Why Does a Wing Hold a Plane Up?

Step 1 of 5

A wing pushes air downward as it passes.

Air arriving level is bent by the tilted, curved surface and leaves heading noticeably downward, in a steady stream behind the aircraft.

Step 2 of 5

Push air down and it pushes you up.

Every push has an equal push the other way, so continuously shoving air downward means the air is continuously shoving the wing upward.

Step 3 of 5

The curve helps by turning more air.

A flat plate held at an angle does generate lift, but a properly curved wing bends far more air smoothly and with much less drag.

Step 4 of 5

Speed matters more than anything else.

Lift grows with the square of speed, so flying twice as fast gives four times the lift, and slowing to half gives only a quarter.

Step 5 of 5

Too steep and the air stops following.

Beyond a certain angle the smooth flow breaks away from the upper surface, the wing stops turning air downward, and the lift collapses.

A loaded airliner wing carries around 600 kilograms on every square metre, which needs roughly 250 km/h before it becomes possible.