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Rocket building and flying is a popular activity for schools, scouts, and children’s organizations such as 4-H. Lessons learned from rocket building include how to plan, start and finish a project, organization of tools and parts, model building skills, and how to use tools. Rocketry can also introduce kids to the exciting world of space technology. Rockets are also lots of fun, which is the main reason for building and flying them. A good first rocket for individuals or groups is the Gnome from Estes. It is an E2X kit which needs no painting or complex gluing. It is available in economical bulk packs for group building. A minimum of tools are needed for rocket building and include: Scissors Hobby knife Pencil Plastic Cement - model glue Masking Tape The first step in building the rocket is to lay all the parts out on the work surface in front of you, identify them from the plans and make sure they are all there. Using the plan as a guide, organize the parts in the order in which you will be using them.
Glue the nose cone assembly together Mark body tube for fins using a door frame as a guide Install the fin unit on the body tube - use the line you drew in the last step to properly align the unit Install engine hook. The Gnome uses a streamer recovery system to slow down it’s descent The shock cord/streamer is installed in the next step - cord glued inside the body tube - the shock cord is an elastic cord The streamer is taped to the shock cord Streamer is rolled up and pushed into body tube - install nose cone. Decal the rocket - its ready to fly! The Gnome takes about an hour to build and will fly to 200 feet. It can be launched from a baseball field with a 1/2A3-4T engine. Launch using instruction from an earlier column. After building this one, you are ready to build and fly many other of the many kinds of rockets available in the hobby shop. An earlier column outlined many of these exciting and colorful rockets. Back To History of the Rocket © 2012 Hobby Hobnob Friday, September 21, 2012Model Rocket Parts And What They DoBuilding and flying model rockets is a fun and exciting hobby. Many kid’s organizations like 4-H and Scouts have rocketry as part of their programs. Many schools build rockets as class projects to learn about space and rocketry. Rocketry is easy to learn. The model rocket parts are pretty basic and consist of the body tube, nose cone, engine mount, launch lug, parachute, fins, and shroud line. The body tube makes up the main body of the rocket. It is made of a lightweight material, like cardboard, is hollow. In flight, it contains the parachute, recovery wadding, engine. The nose cone attaches to the body tube at the apex of the rocket. It helps lower air resistance to the rockets flight. It comes off with the ejection charge to allow the recovery system to deploy. The engine mount is installed at the bottom of the rocket, and holds the rocket engine in place during the flight. The launch lug attaches to the side of the body tube. It holds the rocket securely to the launch rod on the launch pad while launch arrangements are being made. The parachute is packed inside the body tube before flight, and is attached to the body tube with the shroud line. The parachute is deployed when the ejection charge is fired, bringing the rocket safely back to earth. The fins are attached to the bottom of the body tube. They give the rocket stability during flight. Rockets may be flown on as small as a 1/4 acre. Field size is determined by the size of the rocket and size of the engine used. The smallest engines - 1/2A - will fly a rocket up to 200 feet in altitude, and will require an altitude of about fifty feet by fifty feet. A engines will achieve about 400 foot altitude and need about 100 feet by 100 feet area. B engines will fly approximately 800 feet high and need about 200 feet on each side - this is about an acre. C engines will achieve about 1600 feet in altitude and need about 400 feet on each side. This is about 2 acres. D engines push a rocket up to about 1800 feet and need about 500 feet on each side. The rocket engine casing is composed of paper and clay materials, and are pre-loaded with non-toxic, bio-degradable materials. The engine is used once, and discarded. The rocket engine’s attributes are communicated by a simple to understand code stamped on its side, and on the package. A8-3 would be an example of this code. The A designates the total thrust of the engine expressed in Newtonian seconds. Their are four letter grades - A, B, C, and D. Each letter grade is twice as powerful as the one preceding it. The first number is the average thrust of the engine expressed in Newton’s. The last number in the code tells you number of seconds from engine shutdown until the ejection charge fires. The longer this interval is, the higher