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Just out of curiosity, is NASA hanging onto any of the shuttles just in case? Back when DIRECT was promoting an STS-based heavy launcher, they mentioned that there were enough fuel tanks and SRBs to do quite a number of flights - more than the shuttle has done. Could they just park the thing in a hangar somewhere and dust it off if the need arose?

Um, I was referring to Direct, the "SSTS without the space shuttle" design, not the Ares I "Stick". I was looking at the actual design for Direct's J-130 model right here. It's a stage 1.5 design with all engines ground lit and the boosters jettisoned during flight, just like the SSTS.
I do agree with your statement about the Ares I:

I worked on Ares and know what the design is. That thing was a gigantic piece of crap just waiting to fail. Badly. From the barely stable structural dynamics of a 400ft long pencil flying at mach 6, to the ugliest, most disaster prone separation sequence; that design was doomed to fail.

But that's not what I was talking about. :)

Also, the very first class you take in Aerospace Engineering teaches you exactly why SSTO (single stage to orbit) is not as cost-effective as multiple stages. So your argument that this design is better because it doesn't need a second stage is not a good one. The design might be simpler and easier to build, but it requires so much more fuel per launch that it isn't worth it.

As my argument about "single stage", I was referring to the fact that the design already gets 77mT to orbit with just a single (OK, 1.5 stage counting the SRB's) stage and that there was room for more growth, like a second stage, if you needed more lift and were willing to pay extra for it. Did I mention the option to use 5 segment SRB's? I could go on... It's just that the J-130 is the cheapest option for a new HLV, and it leverages all the work and research that went into the SSTS program, rather than throwing it away.

That's a good thing, in my opinion.

Per the official design from the Direct team (sorry for the pdf, that's what they have), it's 77,835kg to 30nmx100nm orbit for the regular NASA GR&A's. It's only down to 70mt if you arbitrarily factor in an additional 10% margin. Which doesn't account for their own internal 15% margin that isn't documented. I like engineers who give themselves leeway.

Short answer, yes, the 1.5 stage J-130 does 77mT to orbit per NASA rules.

You need to look at Direct Space Transportation System...

Direct 2.0 seems to be a safer path, perhaps Obama is actually on top of this...

I wonder if this alternative designed by NASA engineers in their spare time would require shock absorbers: http://www.launchcomplexmodels.com/Direct/index.htm

In medicine, it's called "allopathic", treating the symptoms. Doctors frequently do this because they're working from complaints and tests, not from a theoretical understanding of the systems. You can take aspirin for a headache. It'll probably work. You can't know without extensive testing whether that headache is due to a brain tumor (obSchwartzenneger: "It's NOT a tumah! It's NOT!").

A 4G vibration that's not felt by the astronauts but still occur in the vehicle could still rip the booster apart.

The DIRECT 2.0 alternative http://www.launchcomplexmodels.com/Direct/index.htm wouldn't have this problem. It uses mostly existing systems that have already been tested. (THIS is the real reuse of shuttle parts, not Ares). Yes, these have had their problems, but it was the engineers' idea, not something administratively mandated for them to design. I trust the engineers. When they ran things we had "failure is not an option" (Apollo 13). When management types took over we got "My God, Thiokol, what do you want me to do, wait until April to launch?" (SS Challenger). I'd sooner ride a non-man-rated SpaceX Falcon than anything devised by NASA management committee, much less something so devised then revised to eliminate the experience of the problem but not the problem. I'd at least like enough warning that something was going horribly wrong so I could scream.

The DIRECT v2.0 proposal has taken this "rebuttal" document and re-worked the architecture to baseline absolutely zero performance upgrades to the existing RS-68 engines as flown on Delta-IV. No re-optimized nozzle, no regenerative cooling, no fixes to the injector/combustion chamber. We are not even using the higher specification engine which NASA is still planning to use for Ares-V. DIRECT's Jupiter launchers do not require the additional 6% increase to existing RS-68 performance (nor the additional stresses) currently baselined for use on the Ares-V.

Drat. The proposal is in Pointless Document Format (PDF) and the animations are in penguin unfriendly 'Apple' format. What's wrong with HTML and uploading to Youtube?
Niggles aside, the FREE simulator sounds cool: http://www.launchcomplexmodels.com/Direct/orbiter.htm Must give that a go when I fire up Windows...
One idea that is missing from the proposal is a living module filled with fuel, to be abandoned somewhere in space, once the fuel/oxidiser has been used. This could be a way to build a space-hotel with extra rooms getting sent up with every launch.

Google dropped them?

You can try: http://www.google.com/search?q=direct+launcher

The first result is: http://www.launchcomplexmodels.com/Direct/what_is_direct.htm

Here are some pics. (Not mine, brought a non-digital cam.)