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---
title: 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.
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