Throwing stuff at the internet to see what sticks
Thursday, March 31, 2011 The Right Stuff
Dave and Tara always seem to know exactly what to send M. Edium for Christmas, and this year was no exception. Aware of his interest in rockets and building stuff, and in our interest in giving him educational toys, they sent him a rocket to build. You know, just like in The Astronaut Farmer only smaller.
We had plenty of fun putting it together, but this week we got the opportunity to have plenty of fun trying it out. Now, none of what follows should be construed in any way as Dave and Tara's fault. It's my kid's.
1. On the day M. Edium decreed for our maiden flight, he had lost the three stabilizer fins. As you can see from the picture, these are flashy, sci-fi-looking pointy things made of foil-covered balsa wood. You'd think they'd be hard to lose, but he managed. I, in turn, managed by cutting some new fins out of a cardboard box. They weren't precision, or anything, and one of them even had a hole through it, but I hoped they would just keep the thing from zooming around the park like an untied balloon until it clocked someone on the bridge of the nose.
2. While carrying the rocket to the park, M. Edium tripped and fell over nothing at all, landing on the rocket. The fuselage was undamaged, but now at least two of the already-imperfect fins waggled limply. This proved to be an even bigger problem when we got to the launch site and discovered that the fins are not only aerodynamic, but structural. They're supposed to support the whole weight of the rocket before launch. In this condition they couldn't support an argument.
3. It's a chemical rocket, in the sense that it runs on vinegar and baking soda. You pour the vinegar into the "fuel tank" (essentially a plastic bottle that takes up most of the fuselage), put the baking soda into a plastic tube that fits into the fuel tank, give the whole rocket a firm shake, set it down, and stand back. It was getting close to bedtime, so I'd brought enough fuel for exactly one launch. After we got to the park, we upended the rocket and carefully poured the vinegar into the "nozzle" at the base, which took a few minutes because we were carrying it in a sport bottle (and remind me to rinse that out before Trash's next karate class). Once it was all in the tank, M. Edium immediately did what came naturally, which was to turn the rocket upright again. And since we hadn't closed the fuel tank, ¾ of the vinegar splashed out onto the snow.
Obviously NASA would have postponed this launch several dozen times by now, what with missing stabilizer fins, jury-rigged replacements, no way to keep the rocket pointing upright, and a quarter of the required fuel. But what the hell, we were here, right? They launched the Challenger, after all.
While M. Edium retreated to a safe distance (actually several safe distances – dude was half a city block away), I stuck the tube of baking soda into the fuel tank, gave the whole rocket a shake, and tried to figure out how I was going to keep it upright for the five to eight seconds until it went off.
Again, a minor rocketry/chemistry lesson. As the baking soda and vinegar mix, it foams up, as anyone who has ever made a model volcano (including M. Edium) knows. This is carbon dioxide forming. This gas is trapped inside the fuel tank by a rubber stopper, which pops off when the pressure becomes too great, sending the rocket soaring up to three hundred feet above out neighborhood. In theory. If the stopper's in too tight, the instructions warn, it won't pop. If it's too loose, it won't build sufficient pressure before it pops. The instructions don't really tell you what to expect if you're only using a quarter of the recommended vinegar, but I can guess the answer is "not great things."
So I tried sort of balancing the primed rocket between its one good stabilizer fin and the fingertips of one hand, but it tipped over. And the stopper popped, and the rocket skated about twenty feet across the snow. But at least we saw a good demonstration of the driving concept, right? Which led to the fourth problem:
4. "I wasn't looking," M. Edium said.
Philip Kaufman's The Right Stuff is a great movie about the triumph of innovation and the American spirit, but it's also about the triumph of persistence. In most of the film, we're battling to catch up to the Russians in the Space Race, because of course back then – and even later, when the movie was made – we only knew about the Soviet successes and not the horrifying failures that came to light decades later. In the sequence I'm thinking of, rocket after American rocket explodes on the launch pad, sinks back into its own exhaust, or just pops off a pathetic little nose cone as though it's being piloted by Astronaut Gonzo.
Of course these were seen as failures, especially when they were the culmination of those dramatic countdowns they used to do. But NASA learned from every failure, and figured out how to fix the problems, and now here it is 2011 and we're all shuttling back and forth between our vacation homes on Ganymede and Europa.
The point is that NASA kept trying, and so will M. Edium and I. On our own, much smaller scale, if it's true that you learn more from your failures than your mistakes, this has turned out to be an even more educational toy than Tara and Dave realized. Having four launches' worth of failures in one attempt will do that. posted by M. Giant 10:02 PM 0 comments