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Rocketry Overview
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Types of RocketryThere are basically three types of amateur rocketry today, model rocketry, high power or large scale rocketry, and experimental rocketry. Terminology is still not totally consistent and agreed upon by everyone. Each has its own group of people involved in it and each draws people from a different interest. Although participants may be involved in more than one, it is more often that involvement in one leads to another as an evolution and as a more challenging aspect. Model RocketryModel rocketry is the most well known and the most commercialized of the three. Most people have seen Estes model rocket kits and rocket motors that power them. Estes is the most widely known model rocket company but there are others and in the past others have come and gone. A person can build their own rockets from the body tubes, nose cones, engine tubes, etc. that Estes and others have available but the majority of people build kits. Most people probably started with model rocketry before moving into the other two areas and young people involved in rocketry are almost exclusively involved in model rocketry because of the complexity of the other areas. Technically, model rocketry is restricted to the following limits:
In addition you must notify the nearest FAA control tower of your activities when launching model rockets weighing between 454 and 1,500 grams, or whose total propellant mass is in the range between 113 and 125 grams. This is so they can route airplanes around your rockets. Normally, model rocketry is considered to range from 1/4 A to D motors while E through G are often referred to as: Mid Power Rocketry. Another distinguishing feature of model rocketry is that it generally uses cardboard, plastic, balsa, and other low weight materials in the rockets for safety reasons (as well as low cost).
"Large Scale" and "High Power" go together. Larger rockets need larger engines in order to fly and larger engines will only fit in larger rockets. High power rocketry starts where model rocketry leaves off. They fly "H" engines and larger. Commercial engines are available up to "O" in size. Since each letter doubles the size of the previous letter designation, an "O" motor is 4096 times larger than a "C" engine that is most commonly used in model rocketry. The "O" engine price approaches $1000 and could lift a rocket to five miles. As engines and rockets get larger, there are more stresses put on the rocket and so more advanced building techniques and materials must be used. Recovery systems also get more complex. Model rocket engines use paper casings, clay nozzles, and black powder for propellant. Larger engines must use stronger materials for the casing and nozzles, typically metal, and use higher energy composite propellants. Large engines are controlled, as is the flying of high power rockets. Two organizations, NAR (National Association of Rocketry) and Tripoli have chapters around the United States and abroad, hold launches, and provide control of the sport through certifications. A person must go through qualifications including building, preparing, launching smaller rockets and take a written test to obtain certifications which then entitle them to purchase engines and fly rockets with those engines. Three levels of certification are used in both organizations: level 1 is for H and I motors, level 2 for J, K and L motors, and level 3 is for M, N and O motors. Experimental Rocketry Experimental Rocketry generally is the term used for rockets whose motors are homemade and for rockets and motors that do not fall into the other categories such as those that use metal in the airframes, larger than "O" engines, etc. Amateur Rocketry and Amateur Experimental Rocketry (AER) are also sometimes used for this class of rocketry. AER is one of the major parts of this web site (For now THE major part that I am concentrating on).
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