April Madness

The Dallas Area Rocket Society was the next rocket group to host a competition in the central Texas area.  This launch was held a little bit east of Dallas, so Terri and I stayed with relatives and friends for the weekend.  It turned out we had tried to plan too many activities for one weekend, so we were both very tired by Sunday evening.

I did not have as much time to work on my contest rockets as I had hoped.  This resulted in my not participating in all of the events.  One of these events involves building a normal plastic model so it can fly like a rocket.  I had a lot of fun working on my model, but it is still sitting unfinished in my work area.  I do have a large head start for this event next year!

The other event I did not attempt was flying an egg as high as possible on a D motor.  I was able to finish this rocket for the contest, but I did not have enough time to fly it.  I had planned to spend time with some old friends on Saturday night, so I left before the altitude tracking was available.  I overslept on Sunday morning and missed the tracking on that day too.

My preparation for the streamer duration event really paid off.  I spent quite a while building and testing rockets and streamers in the months preceding this contest.  I built the rocket body buy forming a tube with drafting vellum.  This is a thin type of paper resulting in the rocket not weighing very much.

My streamer was constructed from 0.25mm aluminized Mylar.  This sounds rather fancy, but it was really a strip of wrapping paper I bought at a dollar store.

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This material can be folded into a very small space, which allows me to use a large streamer in a tiny rocket.  The object of this event is to keep the rocket in the air as long as possible.  A big streamer in a light rocket can float for a while.  My first flight landed two fields away.  The Mylar also tries to go back to it's original shape, so it extends to full length quickly after being ejected.  The aluminum coating is easy to see from a distance which helps the timers to follow the rocket if it flies a long distance, as mine did.

I was the only person in my age bracket to successfully complete two flights.  The times for both flights are added together for the final score.  My flights lasted for 29 and 26 seconds for a total of 55 seconds.  The person in second place only completed one flight for 16 seconds.  This was by far my best event.

For parachute duration, I used the same design as with the streamers.  Both events used the same type of motor, so I figured it would not be too difficult.  My first flight only lasted 14 seconds because the parachute stayed bunched up in a ball.  While getting ready for a second flight, I could not fit the parachute into the rocket.  Had I practiced for this as much as I did with the streamer rockets, I would not have had these problems.

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The final event in the competition was another duration event using a helicopter recovery device.  I spent a lot of time researching and building a rocket for this event, but I was not able to test my design before the contest.  This made me a little nervous.

The first picture shows how the rocket looks when it is launched.  The helicopter blades are held down along the body until the motor's ejection charge goes off.  My blades also fold in half lengthwise.  This creates a very thin rocket which should help it to fly higher during the rocket's boost.

After the ejection charge, small rubber bands pull the blades out to their full extension.  I have left one blade down so you can see how they fold lengthwise.  There are small pieces of rubber glued to the top of the blades which unfolds them.  The engine compartment is connected to the helicopter section with a piece of Kevlar cord.  This allows the blades to spin faster and helps to keep the rocket stable while descending.

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It turns out I was nervous for nothing.  Both of my flights with this rocket worked perfectly.  It obtained times of 17 and 21 seconds which was enough to earn me second place in this event.  Since this was the first time I had flown the rocket, I observed several ways to improve the design for better performance.  I am looking forward to trying them out in the future.

At the end of the contest I had enough points to place forth.  I am very happy with this finish considering I did not fly in two events.  I had a lot of fun competing in these new event and learned quite a lot.  Meeting the people in the Dallas club was also a great experience.  Next time I will plan a second trip to spend with my friends, but I still had an absolutely wonderful time.