Forces of Flight - Air Aerodynamics Flight - Science - Grade 6

Click on the Plane to experiment with the Forces of Flight

When an airplane flies, the wing is designed to provide enough Lift to overcome the airplane’s Weight, while the engine provides enough Thrust to overcome Drag and move the airplane forward. The Thrust of a rocket engine overcomes the Weight of the object to move the rocket forward.

Increasing the weight of an aircraft affects the amount of lift needed. In turn, a larger wing would provide more lift, but that would increase the amount of drag and therefore increase the amount of thrust needed. The forces of flight are interconnected, and a change in one affects the others.


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. Airplanes use airfoils to create lift using Bernoulli’s Principle. Lift is the opposite force to gravity or weight.

Videos: Lift [Airplanes & Gliders]   |   Lift [Hot Air Balloons]

Weight (aka Gravity)

Weight is the force of gravity. It acts in a downward direction - toward the center of the Earth. The lift caused by air rushing over an airfoil, using Bernoulli’s Principle, allows the plane or bird to overcome the force of gravity. Weight is the opposite force to lift.

Video: Weight


Drag is the force that acts opposite to the direction of motion. Drag is caused by friction and differences in air pressure.

By making something more aerodynamic, you reduce the drag, allowing you to go faster and be more energy efficient.

Video: Drag


Thrust is the force that propels a flying machine in the direction of motion. Engines produce thrust.

Without thrust, the airplane or bird would fall to the earth. It is thrust that moves the plane, bird or object through the air.


Thrust [Propellers]

Thrust [Rockets]