the rocket will go, as it will drift upward until the parachute deploys. The igniter is the next thing we well talk about. It is, quite simply, a wire made from an electrically resistant material. When electricity from the launch controller is applied, the igniter heats up, igniting the propellant in the rocket engine. The igniter installs in the dimple like depression in the bottom of the rocket engine. Be careful with the igniter, as it is quite brittle and easily broken. Make sure the igniter is firmly seated and making good contact with the propellant in the engine. Improper igniter installation is the number one cause of launch failure. Now we get to the launch controller. This is a device about the size and shape of a candy bar, and is used to control the launch of the rocket. There is a push button and an indicator light. The indicator light verifies when the rocket is ready to launch. This is when the safety key is inserted in the little hole at the top of the controller. The button is pushed to activate the igniter when all launch preparations are complete. The safety key is a little round key attached to the safety cap. The safety cap is placed on top of the launch rod after the rocket is placed on the launch pad. The controller will not launch the rocket as long as the key is not in the hole in the controller. The safety cap blunts the end of the launch rod during launch preparation, preventing accidents. A seventeen foot wire leads from the controller to the rocket. The wire has alligator clips which attach to the igniter wire after it is installed in the engine. The launch pad consists of the launch rod, blast plate, and three legs. The rocket is installed on the launch pad by slipping it into the launch lug on the side of the rocket body. It fits loosely enough to allow the rocket to escape easily during launch. The blast plate protects the area directly under the rocket from escaping gasses from the engine at ignition. Once the rocket is built, follow these steps to launch and retrieve your rocket. Place it on the launch pad, threading the launch rod through the launch lug on the side of the rocket. There may be two launch lugs on taller rockets. Insert the rocket engine in the engine mount at the bottom of the rocket, securing with the engine clip. Insert the igniter wire, making sure there is good contact with the propellant of the engine. Place the safety cap with the key attached to the top of the launch rod. Attach the alligator clips to the leads of the igniter wire. Uncoil the wire from the launch controller to its full length. Make sure all bystanders are at least fifteen feet from the rocket, and make sure they stay there. Remove the safety cap from the top of the launch rod, and place key in hole indicated on controller. Countdown and ignition! The rocket will literally leap from the launch pad at speeds approaching 200 MPH. It will continue to gain altitude until the engine shut down. The rocket will track slightly into the wind. During this phase, the engine will emit tracking smoke to allow you to see the rockets progress. At peak altitude the ejection charge will fire, ejecting the recovery system - parachute or streamers. The rocket will descend to the ground, where you can retrieve it for another launch. As the rocket descends, watch an object in the distance directly behind it. When rocket hits the ground, walk directly towards the object, and you should easily find your rocket. Back To History of the Rocket © 2012 Hobby Hobnob Thursday, September 20, 2012Types Of Rockets - Skill LevelsThere are many different types of rockets available to build. The best way to get started in rocketry is to purchase a set. A rocket set contains just about everything you need to get started - rocket, launch pad, controller, engines, ignite, recovery wadding and igniters. The rocket included is usually a ready to fly rocket, or an E2X level rocket. Some sets contain two rockets. These are usually an E2X and a Skill Level One rocket. Glue and four AA batteries are needed in addition to the kit. Rocket kits are graded by skill level, which is a way of sorting the rockets according to the difficulty of construction. The easiest kits to build are E2X kits with Challenge - Skill Level Three - the most formidable to construct. E2X kits are the easiest rockets to build. Painting is not required, and the gluing is minimal. The decals included with the rocket are stick-on. Assembly of an E2X kit requires less than an hour. The next step up are the Skill Level One, or Beta rocket kits. Beta kits take a little more time and care to assemble. The rocket must be painted, and the fin and motor mount assembly is a little more complex. These kits usually require about two hours or more to build. Explorer Kits - Skill Level Two, are the next level. These kits require more skill to construct and typically