High Power Rocketry

I started building model rockets when I was in 3rd grade. The first rocket I ever built was an Estes Wizard (with the old paint scheme, not the new ugly one). With my cousins, I built and launched model rockets continuously all through elementary school until I went off to high school. I took a bit of a break through college but about 15 years ago or so I started back again. About 10 years ago, I started going to launches at a “high power rocketry” field near Whitakers, NC. The people there at Whitakers were very friendly and several years later I started building bigger rockets than the ones I built as a kid. However, in order to use larger rocket engines, you have to go through a certification process.

Rocket engines are classified by letters. A basic engine is classified as an “A” engine and from there each subsequent letter indicates that the motor has twice the power of the previous letter. Basic model rockets when I was growing up used engines in the 1/2A to D range. When I got back into rocketry after college that had been raised to an E engine, but not much beyond that. Estes engines are made of black powder and you can’t get that much more power out of them without making them a lot bigger. Above E engines generally use Ammonium Perchlorate Composite Propellant (or APCP), which is the same propellant used by the Space Shuttle’s solid rocket boosters. When you get to H motors, though, you have to go through a certification process in order to be able to buy and fly these higher power motors. There are 3 levels to this certification: Level 1 includes H & I motors, Level 2 includes J, K & L motors and Level 3 includes M and above motors.

About a year and a half ago I managed to successfully get my Level 1 certification at a launch in Richmond, VA. My rocket actually ended up landing in a tree (!!!) but the Richmond club members got it down within a few days and according to the rules that was good enough for me to certify.

This past summer, my entire family traveled to Potter, NY for LDRS28 (LDRS stands for Large, Dangerous, Rocket Ships) and got to see a lot of really cool high power rockets.

All this past year, I’ve been working on building a rocket that would let me get my level 2 certification. With level 1 certification, you simply have to build a rocket and launch it with an H or I engine and get it back intact. With level 2, you have a test, which I took in November and aced, and you have to launch and retrieve intact a rocket with a J, K, or L engine. With my rocket, though, since the altitude for a rocket on a J motor would be much higher, I decided to go for what’s called “dual deployment”. With dual deployment, you have an altimeter in the rocket that handles ejecting the parachutes. At apogee, it ejects a small parachute that simply keeps the rocket stable as it falls to ground. Then, once the rocket is closer to ground, say 500-1000 feet, the altimeter ejects the main parachute which is large enough to land the rocket very gently. The advantage of this is that you don’t have to walk as far as you would if you ejected the main parachute at apogee.

I finished building my rocket this past summer and this past fall I tested it out with lower power engines. I wanted to do my certification flight in December, but weather and other problems prevented that from happening. This past weekend, though, I finally went out to the high power rocket field near Bayboro, NC and launched my level 2 rocket on an Aerotech J350 motor. The weather wasn’t perfect. There were fairly low clouds and haze and the rocket disappeared fairly quickly. Luckily, though, I had the forethought to borrow a friends radio transmitter and put that into the rocket. We pulled out the receiver and after a while determined that the rocket was now on the ground. I then looked over in the direction of where the rocket should be and saw my 36 inch, hunter orange parachute on the ground and flapping in the wind! Yay! After walking quite a ways and having a local farmer help out with his four-wheeler, I managed to retrieve the rocket intact and officially get my certification.

So, now I’m level 2 certified for high power rocketry. Will I go on to get my level 3 certification? At the moment, I’m not sure. I can do quite a lot with level 2 so I may just stay here for a while. I think eventually I will want to get my level 3 certification, but I’m in no hurry.

Anyway, here’s a video of the launch. You can hear how windy it was (between 10-20 mph winds!) and see how cloudy it was and how quickly the rocket disappears. But, it should give you a good enough view of how the launch went. Once you’re done with that, you can see a few other pictures I took that day.

Posted via web from Clubjuggler