Rocketry is not inherently a dangerous hobby, although misuse or ignorance can cause severe personal injury and property damage. We use powerful motors and the rocket commonly fly hundreds of miles an hour (some high-power and amateur rockets even break the sound barrier). A 20lb rocket travelling at 500 mph is a force to be reckoned with! Even a rocket falling without a recovery system ("coming in ballistic") can do serious damage. I have seen a rocket drop through the roof of a motor home and trash a table inside.

Now that I've scared you, what are the things to be careful of? If you build a kit from a reputable manufacturer, following the instructions carefully, and use a pre-manufactured motor appropriate to the rocket, you should be safe. A common failure is a custom rocket design which is not stable. Unstable rockets will not fly straight and could go anywhere. Poorly designed or constructed rockets can break up in flight ("shred"). Before you start designing your own rockets, make sure you have experience with kits using the same motors you're planning to use in your own design and make sure you understand the principles of stability (see the Rocket Design section for the basics).

Materials and building techniques are also important. Model rocket materials (paper tubes, plastic or balsa fins and glue) are not appropriate for more powerful rockets. By the same token, high-power materials are not appropriate for model rockets because they weigh too much for model rocket engines to lift. Steel is not used for airframes or fins because it's too heavy for its strength. Large high-power and amateur rockets generally use composite materials like fiberglass. Despite what you saw in October Sky, steel is not a good material for building your rockets because a steel rocket tube falling from the sky makes a very dangerous projectile. Anyone hit by it will most likely be killed.

Please, please, please: carefully read the safety codes published by the National Association of Rocketry: the Model Rocket Safety Code and the High Power Safety Code.