Technology Interactions

1. Air and space technologies rely on aerospace—the study of how things fly. Technology Interactions

2. To Fly Like a Bird • Humans tried using feathers and wood to construct wings like a bird’s. • Humans don’t have the muscle power and hollow bone structure to fly like birds. • Humans learned to use technology to fly.

3. What Makes Things Fly? • An object will not change speed or direction unless a force acts on it. • Thrust is a forward force. • Lift is an upward force. • Fluid friction, or drag, slows down a moving object. Gravity pulls objects toward earth. • Momentum is the connection between how fast an object is moving and the mass of the object.

4. Thrust • On jet airplanes, thrust is created by the plane’s engines. • On propeller planes, engines make the propellers spin, creating thrust.

5. Lift • The Bernoulli effect: a fast-moving fluid exerts less pressure than a slow-moving fluid. • Airfoil: a shape designed to produce useful motion from the flow of air. • Wings and propellers are airfoils that help create lift.

6. Controlling Propeller Airplanes • Ailerons make the plane roll from side to side.

7. Controlling Propeller Airplanes • The rudder makes the plane turn left or right.

8. Controlling Propeller Airplanes • Elevators make the plane dive and climb.

9. Jet Engines • Jet engines use Newton’s third law of motion: for every action, there is an equal and opposite reaction.

10. Rockets • Rockets use Newton’s third law of motion. • Rockets carry their own oxygen with them so they can operate in space. • The nozzle at the base of a rocket’s engine can swivel to direct the hot gases in different directions, allowing the rocket to change direction. • Rockets are powered by solid fuel boosters or liquid fuel boosters.

11. Solid Fuel Boosters • Solid fuel boosters contain a solid propellant. • Once solid fuel is ignited, it must burn completely.

12. Liquid Fuel Boosters • Liquid fuel boosters burn liquid hydrogen and oxygen. • Liquid fuel engines can be turned on and off.