Monday, July 28, 2008

Divining the Future

The Emperor's pony-tailed study leader and his sidekick, the goateed master of power point, promised that ESAS was the most economical architecture that Americans could devise because it was just re-using existing shuttle hardware in exciting new ways. Unfortunately, as one other commentator has succinctly pointed out, the napkin engineered architecture has evolved away from its predecessor and could be considered, simply, "shuttle flavored."

Yet there is still one element that has retained more of its shuttle heritage than not, and therefore is most unlike what is to follow. ARES-1X. These differences accentuate the fact that ARES-1X is a contrived vehicle performing a contrived test. For all of you latecomers, here is what the "Buzz" is all about.

Claims of testing ARES-1 first stage flight dynamics, controllability, first and second stage separation, and first stage recovery should be viewed with twisted eyebrows and contorted expressions. Constructed with an "over-the-hill" (i.e., past its freshness date) four segment booster (SRB), the vehicle also carries a dummy fifth segment, an inert upper stage and an Orion boilerplate Crew Module topped by a Launch Abort System simulator. Much of the booster hardware was originally designed for lifting one side of a shuttle external tank, attached, and therefore stiffened, in two locations along its side.

Now, as any first semester theoretical and applied mechanics student can tell you, the free-body diagrams are a little different for ARES-1X and its future siblings. Without the stiffening effect of the ET, the SRB is free to twist and bend like a piece of spaghetti being pushed from below. So the Rubes (as in Goldbergs) at MSFC designed a Roll Control System for the top of the SRB to keep it flying straight as it goes uphill.

Unfortunately, the same folks who think a flight dynamics test of a four segment SRB with a different propellant, old-style grain design, and inert (that is to say, non-sloshing and stiff) upper pieces is a good idea also thought they could grab a bunch of used equipment (Atlas avionics software, Peacekeeper hardware, etc.), chewing gum, and duct tape (perhaps FEMA is helping the minions) and use it to demonstrate how something "like" ARES-1X might get off the ground after "the gap" has widened to its furthest extent.

And, like all of the shortcuts the Emperor's minions have taken to date, this approach, too, is soon to come back and bite them. The list of critical components going into ARES-1X that are either beyond shelf life or being put to work in an environment for which they were not intended is astounding. And the risks that are being accepted, because of schedule and budget pressures, are equally marvelous.

-Flight Termination System. Not qualified for ARES-1X environment.

-SRB fasteners. Negative margins of safety, not qualified for ARES-1X thrust oscillation environment.

-Pyro valves. Beyond shelf life, not qualified for ARES-1X environments.

-Aft Redundant Rate Gyro Unit. Not qualified for ARES-1X environments.

-Vehicle structure risks. First bending mode may be lower than desired, forcing control algorithm changes and additional testing.

-Modeling of joints not test verified for loads and dynamic analysis. Critical mode shapes and frequency for control may be incorrect.

In an effort to make Smoke and Fire and deceive the Congress and American Taxpayers into believing that progress is being made, the early ARES-1X test was conceived. But the deception is rickety. So, while ARES-1X may "look like a stick" it will not "walk like a stick." In fact, with each new review, it begins to look more like a divining rod that will shake itself directly towards the water.

4 comments:

kT said...

Thank you so much for inviting us to post more long and winding diatribes.

Do you have any idea when Visiongate is going to become a campaign issue?

Rob said...

I have never wished anything negative on NASA but if they keep following this path towards a broken stick I may start. Maybe it will take Ares-1X nose diving into the ocean before the administration wakes up to the reality of the situation. I just hope it clears the pad and doesn't damage any infrastructure.

Me said...

Ares 1-X will be the world's largest model rocket. It will do no more than a model rocket does. Some noise, flame, a smoke trail in the sky, a parachuting booster. The only thing missing is some fins. The real shame is that for the cost of this "test", dedicated EELV could be built. And when the cost of Ares 1 MLP and pad mods are included, an Orion capable EELV could be fielded.

Anonymous said...

Thank you for continuing your reports. I only wish you could post more often.