Friday, April 16, 2004

To Shuttle-C, or not to Shuttle-C. That is the question.

Jeffrey Bell, an adjunct professor of Planetology at the University of Hawai'i at Manoa has a new article up at Space Daily titled Shuttle-Derived Vehicle; Shuttle-Derived Disaster. Well, article is a bit of a misnomer. Rant is a more apt description. This man is dead-set against the development of the Shuttle-C (or Shuttle-Z if you're among The Case for Mars crowd) heavy-lift vehicles. Bell claims the Shuttle-C is too costly, too dangerous and too primitive to be used effectively.

Now Dr. Bell makes some valid points, don't get me wrong. But he also uses bait-and-switch tactics in his argument, nits and picks here and there and generally focuses only on those facts that support his case. He confuses the issue. At one point, he goes off on how a derivation of the Shuttle-C couldn't be made "man-rated":
Finally, the SRBs cannot be shut off in flight to allow the escape of a crew. SDV-2 could not be man-rated and we would have to develop a man-rated version of Delta 4 or Atlas 5 in addition to the SDV to carry crews up to LEO.

Well, yeah. That's kind of the whole point of the exercise: The Shuttle-C isn't supposed to be man-rated. It's supposed to be a big, dumb, heavy-lift booster. The basic design is inherently dangerous, which is why the existing shuttle fleet should be retired sooner, rather than later. Bell points out several promising alternatives, including kerosene-fueled boosters, and I agree that these would be preferable.

But he's ignoring reality. His claims of cost efficiency are as flimsy as those NASA made of the shuttle making several dozen flights a year. The development of a heavy-lift booster from scratch would eat up billions and take a decade, if not more. That's the way this beast works. Every Congressman would want his district to have a slice of the booster pie. What we'd end up with is a compromised launch vehicle beset by the same flaws he so gleefully points out on the shuttle system. And again, we'd be out of the space business for the better part of a decade.

Embracing the Shuttle-C design circumvents a lot of problems. The designs and studies have all been done. We know how to do it. If NASA ordered them built today, heavy-lift Shuttle-C could be on the launch pad inside of two years, which is probably sooner than we'll actually see a manned shuttle out there. Remember, we are technologically incapable of even building a Saturn V these days, as all the pertinent technical and manufacturing specs were destroyed or disposed of after Nixon killed off the moon program. We simply don't know how to build a heavy-lift booster these days, although we're quite good with light- and medium-lift rockets. More importantly, however, is the fact that the pipeline already exists for Shuttle-C manufacture and supply. There is significant financial and political pressure not to discontinue the manned shuttle program coming from current contractors, which could (will) make the job of retiring the shuttles and developing a replacement difficult at best. Maintaining their contracts for Shuttle-C launchers would keep many of them happy. It would keep many senators and representatives happy, too, which may be even more important.

A replacement for the shuttle as a manned spacecraft is imperative. A replacement for the shuttle as a heavy-lift booster is equally imperative. The idea that these two goals must be wedded into a single vehicle is foolish and wrong-headed. Splitting the systems into two separate vehicles makes the most sense, and avoids the conflicts inherent in the different purposes of those systems. The Shuttle-C is an interim step, a stopgap between what he have now that is terribly flawed, and the next generation booster, which may or may not arrive on the scene before 2015. The Shuttle-C isn't sexy, it's not hip and it's certainly not without serious drawbacks. It is, however, the only option we really have right now, and to my mind it's better to have a temporary, adequate solution than none at all.


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