Aerodynamic Lift Force
Aerodynamic Lift Force
Lift is the upward force a wing produces; it scales with the square of speed and is the reason aircraft fly.
The lift is L = ½·ρ·v²·S·C_l. where ρ is air density, v the speed, S the wing area and C_l the lift coefficient.
Inputs
rho := 1.225 kg/m^3=1.23 kg/m^3
v := 70 m/s=70 m/s
S := 30 m^2=30 m^2
C_l := 0.9=0.9
Apply the lift equation.
L := 0.5·rho·v^2·S·C_l=81033.75 N
Results
Lift must equal weight in level flight. Because it grows with v², a wing produces little lift slowly — which is why aircraft need high take-off and landing speeds or high-lift devices.
Assumptions & limitations
- Subsonic, attached flow.
- Constant lift coefficient.
- Standard air density.