Space engineering is sort of an archeological endeavor. It moves at a slow, historical pace, like eons of ancient history. All macro-scale space engineering thoughts have already been thought, decades ago, and we dig these old bones and fossils up again.

NASA may be faced with a stark either/or, the choice of either abandoning the International Space Station or getting heroic and creative with the three remaining Shuttles and with the EELV’s.

“… plus the EVA training issue (each module requires multiple EVAs for assembly…” you say?

I reply that NASA is either going to have become truly gritty and heroic and do stuff that is NOT BUSINESS AS USUAL, or else America will end up abandoning the jolly ship ISS.

What are the other problems?

(1) Some shuttle payloads attach along their side;

(2) Some payloads need electrical power en route;

(3) The payloads lack the orbital maenuvering capability to place themselves with reach of the ISS’s robot arm.

How to deal with (1) and (2)? The Delta IV heavy version is advertised to be able to lift 48,000 lbm. to the ISS and to have a 5 m. diameter fairing available. None of the ISS modules are that heavy. There might be enough mass margin available to build a payload cradle to adapt the payload load path to fit inside a 5 meter diameter fairing.

We’ll also improvise an electrical power supply supply that will fit inside a disposable EELV shroud for these payloads . One assumes that the adapter cradles and electrical power packs could be removed manually upon arrival at the ISS.

What do these ISS modules need en route electrical power for, anyway? Is electricity only needed to support Built In Test, or do some modules have to maintain ISS cabin pressure and temperature while en route, or what?

… Current propellant budgets for shuttle-ISS flights can support two rendezvous reliably; three is a stretch. …

Suggested fix: refuel a Shuttle’s Orbital Maneuvering System at the space station. Yes, I know that the OMS uses dangerous, nasty hypergolic propellants. But heroic deeds, instead of NASA BUSINESS AS USUAL may be needed if the International Space Station is to be completed.

Oh, someone is going to ask, why fool around with launching space station modules on EELV’s? The answer is, to minimize the number of additional Shuttle round trips needed to complete the ISS.

And in reply to the question, don’t we have to wait until we have a further improved External Tank avilable to launch any more Space Shuttles? My opinion is, no, we have to keep on launching Space Shuttles, even with the External Tanks we have now. Otherwise, NASA manned spaceflight is going to grind to a halt under an ignominious cloud of failure.

I think the public might accept the loss of another Shuttle if the Shuttle’s crew were perceived as trying to do genuinely heroic deeds, as opposed to another Mickey Mouse Club STS mission in which a crew of seven astronauts once again proves that soy beans will sprout in microgravity, whereas humans do indeed get kinda dizzy if spun around in a swivel chair while in orbit.

besides, if we lose another Shuttle, then we’ll know that it’s definitely time to retire the Shuttle program. This will simplify future decision-making. :]

This was analyzed in 1990 using Shuttle-C in place of EELV. It was found to be impractical due to the large number of shuttle rendezvous required.

Each additional module delivered in this manner requires two rendezvous (one to get the module, the second to deliver it to ISS). If you assume the shuttle is launched full and goes to ISS first to drop off its first module, that’s a total of three rendezvous for two modules, five rendezvous for three modules.

Current propellant budgets for shuttle-ISS flights can support two rendezvous reliably; three is a stretch.

Throw in the issues with module survivability in free space with no power or thermal control, plus the EVA training issue (each module requires multiple EVAs for assembly), and this becomes a non-starter.

Hasn’t that been the problem with the VSE since Day 1? The purpose has always been vague, and has always substituted means for ends. But then, that was the trouble with the station and (to some extent) the shuttle also.

… and I see no mention of the mission objectives. It’s got an outline of the requirements for the *means of transport* of 4 humans and/or 15Mt of cargo to the moon. What is the 15Mt, and how much will it cost? What will 4 astronauts do there? What is it all for? (In situ regolith processing, a base with a telescope, a Motel-6 with saunas, U-Haul trucks… take your pick) Besides, 7 days on the moon a year is kind of short, isn’t it (for all these gigadollars)? What exactly can be done during this short time in terms of the “infrastructure”? What *is* this infrastructure? (nuclear stations, golf courses, what???!) Nothing. Just a brief notion of “will support 4 humans for seven days… To recap what is it all for? What *is* the mission of the 4 NASA people spending 7 days a year on the moon?

p.s. btw, here’s another slide from that presentation (apparently, judging by the time-stamps) re: budget http://images.spaceref.com/news/2005/06.04.05.esas.budget.lrg.jpg

!!!???

All I see is bullet point engineering (an inferior subset of PowerPoint engineering). It is one step up from a work of fiction.

There’s no way to assess whether or not the morsels of data they deal out have been properly studied at all. This data could all be the opinion of a few engineers at Marshall and you’d have no way to tell the difference between that and a real study.

The bullet points do say:

* CEV accomodates up to 6 crew for ISS missions, up to 4 crew to the lunar surface, and up to 6 crew for Mars return

However that is listed under technical _groundrules_ and _assumptions_.

