Rocketry 101

Basic Model Rocketry

The hobby of Model Rocketry has been around for almost a half century. In all of that time it has proven to be one of the safest, affordable, educational and rewarding hobbies around. No matter your age, gender, background or abilities, anyone and everyone can participate in this hobby to whatever degree they desire. I have been enjoying the hobby since 1968 and there was a time that the sum total of my knowledge of rocketry and flying would fit inside these brackets { } but I was fortunate enough to have my dad and a couple of friends help me get started.

Today there is a wealth of information and many organizations and clubs to help those interested in learning about rocketry. You may find it interesting that you do not need to know every law of science and aerodynamics in great detail to enjoy flying rockets. If you can read this brief article and follow simple instructions, all you need is a few minutes and a little basic knowledge to get started. From that point you can take hobby rocketry as far as you want to go. More than one astronaut took the first step toward a career at NASA when they launched their first model rocket.

Getting Started - Low Power Rockets

Many people struggle with the question of how old is old enough to begin flying model rockets. That of course depends on the individual but it has been my personal observation that most people are ready about the time they reach junior high. With adult supervision some children may be ready even sooner.

The quickest and easiest way to get started with model rocketry is to purchase a starter kit from Estes or similar manufacturer. From the rocket to the pad, a starter set will have everything you need to hit the field in a hurry. It will not take long for you to realize that even with low power there are many types of rockets and skill levels. As you progress from one level to the next your understanding and your fleet will grow. Here is a quick look at what you should already know as you go to the field for your first flight.

Model Rocket Components / Assembly

Whether it is a completely assembled RTF kit (ready to fly) scratch built (built from your choice of random parts) or kit bashed (combining different kits) all model rockets consist of the same basic components. A nose cone, body tube, fins, engine mount, launch lug, shock cord and recovery system. They all require an engine to get them in the air and wadding or some type of fire retardant or mechanism to protect the recovery system from the hot ejection gases.

The first thing you need to do is decide on the kind of rocket you would like to use to begin enjoying your new hobby. The most basic rockets come pre-assembled and they are referred to as "ready to fly" or RTF. All you need to do is install the engine and igniter and it is ready to fly. Most low power model rockets come in kit form from a manufacturer such as Estes, Quest, Custom, etc. and in various skill levels from beginner to master modeler. Commercial kits will have the skill level listed on the package or in the manufacturer's catalog. The parts are mostly made from balsa, heavy duty paper and plastic. Step by step instructions will guide you through assembly using various types of glue such as Elmer's white or yellow wood glue. Cyanoacrylate or Super Glue, is also a popular adhesive but be careful to make sure you know which rocket parts are compatible with CA, as it can ruin some types of rubber, plastic and styrofoam.

Depending on the age of the individual, for first time flyers I recommend a starter set with a RTF or skill level 1 kit and progress to more advanced designs as experience, abilities and desire increases. It does not take much time or money to know if hobby rocketry is a real interest or a passing fancy. If the individual decides the hobby is for them, it will not take very much time or money to advance to the higher skill levels of low power but do the smart thing and learn to walk before you try to run.

Model Rocket Engines / Launch Pad / Ignition System

Single use disposable black powder engines are used to lift the rocket into the air. Engines consist of the casing, nozzle, propellant, delay element, ejection charge and end cap. Booster engines consist of a casing, nozzle and propellant only. Engines come in many power levels and delays with low power rocketry considered to be 1/4 A - D engines. They are sold in small packs of 3 each while a few sizes come in bulk packs of 24. All engines come with instructions and igniters. Engines have an easy to read number code that will tell you the total impulse, average thrust and delay time in seconds. For example, an A8-3 breaks down as: A = total newton seconds, 8 = average thrust, 3 = ejection delay time in seconds. Power ratings also increase as the letter system progresses. B engines have twice the impulse of an A engine, C engines have twice the impulse of a B engine etc. The color code is also important: Green- single stage, Purple - upper stage, Red - booster, Black - plugged for special applications.

Hobby rockets must use a launch pad for safe liftoff. Launch pads have a strong wide base for stability, a blast plate to deflect the flames and hot particles of the engines away from the ground and a steel rod for guidance until the rocket achieves enough speed for the fins to take over.

All model rocket ignition systems are electrical. Simple ignition systems consist of a keyed controller, a battery and a set of leads and clips. The control key prevents premature or accidental launch and the light shows continuity. When the rocket is prepped, on the pad and ready to launch the key is inserted. If all is in order the continuity light glows and you are ready to fly.

Model Rocket Flight Sequence / Recovery

Count it down, push the launch button and watch it go! Fire and smoke and noise! Ignition is acquired electrically from a battery, the igniter glows, the engine ignites and the rocket rapidly accelerates upward until the propellant is exhausted. It then goes through the coast phase where it reaches peak altitude and the ejection deploys the recovery system. There are several types of recovery for model rockets. When a rocket is too heavy to safely tumble down or use a streamer, a parachute is most often employed but some rockets are made to glide back or deploy rotating blades like a helicopter.

Mid Power Rockets

The understanding and flight experience you have gained from low power rocketry will help to prepare you for the next step, mid power. Larger, heavier and more powerful than basic model rockets, mid power rockets use composite engines in the E, F, and G range. There are many commercial kits available for mid power or you can build your own design from scratch. Any rocket weighing over 1 pound or that uses 4 ounces or more of propellant will require you to notify the Federal Aviation Administration, before you fly! While built and flown using many of the same techniques as low power rockets, mid power rockets fly much higher and can carry heavier payloads like small video cameras. Some use an altimeter for electronic deployment.

Of course, flying larger rockets requires a larger investment. Kits, parts and engines will cost a little more. As your fleet grows in size and power your launch system and equipment will need to grow as well. The size of your investment will depend on how far you want to take your experience.

National Association of Rocketry / NAR Safety Code

The NAR began in 1957 and has grown to be the oldest and largest sport rocketry organization in the world. The NAR has national launches, events and competitions and many local clubs throughout the U.S. not to mention a slick monthly magazine, all with the purpose of promoting the hobby of rocketry in a safe and fun way that everyone can enjoy. To see all the NAR has to offer visit the website at: https://www.nar.org/

Model rocketry has a long and excellent safety record. All responsible model rocket hobbyists fly by the rules of the NAR or a similar safety code. The code is a set of 11 rules and guidelines that are included with every kit and pack of engines. When followed properly the code serves to protect the hobbyist and the public. Learn the code, build and fly by it's rules!

Where to Fly?

All the knowledge and equipment in the world is useless unless you have a good place to fly. Since most people do not have a large pasture for a backyard, many people begin flying at a local school or park but be sure to get permission from the proper authority before you take to the skies. It might be helpful to get aquatinted with your local fire codes as well. If possible locate and visit the nearest NAR club. They will have a good field, tons of information about flying and welcome you with open arms. It is always more fun flying with a group than by yourself.

Resources for expanding your knowledge of rocketry are available through several types of media. A good place to start is your local public library. There you will find books, magazines and tapes on flight, aerodynamics, rockets and space. Find a copy of G. Harry Stine's Handbook of Model Rocketry and absorb it. The internet is saturated with interesting websites about rockets and related topics.

Once you've decide to enjoy the hobby of rocketry you will need to find a place to purchase your kits, engines and supplies. There is no better place than BRS Hobbies to get started. BRS carries everything you will need to get started and keep you supplied.

Rocketry is a fun, safe and educational hobby the entire family can enjoy. Why not get started today?

by Randy DeArman Vernarockets.com