can use that to justify the HLLV and optimization of the logistics steam.

Mir is a good model. Russia has launch vehicles today because Mir existed when the Soviet Union collapsed, and also because someone needed them for their own station. Mir, and later the ISS, were (and are) markets that keep a significant fraction of the world’s launch industry busy today. Likewise, the existance of the ISS is a good part of the reason the Bush Administration could not seriously consider dropping human spaceflight as one of their options post Collumbia.

It’s also the lesson from human history. If you want to open a new frontier soon, get something — anything — up there that needs resupply and do it as quickly and dirty as possible. Then, once you’ve got a market, you can start worring about getting costs down.

Finally, I don’t see why this needs to be as logistically complex as you’re making it sound. Remember that Apollo involved at least two dockings (LEM extraction, then LEM / CM for the return to Earth). The four elements I listed earlier should all be pre-packaged sections, ready to dock-and-go. Once everything is launched, it shouldn’t take more than a day to assemble in orbit, launch the crew, and start the mission.

— Donald

You may be right but I think the same could also be true of using EELV’s, but for different reasons.

If it takes 4-5 launches and a month or two of on-orbit assembly to do what Apollo could accomplish in one launch and a week or two, and then it takes dozens of launches and many months/years to establish even the most rudimentary base on the Moon I am afraid the political will may erode due to impatience. And those dozens of launches at $170 to $250 million each will start looking very expensive for comparatively little result. Congress likes to see quick results, and the only way I see to do that is with some sort of heavy lift capability.

— Donald

On revolutionary, single stage to orbit, hi-tech all reusable “stuff” they do indeed. Building an STS derived heavy lift involves none of that. Or should not, but if someone gets cared away with gold platting….

>>>> My wild guess is that it wouldn’t take more than four per mission (empty CEV, upper stage and fuel, lunar lander, return stage and fuel).

And another to launch the crew? Anyway, at 4 launches that’s over a billion dollars at current Delta IV heavy costs (254m ea) and around 700 million at the best estimated cost (170m ea), and I’m betting that even if the launch rate was 30 DIVHs a year you’d never see that $170m rate.

Also DIVH could loft at most a roughly 80-ton complex in 4 shots, STS derived could loft a more capable 100 plus tons in one shot. Although I would hope the crew would be launched separately on an EELV, but that adds even more capability with a total of ~120 or more tons in orbit.

>>> $10 billion plus a new launch vehicle would cost.

Maybe I have too much faith in NASA, but I can’t imagine that an STS derived HLV would have to cost that much. It possibly would if they went the inline route with the engines under the ET, and the payload on top. But doing so increases the lift capacity even more and is actually a good idea, plus while you’re at it re-design to use RS-68’s rather than SSME’s.

This, I disagree with. If NASA gets side tracked into launch vehicle development — and all NASA’s tendancies are to do just that — the VSE will die the same slow death that every other recent plan has undergone. We have brand new, state-of-the-art expendable launchers in the EELVs and Ariane-V. At least the initial lunar missions should use those. My wild guess is that it wouldn’t take more than four per mission (empty CEV, upper stange and fuel, lunar lander, return stage and fuel). Even if it took twice that, we could launch two or three actual lunar missions for the $10 billion plus a new launch vehicle would cost. We could probably even start the initial emplacement of a base.

This would kill two birds with one stone. It would increase the flight rate of the EELVs, reducing their costs for everyone. It would produce early results, thereby justifying later development of the HLV.

In any case, it is my understanding that SpaceX plans to develop a Saturn-V class vehicle as their third-generation project. If the first flight goes well, NASA should probably help them along rather than do it themselves.

Cargo delivery to LEO and escape to lunar orbit (essentially the same as GEO transfer) are mature industries that don’t need NASA’s help except as a market. This Democrat says, farm it out to industry. . . .

— Donald

I am coming to favor a gold plate, honest to God, crew only RLV to ferry humans to LEO;

combined with

a non-man rated HLLV cargo lifter having the largest possible fuel to dry weight ratio we can achieve.

For example, start with a Thiokol SRB which is 85% fuel and 15% structural mass. Swap in composites and other plastics for aluminum and push the 85/15 towards 90/10 or greater. A 4 segment SRB has 192,000 pounds of strutural mass. If you could go from 85/15 to 90/10 that would add 64,000 pounds to your first stage payload capacity. 80,000 pounds if using 5 segment.

Build a shuttle C or related SDV using a pair of plastic 5 segment SRBs and you can add 160,000 pounds to the 2nd stage payload, in other words in addition to what astronautix says SDV can lift, today.

Adding 160,000 pounds of 1st stage payload to an SDV might very well cost-justify throwing away the SRBs after each launch.

= = =

Total reuseability and man-rated reliability or build expendables with as little dry mass as possible and never let crew ride on them.

After all, large amounts of the mass needed for Moon and Mars is simple bulk goods such as fuel (LH2, methane & LOX) and water (for rad shields and drinking) and food.

Why slog fuel in a Mercedes class RLV?

True, but I think NASA realizes that. And since the Shuttle is to remain in service until 2010 we have 5 years to make a decision on how whether or not to build an STS derived HLV.

Personally I’m about 90% convinced that we need a 100 ton to LEO class lifter if we’re going to have a serious Moon program.