The rest appears to be a restatement of those assumptions in the context of whatever limited analysis they did conduct.

Given the Shuttle and the Space Station experiences, don’t you think the burden of proof should be on NASA to prove they aren’t fiddling their technical requirements for pork-related ends?

PS. my name is Parkin, not Parker.

Moving the ISS is technically possible but is impractical. Some have suggested moving the ISS to an inclination angle closer to 28 degrees so as to make it easier for us and harder for the Rooskies to launch to the International Space Station, ha ha ha.

Additional space stations? Not likely. There have been suggestions to put a small space station, perhaps an inflatable, at libration point L1 near the Moon.

My suggestion is construct and maintain a rather robust, re-fuelable lunar orbit to lunar surface spacecraft. This craft would be able to carry three or four humans at a time to the lunar surface, or robotically load, land, and unload several tons of cargo. This lunar lander also be used for suborbital point to point lunar travel. I suppose you could think of this fancy lunar excursion vehicle as the core of a de facto lunar space station.

The HLV’s and EELV’s are all fine and will be necessary for any plan, but we need the space tugs, the lunar transfer stages, the lunar landers and the permanent bases to keep space exploration moving forward.

Are you saying the CEV should have a crew of 3 simply because Apollo had a crew of 3? Isn’t that pretty arbitrary in itself? And as MrEarl stated above “If we’re just going to redo Apollo what’s the point?”

The current ESAS study referenced above specifies “four Crew to the Moon plus 500 kg of cargo.” Four is not a whole lot bigger headcount than Apollo’s two or three, in my opinion. Also, I don’t think an HLV is an absolute necessity to send four astronauts to lunar orbit.

My concept of operations to “top” Apollo is to send no more than three or four astronauts at a time to the Moon, but stay for longer and longer visits. The first new lunar expedition will have a pressurized habitat — a Moon shack — with which to remain on the Moon for 7-10 days. Subsequent Moon visits could stay longer or overlap so as to have perhaps eight astronauts on the Moon. Continuously manned Moon base? Yes.

Caution: one thing that’s gone wrong with the both the Shuttle as well as the ISS is specifying that it must have a crew of six or seven or eight at time in order to function. It seems to me that astronaut population explosions imply larger and more troublesome spacecraft. … What’s the real agenda here, to build HLV’s that can lift six man capsules or to return to the Moon sooner?

You’re still neglecting the P3/4, S3/4, and S6, and still ignoring the difficulty and expense of the space tug required to get all the modules to ISS once the ELV has delivered them to LEO.

Here’s a suggestion for completing the ISS: Use EELV’s to launch cargos to fly in formation with the space station. Then launch a Shuttle. Use the Shuttle as a space tug to gather the payloads and mate them with the ISS.

You’re still neglecting the P3/4, S3/4, and S6, and still ignoring the difficulty and expense of the space tug required to get all the modules to ISS once the ELV has delivered them to LEO.

My prediction stands.

Here is some info that was released, excuse me I should say “leaked”, just a few days ago:
NASA Exploration Systems Architecture Study Overview Charts

The above goes into some detail as to the mission and the expected capabilities of the CEV as well as some mention of moon base infrastructure. And on the subject of CEV capabilities I think there is some good evidence contained there that the crew size and other aspects of the CEV are not just arbitrary.

That leads me to more of Mr. Parkers points (accusations may be is a better word). Yes we do know that “it can be done with 3” but I also thought one of the criteria (unofficially at least) for the VSE was to not just repeat Apollo. Are you saying the CEV should have a crew of 3 simply because Apollo had a crew of 3? Isn’t that pretty arbitrary in itself? And as MrEarl stated above “If we’re just going to redo Apollo what’s the point?”

Mr. Parker is correct in stating there is no current launch site for the “stick”. As for the cost for constructing one compared to the construction a new EELV launch site I would guess that would pretty much be a wash. The big difference is (IMHO) that a new EELV launch pad would be for a 20 ton to LEO vehicle (DIVH) as compared to a 25-30 ton vehicle with the SRB stick. And as the documents I referenced above indicate there is good “non-arbitrary” reason to believe that the CEV launch vehicle will need to have a greater LEO capacity than 20 ton.

One final thought on a point raised above by Mr. Davenport on a Delta derivative HLV. It seems to me that it is largely the same people who say a Shuttle derived HLV would be too expensive that say a Delta derived HLV would be a good thing. It also seems to me that strapping (yes I know that is an oversimplification) 7 or more Delta CBC’s together is as difficult a proposition development expense wise as swapping a payload pod for the Orbiter or creating an inline craft using the ET, SSME, and SRB’s. And even at the very best cost estimate for a high production rate of CBCs of around $150 million each an HLV consisting of 7 CBCs would cost at least a billion dollars. And that doesn’t include any sort of upper stages.

Sure it is. Just look at the space station.