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Principles of flight
5.2.1.3 Formulas for lift and drag
The elements involved in calculating the size of lift (L) are:
- Air density (d), the denser the air, the more lift is generated.
- Speed, or more precisely the square of the speed (v²).
- Wing area (s), a larger wing creates more lift.
- The wing's design and angle of attack, resulting in the lift coefficient (cL).
Lift can be described by the formula:
L = ½d*v²*s*cl (L is an abbreviation for Lift)
The relentless companion of lift, drag (D), benefits from the same elements as
lift.
The formula for drag is:
D = ½d*v²*s*cd
The size of cd depends on the wing's design (independent of the angle of attack)
and is called the drag coefficient.
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Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 445
