A model rocket is a small rocket capable of being launched by anybody, to generally low altitudes (usually to around 100-500 m (300-1500 ft) for a 30 g (1 oz.) model) and recovered by a variety of means.
According to the National Association of Rocketry, (NAR) Safety Code, model rockets are constructed of paper, wood, plastic and other lightweight materials. The code also provides guidelines for motor use, launch site selection, launch methods, launcher placement, recovery system design and deployment and more. Since the early 1960s, a copy of the Model Rocket Safety Code has been provided with most model rocket kits and motors. Despite its inherent association with extremely flammable substances and objects with a pointed tip traveling at high speeds, model rocketry historically has proven to be a very safe hobby and has been credited as the most significant source of inspiration for children who eventually become scientists and engineers.
While there were many small rockets produced over the years for research and experimentation, the first modern model rocket, and more importantly, the model rocket engine, was designed in 1954 by Orville Carlisle, a licensed pyrotechnics expert, and his brother Robert, a model airplane enthusiast. They originally designed the engine and rocket for Robert to use in lectures on the principles of rocket powered flight. But then Orville read articles written in Popular Mechanics by G. Harry Stine about the safety problems associated with young people trying to make their own rocket engines. With the launch of Sputnik, many young people were trying to build their own rocket engines, often with tragic results. Some of these attempts were dramatized in the fact-based movie October Sky. The Carlisles realized their engine design could be marketed and provide a safe outlet for a new hobby. They sent samples to Mr. Stine in January, 1957. Stine, a range safety officer at White Sands Missile Range, built and flew the models, and then devised a safety handbook for the activity based on his experience at the range.
The National Association of Rocketry (NAR) was founded in 1957 to help promote not only the hobby, but to promote the safety of the activities related to model rocketry.
Most small model rocket motors are single-use engines, with cardboard bodies and lightweight molded ceramic nozzles, ranging in impulse class from fractional A to E. Model rockets generally use commercially-manufactured black powder motors. These motors are tested and certified by the National Association of Rocketry, the Tripoli Rocketry Association or the Canadian Association of Rocketry. Blackpowder motors come in impulse ranges from 1/8A to E, although a few F blackpowders motors have been made.
Model rocket motor classification: Motors for model rockets and high powered rockets are classified by total impulse into a set of letter-designated ranges, from A (the smallest, though 1/2, 1/4, and 1/8-A motors are also available), up to O as the largest. A is from 1.26 newton-seconds to 2.5 N·s, and each class is then double the total impulse of the preceding class, with B being 2.51 to 5.00 N·s.
Model and high-power rockets are designed to be safely recovered and flown repeatedly. The most common recovery methods are parachute and streamer. The parachute is usually blown out when the engine's recoil creates pressure and pops off the nose cone. The parachute is attached to the nose cone, making it pull the parachute out and make a soft landing.
Cameras and video cameras can be launched on model rockets to take photographs in-flight. Model rockets equipped with the Astrocam, Snapshot film camera or the Oracle or newer Astrovision digital cameras (all produced by Estes), or with homebuilt equivalents, can be used to take aerial photographs.
As with low power model rockets, high power rockets are also constructed from lightweight materials. Unlike model rockets, high power rockets often require stronger materials such as fiberglass, composite materials, and aluminum to withstand the higher stresses during flights which often exceed Mach 1 (340 m/s) and over 3,000 m (10,000 ft.) altitude.
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Amateur rocketry, sometimes known as amateur experimental rocketry or experimental rocketry is a hobby in which participants experiment with fuels and make their own rocket motors, launching a wide variety of types and sizes of rockets. Amateur rocketeers have been responsible for significant research into hybrid rocket motors, and have built and flown a variety of solid, liquid, and hybrid propellant motors.
A hybrid rocket is a rocket with a rocket engine which uses propellants in two different states of matter - one solid and the other either gas or liquid. The Hybrid rocket concept can be traced back at least 75 years.
A water rocket is a type of model rocket using water as its reaction mass. The pressure vessel—the engine of the rocket—is usually a used plastic soft drink bottle. The water is forced out by a pressurized gas, typically compressed air.
Model aircraft are flying or non-flying models of existing or imaginary aircraft, often scaled down versions of full size planes, using materials such as polystyrene, balsa wood, foam and fiberglass. Designs range from simple glider aircraft, to accurate scale models, some of which can be very large.
Model Rocketry was an American hobbyist magazine published from October 1968 to February 1972. The Editor and Publisher was George Flynn and the Managing Editor was Gordon Mandell. The magazine was owned by the editorial staff and the paid circulation reached 15,000 by 1970.
A sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The origin of the term comes from nautical vocabulary, it refers to to sound, which means to throw a weighted line off of a ship to gauge the water's depth. It is intended here as taking a measurement.
High-power rocketry is a hobby similar to model rocketry, with the major difference being that higher impulse range motors are used. The National Fire Protection Association (NFPA) definition of a high-power rocket is one which has a total weight of more than 1500 grams and contains a motor or motors containing more than 62.5 grams of propellant or rated at more than 160 Newton-seconds of total impulse.
Estes Industries (AKA Estes-Cox Corporation) is a company based in Penrose, Colorado, USA that designs and builds model rocket and model aircraft engines and kits. They were the best known model rocket company during the "golden age of rocketry" in the 1970s and early 1980s, competing primarily with Centuri Engineering and a host of smaller firms like Canaroc and Flight Systems, Inc. In the 1990s the hobby had almost disappeared, and Estes bought Centuri, folding their product lines together. Throughout the 1990s Estes owned North Coast Rocketry which served as their Mid-High Power Model Rocketry division, which was discontinued in 2000. Today, in addition to producing model rocket engines, Estes offers model rocket kits for various skill levels of modelers, as well as remote control airplanes.
Oracle is the name of a model rocket with built-in digital camera, manufactured by Estes Industries, for aerial photography. In contrast to the camera rocket Astrocam, the Oracle allows the making of a complete film of a rocket flight. The Oracle is best flown with a D12 engine (see Estes number coding), but can be flown with C11 engines.
A solid rocket or a solid-fuel rocket is a rocket with a motor that uses solid propellants (fuel/oxidizer). The earliest rockets were solid-fueled and powered by gunpowder; they were used by the Chinese, Mongols and Arabs in warfare as early as the 13th century. All rockets used some form of solid or powdered propellant up until the 20th century, when liquid rockets and hybrid rockets offered more efficient and controllable alternatives. Solid rockets are still used today in model rockets and on larger applications for their simplicity and reliability. Since solid fuel rockets can remain in storage for long periods—and then reliably launch on short notice—they have been frequently used in military applications such as missiles. Solid fuel rockets are unusual as primary propulsion in modern space exploration, but are commonly used as booster rockets.
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