take several hours to fashion. The rockets built from these kits are more detailed than Skill Level One kits. Skill Level Three, or Challenge level are currently the highest skill level offered by Estes. These are true ‘craft’ rockets requiring more complex gluing, painting and decaling to produce a really beautiful rocket when finished. There are an amazing variety of rockets to build. Multi-stage rockets are fun, and include the two stage Mongoose and Echostar and the three stage Commanche. A booster rocket engine is required for the initial and secondary stages, with a standard engine used for the final stage. These rockets go the highest of all, and all can be flown as single stage rockets if desired. Back To History of the Rocket © 2012 Hobby Hobnob Wednesday, September 19, 2012Lessons Learned From the Model Rocketry HobbySince their invention by the Chinese many centuries ago, rockets have undergone many changes in both their design and role in human affairs. The Chinese used them as both weapon and amusement. Modern China still has a tradition of fine fireworks. Today, rocketry fills many roles in our society. As amusement, who can resist a good old fashioned fireworks display. Fourth of July, Labor Day and many other summer holidays are invigorated by exciting fireworks displays. Rockets also fulfill an essential role in the defense of our nation. Modern meteorology is dependent upon rockets delivering weather satellites to orbit. These satellites are indispensable for the current early warning systems for storms and hurricanes. And think about how television veiwing has been changed by satellite technology. News, sports, and cultural events from around the world are beamed directly into your living room via rocket delivered satellite. Model rocketry can also be a fascinating hobby. In addition to being just plain fun, it can inspire interests in a variety of related subjects. How the hobbyist pursues these other subjects is up to the individual. Model building is the first and most obvious skill involved in model rocketry. Although a number of rockets can be purchased ready-to-fly, the best ones must be built. Building and painting the rocket is considered to be the best part of rocketry by many hobbyists. Modeling skills are learned in stages, and as the dexterity of the modeler increases, the complexity of the rockets built also increases. Rockets are the gateway to the next frontier - outer space. As such, an interest in rocketry can unlock an interest in astronomy. Studying the positions of the stars and constellations, plus learning planetary and lunar movements can all be a part of the rocketry experience. Think of a knowledge of astronomy as a road map and a rocket as a car. Rocketry will take us to the cosmos, and a knowledge of astronomy will get us around. If the budding rocketeer really enjoys flying rockets, and dreams of flying the real thing, then maybe rocketry will open up a career in astronautics. As our presence in space increases, so will the need for many of the people essential on earth. Colonists and their materials will all have to be delivered to space, and the only practical method is with a rocket. Good rocket designers, builders, flyers, and maintenance personnel will be in high demand. The study of mathematics can also be enhanced with model rocketry. Newton's Law of Motion, physics, and an understanding of aerodynamic forces can all be demonstrated by rocketry. Students of history can also benefit from rocketry. Many of the rocket models are styled after actual rockets. Some of the rockets are military rockets, some are modeled after historically important rockets, and some are models of military airplanes. The hobbyist can build the rocket, and then study the history of the prototype. The space shuttle, Bull Pup, SR-71 Blackbird, and Mercury Atlas rocket are all available as model rockets which can be built and researched. For example the Mercury Atlas was the rocket that carried the first American into outer space .The leading model manufacturer, Estes, has a very nice model of this historically important rocket. Your local hobby shop can help you get started with everything you need for the fascinating hobby of rocketry. Expand your horizons and get started in the hobby of rocketry today. Back To History of the Rocket © 2012 Hobby Hobnob Tuesday, September 18, 2012History of the Rocket and Rocketry Part 2The story of the Mercury Atlas Rocket, and the manned American Space Program begins in the 1920's with a man named Robert Hutchings Goddard. His contributions to the history of the rocket are many. Dr. Goddard's day job was as professor of physics at Clark College (Currently Clark University). Professor Goddard was fascinated with rockets, however, and spent a lot of time designing and building them. Solid propellants, similar to gunpowder only mixed in