Monday, February 23, 2015

What Could Have Been

Way back in the earliest days of the Apollo Program, they had no clue how to do the job they'd been handed. When President Kennedy laid down the gauntlet to put a man on the Moon by the end of the decade, America had a grand total of fifteen minutes and twenty-two seconds of spaceflight experience, and didn't even have a man-rated orbital rocket yet.

The most obvious, and in some ways the technically safest approach would be to build a ginormous rocket and lift the whole thing -- lander, earth-return stage, and capsule -- all in one heave. They called that approach Direct Ascent.

In the end, they decided against that approach. As it happened, if you split the earth-return capsule totally apart from the lander, you could save weight on both. That means you don't need such an enormous rocket, and the overall project cost is lower.

And besides which ... the Direct Ascent version of the Apollo 13 scenario is grim. No separate LM spacecraft means no lifeboat, and no lifeboat means three dead astronauts.

But we can still imagine what might have been. Seferino Rengel has used the Orbiter space simulator to visualize what it would have looked like.

Looks great ... but, on the whole, it's just as well we didn't go this route.

The great thing about Orbiter is that you can take a walking tour of designs that never were. You can appreciate the aesthetics, and sometimes come to a realization about why we didn't take that branch. Direct Ascent was just one example. Another example is the Lockheed Star Clipper. The pilot in me looks at that beautiful lifting body and drools ... but the engineer looks at that fuel tank layout and screams "Foam strikes ahoy!"

Another great thing about Orbiter is that we can imagine things that we could be doing, but for whatever reason aren't. Take the Grand Tour, for instance. When I was young, I assumed that this was a once-in-a-lifetime thing, that you'd never see such a fortuitous alignment again. Not so fast! For Jupiter and Saturn, at least, that alignment repeats every so often, and you can get one of Uranus or Neptune into the act as well. Such an alignment is available ... oh, right about now. Had we been more alert on the trigger, we could have something like Eris Explorer on deck and ready to go.

The mission plan is breathtaking in its vision, and optimism. The Eris encounter would be in 2051. I'll be 84 years old, making the bold and possibly unwarranted assumption that I last that long. When we go -- and we will, I'm sure of it -- the senior scientists and engineers on the project will simply have to accept that they won't survive to see the project come to fruition. They will have to hand it off to a new generation to bring it all together at the target. They'll have to assume that the organizations will still be viable entities throughout the entire duration of the mission. That the sponsor governments will stay the course, and provide funding for the whole course.

I find such optimism encouraging. When we plant a field that our sons and daughters will harvest, we make an investment in their future. And we can't invest in a future that we don't believe in.

National Engineers Week is February 22nd through the 28th. If you can read this, thank a teacher. If you can read this in English, thank a veteran. But if you can read this on a computer, thank an engineer.

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