MotionLab

Lift Force Calculator

The upward force that keeps an aircraft airborne, from wing area, speed, and shape.

Lift coefficient (Cl)

Air density (kg/m³)

Velocity (m/s)

Wing area (m²)

Lift force (N)

17,640

F = ½ρv²ACl

What you entered

Lift coefficient (Cl): 0.5Air density (kg/m³): 1.225Velocity (m/s): 60Wing area (m²): 16

1
F = ½ρv²ACl
0.5 × 1.225 × 60² × 16 × 0.5= 17640 N

Result

Lift force (N): 17,640

At 60 m/s with Cl=0.5, lift force is 17,640 N.

Aerodynamic lift from wing area and airspeed

Lift is half the air density times the lift coefficient, wing area and velocity squared, using 1.225 kg/m3.

Lift coefficient	Velocity (m/s)	Wing area (m2)	Lift (N)
1	50	10	15312.50
1.2	70	16	57624.00
1.5	60	20	66150.00
0.5	100	25	76562.50
0.8	80	30	94080.00

Lift shares its form with drag, so it also grows with the square of airspeed - which is why an aircraft needs a minimum speed to stay airborne and why stall speed rises with weight. The lift coefficient depends on the wing's shape and its angle of attack, rising as the nose comes up until the airflow separates and the wing stalls, at which point the coefficient collapses rather than continuing to climb. Flaps raise the coefficient at low speed, letting an aircraft land slower. Air density falls with altitude and heat, so hot high airfields need longer runways.

Same equation shape as drag, different coefficient

Lift and drag share the same basic formula structure — both depend on air density, the square of velocity, and a reference area — the difference is the coefficient (Cl vs Cd) and the direction of the resulting force relative to airflow.

Why takeoff speed matters so much

Since lift scales with velocity squared, a plane needs to reach a minimum speed before lift force can overcome its weight — below that speed, no amount of wing area alone will get it off the ground.

Frequently asked questions

A Boeing 737 weighs 70,000 kg. At takeoff speed of 80 m/s with wing area 125 m², what lift coefficient is needed?

L = mg = 686,700 N. Cl = 2L/(ρv²A) = 2 × 686700/(1.225 × 6400 × 125) = 1.40. That's achievable with flaps deployed — clean wing Cl is typically 1.0-1.5, and flaps add 0.5-1.0 more.

How is lift different from drag?

Both use the same formula structure (½ρv²A × coefficient), but lift acts perpendicular to airflow (upward for a wing) while drag acts parallel (opposing motion). A well-designed airfoil maximizes the lift-to-drag ratio — commercial aircraft achieve L/D ratios of 15-20. See the drag force calculator.

Why do planes need to fly faster at higher altitudes?

Air density (ρ) decreases with altitude — at 10,000 m it's about 0.41 kg/m³ vs 1.225 at sea level. Since lift depends on ρ, the plane must fly faster to compensate. This is partly why jets cruise at high speed: they need to maintain lift in thin air.

Can a flat plate generate lift?

Yes — even a flat plate tilted at an angle of attack generates lift (and lots of drag). Airfoils are shaped to generate lift more efficiently (higher L/D ratio). A flat plate at 10° angle of attack has Cl ≈ 0.9 but Cd ≈ 0.15, while an airfoil gets Cl ≈ 1.2 with Cd ≈ 0.01.