Technology
How do airplanes fly?
Airplanes fly by balancing four forces: lift, weight, thrust, and drag. The wings are shaped so air moving over them generates lift — an upward force that overcomes the plane's weight — while engines provide thrust to push the plane forward fast enough for the wings to work.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how an airplane works.
Step by step
- 1Four forces act on a plane: lift (up), weight (down), thrust (forward), and drag (back).
- 2Wings (airfoils) deflect air downward, and by Newton's third law the air pushes the wing up — that's lift.
- 3Engines (jet or propeller) provide thrust to move the plane forward through the air.
- 4To climb, lift exceeds weight; in level flight, the four forces are balanced.
- 5Control surfaces — flaps, ailerons, rudder, and elevators — let the pilot steer and adjust lift.
Frequently asked questions
- What actually creates lift?
- Wings deflect air downward as they move through it; in reaction, the air pushes the wing upward. Both the wing's shape and its angle to the airflow contribute to this lift.
- Why don't planes fall when the engines idle?
- As long as air flows fast enough over the wings, they keep generating lift. A plane can glide and descend gradually even without engine thrust.
- How do heavy planes get off the ground?
- Engines accelerate the plane until air moves over the wings fast enough that lift exceeds the plane's weight — then it rises off the runway.