How Airplanes Fly
Understand lift, drag, thrust, and control well enough to explain any flight from takeoff roll to touchdown.
This course is for members
$9 unlocks every course in the library, this one included, plus a credit to build a topic of your own and at least 10 new courses every month.
What you will learn about How Airplanes Fly
The 7-day sprint
- The Four Forces. Every airplane in flight is a balance of four forces: lift up, weight down, thrust forward, and drag back.
- Air Is a Fluid With Weight. Air has mass and pressure, and the force it can generate rises with its density and with the square of the airplane's speed through it.
- How a Wing Makes Lift. A wing produces lift by turning oncoming air downward; the airfoil shape and angle of attack create a pressure field with low pressure on top and higher pressure below.
- Drag and the Cost of Lift. Drag comes in two families: parasite drag that grows with speed, and induced drag created by lift itself that shrinks with speed.
- Thrust: Propellers and Jets. Propellers and jet engines both make thrust the same way, by accelerating air rearward, and they differ mainly in how much air they move and how fast.
- Control and Stability. An airplane rotates about three axes controlled by elevator, ailerons, and rudder, and its natural stability comes from where the center of gravity sits relative to the lift and tail forces.
- The Whole Flight, Start to Finish. A flight is a managed trip around the airplane's envelope, trading speed, altitude, angle of attack, and configuration to stay between stalling too slowly and overstressing too fast.
The 80/20: the 6 concepts that matter most
- Angle of Attack Rules Everything
- Lift Grows With Speed Squared and With Air Density
- Lift and Drag Are a Package Deal
- Thrust Is Reaction, and Excess Thrust Is Climb
- Stability Comes From Balance Points, Not Magic
- Elevator Sets Speed, Power Sets Altitude
The core idea, explained like you are 5
A wing flies because it continuously throws air downward, and the air pushes back up with an equal force.
Then the quiz and the ladder
10 questions that correct you when you are wrong, and beginner, intermediate, advanced levels, each with a practical exercise.