Showing posts with label rockets. Show all posts
Showing posts with label rockets. Show all posts

Friday, October 28

Kaboom

Those who have followed this blog know that I live amongst horses. This story doesn’t involve horses, but cows.

When I was about 18 years old, I had been working at a television station in Fresno for roughly a year. During one summer the station’s owner, a well-known cattle and cotton baron in the San Joaquin Valley, sent his grandson to the station to get some work experience. The kid was about my age, and we connected immediately. Since we were both unpredictable (even though I was dedicated to being responsible), we decided that the TV station’s elaborate chemistry set was way underutilized. I have no idea why a TV station had such a thing as a chemistry set, but that’s irrelevant. We read up on rockets, and decided to make one. We wrapped several layers of newspaper around a broomstick and secured it with masking tape. That made a sturdy and lightweight rocket body. We slipped the tube off and attached an aluminum foil nose cone.

The chemistry set provided all the necessary ingredients to make, essentially, gunpowder. We packed the paper tube with our mix, went out behind the studio to its manure pile (remember, the owner of the place had plenty of manure for gardening around the station), then carved a groove in the pile, placed a broken fluorescent light tube in the groove, put our rocket in the tube, and made a fuse out of a long string of crumpled newspaper.

It was early afternoon when we set a match to the fuse and were thrilled to see our rocket shoot out across the empty fields surrounding the TV station. It must have gone a thousand feet! Cool!

We made more rockets that afternoon and adjusted our manure-pile-fluorescent-tube groove to get more elevation. More successful launches only fed our desire to achieve more-spectacular results. As evening approached, we weren’t sure we would be able to see where our rockets were going, so I had the idea that we needed a tracer, something that would illuminate our rocket in flight when it was dark. Aha! Add some powdered magnesium to the mix. Magnesium burns hot and very bright. So our last rocket of the day had its usual gunpowder mix plus magnesium.

It was probably 7 or 8 o’clock when we launched it. Actually, it didn’t launch—it exploded! Turns out that magnesium powder burns really quick, and instead of the steady burn of our gunpowder mix, we had made a bomb. A really loud bomb. The manure pile, our faithful launch pad, was blown to oblivion and within an hour the sheriff was at the TV station, asking if we knew anything about the huge explosion that had the neighborhood in turmoil.

Denial was rampant. The on-duty director of programming pleaded ignorance of even hearing the explosion. The owner’s grandson had driven off in his expensive car, and I was only a low-level kid, obviously innocent.

A few days later the manure pile was replenished by the owner’s ranch hands.

Saturday, December 18

You’ve never seen it this way

Here all three engines are going full blast. See any smoke?

Our friend in Sweden, David, blogged about a friend who was with the Space Shuttle program for over 25 years. He included a link to a YouTube video that commemorates the program by showing the close-up technical details of a launch, taken with dozens of high-speed film cameras at the launch site. Imagine what it must feel like, perched atop a multi-million-pound-thrust rocket when it ignites and slams the whole assembly several feet off-kilter before it is freed from its eight explosive anchor bolts holding it to the launch pad. Every second the entire array is blowing off 23,000 pounds of mass until it reaches orbit eight minutes later at a speed of five miles per second.

The shuttle engines are fueled by hydrogen and oxygen so their exhaust is nice clean water vapor. The booster rockets are the real stinkers, spewing out the equivalent of the biggest tire fire in the biggest landfill imaginable. Oh well, at least they’re simple and reliable. And re-usable after they’re fished out of the ocean.

The video is over 45 minutes long. I sacrificed about a third of my daily Internet allotment via satellite, but it was well worth it! To see what I mean about the rocket assembly being tossed forward when the shuttle engines ignite, go to a place where you can see the entire assembly. When the shuttle engines start and before the boosters fire up, click on the progress button along the timeline and scrub it back and forth. That speeds up the action so you can see the amount of movement of the whole assembly. That must explain why the bottoms of the solid boosters are made of so many segments—they’re the only anchor to the earth right before takeoff and have to absorb that tremendous torque without breaking. Fascinating!

Right now I’m going to watch the whole thing again for the third time.