Friday, October 28, 2011

What Might Have Been, Part III

Forty years ago, when they were drawing up the plans for the Space Transportation System, the original plans called for a flight rate of about fifty times per year. About the most we ever managed on a consistent basis was six. Something doesn't quite add up, here. What went wrong?

Well, one thing that went wrong is that there was never enough traffic to justify a fifty-per-year sortie rate. And another thing that went wrong is that it takes about three to four months to turn an orbiter around for re-flight. Early turn-around estimates were wildly optimistic. Now, we could have achieved a fifty-per-year sortie rate. But we would have needed more orbiters. With each orbiter flying at most four times per year, you need at least fifteen orbiters to keep the flight rate up.

The additional expense of those orbiters probably isn't as much as you're thinking. A large part of a Shuttle's price tag came from the fact that we had to amortize the entire RDT&E budget over five units. Six, if you count Enterprise. Similarly, part of the reason that a Bugatti Veyron cost $2 million and a Toyota Camry costs $20 thousand is that only 200 Bugatti Veryons were ever built, and there are about 5 million Camrys out there. Once you build the factory and tooling, the marginal cost of each additional unit isn't astronomical; and if you build enough of them, you get better at it, and the efficiency begins to show in the unit cost.

Which still begs the question: you don't need such a high sortie rate, unless you're moving a lot of cargo upstairs. Which is what went wrong with my teaser from back in May. Without such cargo volume, why pursue the matter any further?

For a couple of reasons. First, it keeps my mind occupied when I'm on the treadmill. And second, counterfactual scenarios sometimes provide a glimpse into why things in the real world turned out the way they did. So, without further ado, we're going to board the bus for Crazytown. Don't worry, we've got return tickets.

First, we go back to the year 1969. The lynchpin of the Soviet answer to Project Apollo was Sergei Korolev's giant N-1 rocket. It was about as big, about as powerful, could lift about as much stuff into space ... and it had 30 engines in its first stage. As I've mentioned before, Korolev had spent the last ten or fifteen years in a pissing match with Chelomei and also with Glushko, who was the engine expert. Korolev had to use less powerful engines, which meant that he had to use a lot of them. The first flight of the N-1 was in February of 1969, and by "flight" I mean "explosion". Getting thirty engines to play nicely together is not exactly an easy feat.

Between 1969 and 1972, three more test flights took place. The N-1 program was not officially cancelled until 1974. The Soviet Union never did land a man on the moon, but it wasn't for lack of effort. At cancellation, two N-1 rockets were still ready for test flights.

Which brings up a very interesting question, and the springboard for our counterfactual exercise: Why, five years after they'd already lost the Moon Race, were they still working on a Moon rocket?

The most likely answer is simply inertia. Soviet programs tended not to be cancelled until someone with authority looked at it and said, "Why are we still doing this?" And sometimes not even then. Voskhod 3, for instance was never officially cancelled. The spacecraft stayed in a shed, kept ready, even as Soyuz 1 was being prepared for flight.

The more entertaining answer is that the Soviets were planning a propaganda coup, by the establishment of a permanent Lunar base. There were some plans drawn up to this effect, which is another reason why the plug wasn't pulled right away when Apollo 11 was successful. Part of the reason that the project was cancelled in 1974 is that none of the tests had been successful. But the truth is, each one got a little bit closer. The fifth test flight might well have done the trick, had there ever been one.

Now, in this scenario, it's 1976. Two successful test flights prove the design, and more rockets are built. While America celebrates its Bicentennial, giant Soviet rockets are delivering payloads to a rapidly-growing Soviet base on the Moon.

What I'm trying to sell here is a scenario where Reagan, as part of his defense build -up, buys a whole bunch of Shuttles, and plays catch-up in a Moonbase race. The problem with this scenario is that it requires everyone to go crazy, in the same way, all at once.

And, at the end of the day, I just can't buy it. No part of this is plausible.

The Soviet Union cancelled the N-1 in 1974 because at that point, it was a white elephant with no useful purpose. Even if it worked, it wasn't going to do anything especially useful for them. They had decided to focus on a long-duration spaceflight program, and score their propaganda points that way. It worked, after a fashion. To this day, all of the duration records are held by Russians, except only longest flight by a woman. The point is, they had found a way to make their case at an acceptable cost in time and materials.

And for us, as I've said several times, we've proven by trial and error that the American public is willing to spend about 0.5% to 1.0% of the Federal budget on NASA, to include all of its aeronautical research programs. There was never a political case to be made for a giant program involving a moonbase in the 1980s or 1990s. Which meant that the "design" sortie rate for the Shuttle was a moot point. Part of the reason it only flew four to six times a year is that there was only enough traffic to keep it busy four to six times a year. And even so, look at the other side of the record books: the people with six or seven missions to their credit? Only two Russians on that list. The Shuttle put more human beings into orbit than any other spacecraft. That's not an achievement to sneeze at.

As we turn the page on this fine project, and as we look back at the other things we might have done in its stead, I have to say that we probably did about as well as we could have. We lost fourteen fine people. But we gained an immeasurable amount of knowledge. Only time will tell if that was a good trade. All I know is, the people who made that sacrifice believed so.

I hope -- and I also believe -- they were right.

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