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# The Banana Peel Bomb

Fast forward about 30 years. We lived in Maine. I was married and had 4 children. I guess I was having a mid-life revival of my childhood love of pyrotechnics. It was all the kid's fault, actually. I bought a few model rocket kits to fly with the kids. That was what rekindled the firebug in me. This quickly escalated into wanting to build bigger and more powerful rockets. The internet was just starting to be a great source for a lot of interesting knowledge and a way to buy mail-order chemicals to feed the curiosity.
My goal was to design and build my own rocket motors. I was no longer content to buy the feeble little black powder motors you could get for model rockets in the local hobby stores. I was a mighty engineer and I could do better. After considerable research, I decided to try a formula I found in the on-line literature. The problem was that the rocket motor design required quite a bit of specially fabricated metal parts. I had neither the skill nor the tools to do this kind of work, but I knew someone who did. Brother Bibber was a machinist by trade and was willing to help me achieve my goal by doing the machining. I gave him the drawings and waited. It was nearly 3 months before he had the time to make my parts, but finally, he delivered a shoe box of beautifully crafted rocket motor parts. The design consisted of a piece of chromium-molybdenum pipe with threads at both ends. The concept required cylindrical shaped castings of rocket fuel that were placed inside the pipe container and then the end pieces were screwed on to enclose the solid rocket fuel. It was not much different than those silly home-made bullets I made as a child. It was still basically a fancy pipe-bomb, just a lot bigger and a lot more expensive. However, I was still just as naïve to believe my newest incarnation would work perfectly the first time.
I thought my test plan was reasonable. I wanted to do a static test firing of the new motor design. I built a wooden test stand out of scraps of lumber. This stand was supposed to hold the motor in a stationary position while it was fired. This would allow me to demonstrate that the motor would actually develop enough thrust to cause a rocket to fly. After a successful static test, I would then use it to send a rocket into the sky.
On the fateful day of the static test, I set up the test stand in the driveway in front of the garage. I loaded the assembled motor into the test stand and installed an electric ignitor. I called the kids to come see the test and we all stood about 10 feet away from the test stand as I pushed the button to ignite the motor. It worked beautifully for about 10 milliseconds and then went kaboom with a bright flash of fire and smoke. My test stand, which was constructed of sturdy 4-by-4's, was blown into a cloud of tooth-pick sized splinters of wood. The motor itself was nowhere to be seen. I just disappeared into thin air. I finally found it a few days later when I spied it on top of the garage roof. After retrieving the motor from its perch on the roof, I realized how incredibly lucky we had been. The rocket motor looked like superman had opened it like a banana. One end of the motor casing had split open and the sides of the tube were bent back just like a half-eaten banana.
It was evident from the shape of the wreckage that the metal alloy had been able to burst open without splintering into deadly metal shrapnel that might have seriously injured me or one of my children. This is when it finally dawned on me that I was incredibly lucky and still had rather poor judgement when it came to assessing the risks of doing pyrotechnic experiments. Furthermore, my beautifully machined metal parts, for which I had waited anxiously for many months, had been totally destroyed in an instant. It put a serious damper on my enthusiasm to become an amateur rocket scientist.
This dramatic failure caused me to take a new direction in my pyrotechnic experimentation. I decided that rockets were too complicated. I would use the chemicals I had purchased to make fireworks instead. This kind of skill didn't require so many expensive tools and complicated parts. Most of the fireworks could be made with common cardboard tubes and glue. Thus, fate had sent me on a whole new kind of hobby pursuit. However, it didn't do much to lessen the likelihood that I would still experience epic failures. As you will soon see, my list of pyrotechnic failures was only just beginning.