READ: open the highlighted link above & read the following topics listed below.
FORCES OF FLIGHT
- The Four Forces
- We Aren't Built to Fly
- Gravity keeps us Down to Earth
- Air is Stuff
- Air Motion
- Friction Drag
- Shock Waves
- Vortex Drag
STRUCTURES & MATERIALS
- How Wings Work
- Forces of Flight
Watch the following video's to clarify the forces.
(click on the highlighted word)
DRAG - Drag is the force that acts opposite to the direction of motion. Drag is caused by friction and differences in air pressure.
Lift is the force that acts at a right angle to the direction of motion through the air. Lift is created by differences in air pressure.
THRUST - Thrust is the force that propels a flying machine in the direction of motion. Engines produce Thrust.
WEIGHT - Weight is the force of gravity. It acts in a downward direction—toward the center of the Earth.
Weight is the force of gravity. It acts in a downward direction—toward the center of the Earth.
When an airplane is flying straight and level at a constant speed, the lift it produces balances its weight, and the thrust it produces balances its drag. However, this balance of forces changes as the airplane rises and descends, as it speeds up and slows down, and as it turns.