Rockets

1. Rockets

2. What is a Rocket?? • The word "rocket" can mean different things. Most people think of a tall, thin, round vehicle. They think of a rocket that launches into space. "Rocket" can mean a type of engine. The word also can mean a vehicle that uses that engine.

3. How Does a Rocket Engine Work? • Like most engines, rockets burn fuel. Most rocket engines turn the fuel into hot gas. The engine pushes the gas out its back. The gas makes the rocket move forward.A rocket is different from a jet engine. A jet engine needs air to work. A rocket engine doesn't need air. It carries with it everything it needs. A rocket engine works in space, where there is no air.There are two main types of rocket engines. Some rockets use liquid fuel. The main engines on the space shuttle orbiter use liquid fuel. The Russian Soyuz uses liquid fuels. Other rockets use solid fuels. On the side of the space shuttle are two white solid rocket boosters. They use solid fuels. Fireworks and model rockets also fly using solid fuels.

4. Why Does a Rocket Work? • In space, an engine has nothing to push against. So how do rockets move there? Rockets work by a scientific rule called Newton's third law of motion. English scientist Sir Isaac Newton listed three Laws of Motion. He did this more than 300 years ago. His third law says that for every action, there is an equal and opposite reaction. The rocket pushes on its exhaust. The exhaust pushes the rocket, too. The rocket pushes the exhaust backward. The exhaust makes the rocket move forward.This rule can be seen on Earth. Imagine a person standing on a skateboard. Imagine that person throwing a bowling ball. The ball will go forward. The person on the skateboard will move, too.

5. When were Rockets Invented? • The first rockets we know about were used in China in the 1200s. These solid rockets were used for fireworks. Armies also used them in wars. In the next 700 years, people made bigger and better solid rockets. Many of these were used for wars too. In 1969, the United States launched the first men to land on the moon using a Saturn V rocket.

6. Ideal Rocket Definition • A rocket is a missile, spacecraft, aircraft or other vehicle that obtains thrust from a rocket engine. Rocket engine exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction. Rocket engines push rockets forward simply by throwing their exhaust backwards extremely fast, and relying on momentum, air fins, guidance rockets and/or gravity to help control flight.

7. The 4 Forces on a Rocket

8. Liquid vs. Solid Fueled Rockets

9. How are Fireworks Similar toRockets • After watching the “How its Made” video on how fireworks are made complete the following: • Draw a diagram of a firework • Complete a one paragraph write-up of how fireworks are similar to rockets as we currently think of them (space rockets, missiles, etc…

10. Example Firework Diagram

11. Major Components of a Full Scale Rocket • Structural System or Frame • Payload System • Guidance System • Propulsion System

12. Structural Systems • The structural system of a rocket includes all of the parts which make up the frame of the rocket; the cylindrical body, the fairings, and any control fins. The function of the structural system is to transmit the loads from the forces generated during the flight and to provide low aerodynamic drag for flight through the atmosphere.

13. Structural Systems Cont. • The distribution of the structural weight also affects the center of gravity of the rocket which, in turn, affects the stability and control of the rocket.

14. Payload Systems • The payload of a rocket depends on the rocket's mission. The payload of a rocket is essentially what it is carrying. • People • Equipment • Satellite • Explosives • Etc….

15. Guidance Systems • The guidance system of a rocket includes very sophisticated sensors, on-board computers, radars, and communication equipment. The guidance system has two main roles during the launch of a rocket; to provide stability for the rocket, and to control the rocket during maneuvers.

16. Guidance Systems Cont. • The motion of any object in flight is a combination of the translation of the center of gravity and the rotation of the object about its center of gravity. Many different methods have been developed to control rockets in flight. All of the control methods produce a torque about the rocket's center of gravity which causes the rocket to rotate in flight.

17. Propulsion Systems • The propulsion of a rocket includes all of the parts which make up the rocket engine; the tanks pumps, propellants, power head, and rocket nozzle . The function of the propulsion system is to produce thrust.

18. Propulsion Systems Cont. • In a rocket engine , fuel and a source of oxygen, called an oxidizer, are mixed and exploded in a combustion chamber. The combustion produces hot exhaust which is passed through a nozzle to accelerate the flow and produce thrust.

19. Propulsion Systems Cont. • There are two main categories of rocket engines; liquid rockets and solid rockets. In a liquid rocket, the propellants, the fuel and the oxidizer, are stored separately as liquids and oxygen are pumped into the combustion chamber of the nozzle where burning occurs. In a solid rocket, the propellants are mixed together and packed into a solid cylinder.

20. Propulsion Systems Cont. • Under normal temperature conditions, the propellants do not burn; but they will burn when exposed to a source of heat provided by an igniter. Once the burning starts, it proceeds until all the propellant is exhausted. With a liquid rocket, you can stop the thrust by turning off the flow of propellants; but with a solid rocket, you have to destroy the casing to stop the engine. Liquid rockets tend to be heavier and more complex because of the pumps and storage tanks.