different proportions to allow slower burning, had powered all rockets previous to Dr. Goddard. This propellant mix was not appreciably different from that of the ancient Chinese who first developed rockets in the early thirteenth century. Dr. Goddard developed the first liquid propellant fueled rocket, which he launched on March 16, 1926, near Auburn, Massachusetts. This was an important development in rocketry for space flight, because gunpowder needs oxygen for fuel, and there is no oxygen in space. Liquid fueled rockets carry their own oxygen for fuel. Unfortunately, Goddard's work was largely ignored in the United States. During this same period (1920's) Russian and German scientists were also working on rocket propulsion, and they didn't ignore Goddard's findings. Dr. Werner Von Braun was a brilliant German scientist who built on Godddard's work. Dr. Braun was one of the principal scientists who developed the V-2 rockets for the German war machine. Goddard's rockets had all been small rockets. The V-2 was the first large liquid fueled rocket. It was first launched on October 3, 1942 from the island of Usedom, near Peennemunde, Germany. The V-2 was an important development in rocketry. As a weapon, it terrified the English, and caused much destruction and death. But it's more important contribution was its peaceful application as a space delivery vehicle. Rocketry history since than has been based on this work. Victorious American forces brought Dr. Braun and other scientists to the United States, along with some V-2 rockets. These and other elements of the German rocket program were essential to the development of the X-1 rocket plane in which Chuck Yeager broke the sound barrier on October 14, 1947. The 1950's saw the beginnings of the Cold War, and its twin the Space Race, a period well remembered by most 'Baby Boomers'. The Russians took the lead in this race with the first orbiting satellite, Sputnik I, launched on October 4, 1957. Sputnik II followed on November 3. 1957. Although the United States was well along with this type of technology, the propaganda value of this feat was invaluable, and Americans were terrified. In an age of atomic weapons, the nation that had an effective missile delivery system had a distinct advantage. The Russian development threw the American space program into a turmoil. X-15 technology would have delivered a 'space plane' in two to three years, but for American politicians, this was too long a time to 'lag behind' the Soviets. The first American satellite, Explorer I, joined Sputniks I and II on January 31, 1958, four months after the initial Soviet launch. The National Aeronautics and Space Administration (NASA) was established by Act of Congress on July 29, 1958. The Americans decided to abandon the slower 'space plane' approach to space flight, and follow the quicker 'rocket' approach. Manned space flight came a step closer to reality with the establishment of the American Mercury and the Russian Vostok space programs. Again, the Russians won this achievement with the launch of Vostok I, and Yuri Garigan became the first man in space on April 12, 1961. Alan Shephard followed on May 5, 1961 to become the first American in space riding a Mercury Atlas rocket named Freedom 7. John Glenn became the first American to orbit the earth in Friendship 7 on February 20, 1962. If you're interested in a more complete story about the Mercury Space Program, and more of Chuck Yeager's story, read The Right Stuff By Tom Wolf. It's an excellent story about America's first steps into space. Back To History of the Rocket © 2012 Hobby Hobnob Monday, September 17, 2012Brief History of the Rocket and RocketryThe beginnings of the history of rocketry are shrouded in the mists of time. Mongol chronicles from 1232 report that the Chinese used "arrows of flying fire" against them in their defense of the city of K'ai-feng . Since they also reported another weapon used which they called "heaven shaking thunder", historians have concluded that this was the first recorded use of gunpowder to make primitive bombs and rockets in history. The Mongols were quick to grasp the new technology, using rockets against Russia in the Battle of Legnica in 1241. The Arabs used rockets in their Iberian campaigns in 1249, and other European powers soon followed. The construction techniques of these first rocket was not recorded, and no rockets have survived. They were probably made of tightly wrapped paper tubes packed with gunpowder. These rockets had a very limited range, and no directional control. A German army colonel, history has not recorded his name, made the first major construction improvement in 1668, constructing rockets from wood which had been wrapped in glue soaked sailcloth. The rocket weighed 132 pounds and contained a 16 pound charge of powder. These rockets had more range than previous