— Donald

It’s called ISS.

The sequential approach you reference won’t work. Assuming NASA could indeed develop a CEV & launcher in 5 years is questionable given their past performance on large dollar programs. But granting they perform this miracle, the next 8 years leaves the CEV waiting for someplace to go or something to do. That just isn;t realistic. Griffin has selected the configuration to maximize existing infrastructure, etc. It also means he inherits the standing army behind that infrastructure that still needs to be fed. At $2-$3B per year, the developmnet schedule for the rest of the architecture is stretched another 30-40%. We’ll end up with the same situation we are in now, the CEV flying to a meaningless outpost at LEO just to maintain critical skills and hopefully public interest so that funding streams can be maintained. Better to get to the destination as soon as possible and demonstrate that there is something worthwhile there to whet the appetite for more.

However, I sincerely hope that I will never have the opportunity to say, “I told you so.”

— Donald

That plan sounds as if it might be cutting things a bit close but I am in no position to argue that it is impossible, I don’t have enough hard information to make that call. It boils down to my trusting Griffin. Which at this point I do.

It doesn’t matter what you “need.” In our time and place, all that matters is the money available, and $8 billion is the money the nation has decided human spaceflight is worth. If it doesn’t fit in that constraint, it literally won’t fly.

So, rather than continue _this_ debate, how would you make developing and maintaining the CEV; trans-lunar vehicle; lunar lander; return vehicle; lunar surface module; lunar surface equipment; the HLV; an additional medium-class vehicle; an orderly shut-down of the the Shuttle program; finishing the Space Station or at least maintaining it as is; and anything I haven’t thought of all fit within $8 billion a year? If you can’t, what would you cut?

I’ve given you my solution: strip it down to modify the EELV; build “light” CEV; light lunar vehicles; lunar base and equipment; Shuttle shutdown and maintain Station; plus probably signficantly higher operations costs than your model. I think there’s just a chance you could fit all that into $8 billion a year, especially if you move Shuttle shutdown forward and commercialized Space Station maintenance.

How do you fit your model into the resources available?

— Donald

For an example let’s say we want to launch Apollo hardware using smaller vehicles. I don’t know all the Apollo craft weights offhand so for this example I’ll just say that it require an EELV each for: the LM decent stage, the LM ascent stage, command module, service module, and a stage to push all this to the moon since there won’t be a Saturn 2nd stage to do so.

Now I know it may be an exaggeration to say that each of these pieces of hardware are heavy enough to require its own launch vehicle but I’m trying to demonstrate a point I think is overlooked too often.

If you launched all this Apollo hardware in this manner each vehicle would need to be modified such that it could be assembled remotely on orbit.

Say we launch the LM descent stage first and then the ascent stage. They have to “find” one another and dock in space, something they were not design to do in the Apollo program. This will require weighty and expensive modifications, RCS, Radars etc. plus extra electrical capacity to operate these things and keep the craft alive while being assembled and waiting on the remainder of the vehicle “stack”.

The same applies to launching the command module, service module and the trans-lunar injection stage.

My point in this admittedly fictional example is that when you design for on orbit rendezvous, docking and build up of a orbital complex you have to build in things that add weight and expense that are only useful to you during that stage of the mission. After the assembly process all those extra RCS assemblies, rendezvous radars, docking rings, airlocks, etc. are just dead weight.

Having a launch vehicle that is large enough to launch bigger “chunks” at a time minimizes the amount of dead weight rendezvous equipment you need.

Launch four EELVs, sure, you’ve spent more in launch costs, but to fly an additional payload you only need the incremental cost and effort of one more EELV. No, it’s not free, but it is more flexible.

— Donald

HUH? We can launch just as many small vehicles we like? Someone is giving them away??