Beginner's Guide to Rockets

Welcome to the Beginner's Guide to Rockets

The Beginner's Guide to Rockets will help you learn the basic math and physics that govern the design and flight of rockets. We'll look at many different kinds of rockets, from stomp rockets, which are a special kind of artillery shell, to bottle rockets, to model rockets, to full scale boosters. We'll look at the similarities and the differences in these rockets and include some instructions for making and flying your own rockets.
At this Web site you can study how rockets operate at your own pace and to your own level of interest. There is a lot of mathematics at this web site, so we provide background pages on many mathematical topics. The flight of the rocket involves the interaction of forces, so we include background pages on the fundamentals of forces. Aerodynamics plays a major role in the flight of toy rockets and in the generation of thrust for full scale rockets, so there are background pages devoted to basic aerodynamics . There are also background pages on thermodynamics and gas dynamics because of the role they play in rocket propulsion. Since we will be sending rockets to the Moon and Mars , we provide some background information on these planets in addition to our home planet.
The majority of the information at this web site is presented at a high school or early college level, although much of the information can also be used by middle school students and the general public. Information is provided for both students and teachers. The site includes materials that were developed over a ten year span by several different authors, so the pages do not all look the same. We have added navigation buttons to ease movement across and within the work of a given author. Most of the pages are presented in the following format: a graphic at the top which the user can capture and incorporate into their own presentations or class notes; a text explaining the topic presented in the graphic and including many hyperlinks to related topics; navigation links at the bottom to related educational activities, closely related web pages, and an index of all the pages.
Using the Index of Web Pages, you are never more than two clicks away from any other Web page at this site. Just click on the word "Index" at the bottom of any page, and then click to a new page from the index. We have intentionally organized this site to mirror the unstructured nature of the world wide web. However, if you prefer a more structured approach, you can also take one of our Guided Tours through the site. Each tour provides a sequence of pages dealing with some type or aspect of rockets. Web pages that include Interactive Java applets are noted in the index. RocketModeler II, RocketThrust Simulator, and the AtmosModeler Simulator are provided to encourage students to explore science and math. The programs allow students to design and fly rockets on their personal computer and can be downloaded to operate off-line. Additional Classroom Activities are also available at this site.
This site was prepared at the NASA Glenn Research Center in support of the Educational Programs Office and was funded by the Exploration Systems Mission Directorate. Many of the pages at this site were prepared to support videoconferencing for teachers and students as provided by the Digital Learning Network. Much of the information available in the Rockets Educator's Guide publication is available on-line at this site

Beginner's Guide to Compressible Aerodynamics

Welcome to the Beginner's Guide to Compressible Aerodynamics
High speed aerodynamics is a special branch of the study of aeronautics. It is often called compressible aerodynamics because, in this flight regime, the compressibility effects of air can not be neglected. The flight regime is characterized by the Mach number which is the ratio of the speed of the aircraft to the local speed of sound. Flight less than the speed of sound is called subsonic, near the speed of sound is transonic, greater than the speed of sound is supersonic, and very much greater than the speed of sound is hypersonic. Different flow phenomenon are present in each of the various flight regimes.
At this Web site you can study high speed aerodynamics at your own pace and to your own level of interest. Some of the topics included are: isentropic flows, oblique, and normal shock waves, and multiple shock interactions. Because high speed aerodynamics involves the generation of heat, there are several pages devoted to basic gas properties, how those properties change through the atmosphere, and some basic thermodynamics.
This site was prepared at NASA Glenn to provide background information on high speed aerodynamics for undergraduates, professionals, and life-long learners. There is a particular emphasis here on the math and science involved with high speed aerodynamics. High school students should be able to make sense of the math and science principles. We include many, small, interactive calculators and simulators which solve the flow equations and are provided to aid your understanding.
This site has been intentionally organized to mirror the unstructured nature of the world wide web. There are many pages here connected to one another through hyperlinks and you can then navigate through the links based on your own interest and inquiry. There is an index of topics that you can access from any page, so you are never more than two clicks away from any other Web page at this site. However, if you prefer a more structured approach, you can also take one of our Guided Tours through the site. Each tour provides a sequence of pages dealing with some aspect of aerodynamics