one, but rockets were still little used, except in the fireworks displays which had become popular in Europe during this time. An Indian prince - Hyder Ali, made the next major improvement in rocket design. His hammered soft iron rocket body was the first metal body rocket. It could develop higher internal pressure than earlier rockets enabling it to hold a larger powder charge, giving a range of almost a mile. This weapon still had no directional control, but was very effective against cavalry troops if fired em masse either in the air, or sent skimming over the ground. The British found this out, to their dismay, in the wars against India in the 1700’s. This weapon caused a bit of a stir in Europe, giving Sir William Congreve an incentive to experiment with rocket construction. Due to his efforts, black powder mixes and rocket construction were improved and standardized. He developed timed explosives and incendiary charges. He designed eight different rocket sizes with ranges from 1/2 to two miles. The Congreve rocket was used in many military campaigns in Europe and elsewhere. The British Army organized rocket brigades to bombard enemy positions. It was the Congreve rocket bombardment during the war of 1812 which inspired Francis Scott Keye to write The Star Spangled Banner. William Hale designed rocket fins which would cause the rocket to spin, around 1850, giving the rocket more stability, thus improving its accuracy. Advances in artillery pieces outpaced rocket design improvements and artillery displaced the rocket. Rockets still found use in swampy or mountainous terrain where the heavy artillery pieces were hard or impossible to transport. A Swede, Wilhelm Unge, made the next improvement in the rocket. He called his creation an "aerial torpedo", made for defense against dirigibles. His improvements consisted of an improved rocket motor nozzle and a switch from gunpowder to a nitroglycerin based propellant. The Krupp armament firm in Germany obtained the patents for this devise in 1909, and experimented further. About this time, an American named Robert Hutchings Goddard began experiments in rocketry. During W.W.I, he developed small rockets which were the later developed into the bazooka. Besides Goddard, others in the US were experimenting with rockets. Elmer and his son Lawrence Sperry developed an "Arial torpedo" in 1917, which utilized gyroscopic control to allow the rocket to fly to a preselected target. Charles F. Kettering in 1918 designed a rocket which used both gyroscopic and barometric control to achieve both altitude and directional control. By the late nineteenth century, scientists were envisioning rocket powered space flight. This dream began to take shape with additional work from Goddard, who developed the liquid fuel rocket in the 1920's, with the first launch in 1926. He also launched the first instrument carrying rocket in 1929. He proposed the first serious plan to reach the moon with rocket powered flight, and it was Goddard more than anyone else who laid the foundation of the modern space program. The Germans, because of a concentrated effort, were ahead of everyone else in rocket technology at the beginning of W.W.II. Under the direction of Dr. Werner Von Braun, the German Army developed a long range ballistic missile on the isolated island of Peenemunde in the late 1930’s. The Germans utilized a variety of rockets during the war, the most ‘famous’ of which was the V-2, which scourged Britain. Most of these rockets were fired from mobile launchers, which could be hidden from Allied air attack, and moved into position when needed. After the war, most of the initial rocket research was into intercontinental ballistic missile systems which could deliver nuclear weapons to faraway places. Surface to air missals were also made for defense against air attack. Air to air missals were made for blasting other planes out of the sky, and missals were developed to blast targets from the airplane to targets on the ground. The most exciting rocket research, however, was the American and Russian developments which were to launch men into space, as envisioned by Goddard, and about a zillion science fiction writers. The rocket carried men to the moon in 1969, and will enable us to visit the other planets. The rocket and the science of rocketry has been an important story in our history and will become more important as time advances. Lessons Learned From the Model Rocketry Hobby History of the Rocket and Rocketry Part 2 Types Of Rockets - Skill Levels Model Rocket Parts And What They Do How To Build A Model Rocket - Make A Skill Level One Kit Back To Hobbies © 2012 Hobby Hobnob
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Basic information about various hobby and craft topics.
Showing posts with label Rocketry. Show all posts
Showing posts with label Rocketry. Show all posts
