Observe: Types of Propulsion

Think about how swimmers move through the water. How do they produce thrust to move forward?

Swimmers use their legs to kick and their arms to push the water backwards.  By pushing the water back,  their bodies move forward.  This is an example of propulsion.

The principle upon which the idea of propulsion works is called Newton’s Third Law, which states,
“For every action, there is an equal and opposite reaction.”

An engine is used to push something (air, exhaust) backwards.  The resulting equal and opposite reaction is that the aircraft is pushed forwards. 

Aircraft use various methods for propulsion.  The type of propulsion used depends on the size of the aircraft and the type of flying it will be doing.


  Video

View this ADLC Digital Lesson to learn more about propulsion.


  Notebook: What are the various methods for propulsion?

  1. Click here to download this activity. 
  2. Complete the activity using the links provided (in the activity and below)
  3. Save to your Flight Notebook.     
Activity Links:


  Check Your Answers

Topic: Propulsion

(What is the website about?)

Main Ideas: Complete the blanks with the missing words
Propulsion
  1. What is thrust used for?
  • forward motion
  • acceleration
  • altitude gain
  • maneuvers

Propellers ( watch the video)
  1. What is propulsion?
  • moving or pushing an object forward
  1. What does a propeller do?
  • An engine spins the propeller to produce “lift” in the forward direction.
  1. How is a propeller shaped and why?
  • A propeller is shaped like a wing to produce high pressure on one side and low pressure on the other side (for lift to occur).

Engines
  1. How do engines produce thrust?
  • Fuel is mixed with oxygen in the combustion chamber.
  • The fuel mixture is ignited.
  • The burning produces hot, expanding gases.
  • The expanding gases produce thrust directly or are used to move pistons or a turbine.
  1. What are the three types of engines?
    (Click each one if you want to see how they work.)
  • Piston engine – used to turn a propeller
  • Jet engine – increases pressure inside the engine
  • Rocket engine – increases pressure inside the engine

Rocket Propulsion ( watch the video)
  1. Why cannot rockets use jet engines and propellers?
  • Space has no air.
  • Air is needed to turn propellers and to burn fuel in jet engines.
  • Rocket engines carry their own oxygen (or other oxidizers).
  1. How do rockets produce propulsion?
  • Fuel and oxidizers burn inside the engine
  • The exhaust produced pushes in one direction and the rocket is then pushed in the opposite direction.  (Newton’s Third Law)
  1. What is Newton's Third Law?
  • For every action there is an equal and opposite reaction.