Beginner's Guide to Propulsion

Welcome to the Beginner's Guide to Propulsion
What is propulsion? The word is derived from two Latin words: pro meaning before or forwards and pellere meaning to drive. Propulsion means to push forward or drive an object forward. A propulsion system is a machine that produces thrust to push an object forward. On airplanes, thrust is usually generated through some application of Newton's third law of action and reaction. A gas, or working fluid, is accelerated by the engine, and the reaction to this acceleration produces a force on the engine.
A general derivation of the thrust equation shows that the amount of thrust generated depends on the mass flow through the engine and the exit velocity of the gas. Different propulsion systems generate thrust in slightly different ways. We will discuss four principal propulsion systems: the propeller, the turbine (or jet) engine, the ramjet, and the rocket.
Why are there different types of engines? If we think about Newton's first law of motion, we realize that an airplane propulsion system must serve two purposes. First, the thrust from the propulsion system must balance the drag of the airplane when the airplane is cruising. And second, the thrust from the propulsion system must exceed the drag of the airplane for the airplane to accelerate. In fact, the greater the difference between the thrust and the drag, called the excess thrust, the faster the airplane will accelerate.
Some aircraft, like airliners and cargo planes, spend most of their life in a cruise condition. For these airplanes, excess thrust is not as important as high engine efficiency and low fuel usage. Since thrust depends on both the amount of gas moved and the velocity, we can generate high thrust by accelerating a large mass of gas by a small amount, or by accelerating a small mass of gas by a large amount. Because of the aerodynamic efficiency of propellers and fans, it is more fuel efficient to accelerate a large mass by a small amount. That is why we find high bypass fans and turboprops on cargo planes and airliners.
Some aircraft, like fighter planes or experimental high speed aircraft, require very high excess thrust to accelerate quickly and to overcome the high drag associated with high speeds. For these airplanes, engine efficiency is not as important as very high thrust. Modern military aircraft typically employ afterburners on a low bypass turbofan core. Future hypersonic aircraft will employ some type of ramjet or rocket propulsion.
The site was prepared at NASA Glenn by the Learning Technologies Project (LTP) to provide background information on basic propulsion for secondary math and science teachers. The pages were originally prepared as teaching aids to support EngineSim, an interactive educational computer program that allows students to design and test jet engines on a personal computer. Other slides were prepared to support LTP videoconferencing workshops (http://www.grc.nasa.gov/WWW/K-12/CoE/Coemain.html) for teachers and students. And other slides were prepared as part of Power Point Presentations for the Digital Learning Network.
There is a special section of the Beginner's Guide which deals with compressible, or high speed, aerodynamics. This section is intended for undergraduates who are studying shock waves or isentropic flows and contains several calculators and simulators for that flow regime.
We have intentionally organized this site to mirror the unstructured nature of the world wide web. There are many pages here connected to one another through hyperlinks. You can then navigate through the links based on your own interest and inquiry. However, if you prefer a more structured approach, you can also take one of our Guided Tours through the site. Each tour provides a sequence of pages dealing with some aspect of propulsion.

Beginner's Guide to Aerodynamics

Welcome to the Beginner's Guide to Aerodynamics
What is aerodynamics? The word comes from two Greek words: aerios, concerning the air, and dynamis, which means force. Aerodynamics is the study of forces and the resulting motion of objects through the air. Judging from the story of Daedalus and Icarus, humans have been interested in aerodynamics and flying for thousands of years, although flying in a heavier-than-air machine has been possible only in the last hundred years. Aerodynamics affects the motion of a large airliner, a model rocket, a beach ball thrown near the shore, or a kite flying high overhead. The curveball thrown by big league baseball pitchers gets its curve from aerodynamics.
At this Web site you can study aerodynamics at your own pace and to your own level of interest. Some of the topics included are: Newton's basic equations of motion; the motion of a free falling object, that neglects the effects of aerodynamics; the terminal velocity of a falling object subject to both weight and air resistance; the three forces (lift, drag, and weight) that act on a glider; and finally, the four forces that act on a powered airplane. Because aerodynamics involves both the motion of the object and the reaction of the air, there are several pages devoted to basic gas properties and how those properties change through the atmosphere.
This site was prepared at NASA Glenn by the Learning Technologies Project (LTP) (http://www.grc.nasa.gov/WWW/K-12) to provide background information on basic aerodynamics as teaching aids for math and science teachers. Some of the slides were prepared to support FoilSim, an interactive educational computer program that allows students to design and test airfoil shapes on a personal computer. Other slides were prepared to support LTP videoconferencing workshops (http://www.grc.nasa.gov/WWW/K-12/CoE/Coemain.html) for teachers and students. And other slides were prepared as part of Power Point Presentations for the Digital Learning Network.
This site has been intentionally organized to mirror the unstructured nature of the world wide web. There are many pages here connected to one another through hyperlinks and you can then navigate through the links based on your own interest and inquiry. There is an index of topics that you can access from any page, so you are never more than two clicks away from any other Web page at this site. However, if you prefer a more structured approach, you can also take one of our Guided Tours through the site. Each tour provides a sequence of pages dealing with some aspect of aerodynamics