Induced Drag Calculator

Induced Drag Formula

Worked Example

A wing at C_L = 0.6 with aspect ratio 8 and elliptic loading:

1. C_Di = C_L² ÷ (π e AR) = 0.6² ÷ (π × 1 × 8)
2. C_Di = 0.01432394488
3. αᵢ = C_L ÷ (πAR) = 0.02387324146 rad = 1.367835979°

Induced angle of attack αᵢ (elliptic): 1.367835979 ° · Downwash angle at the wing (elliptic) = αᵢ: 1.367835979 °

GATE tip

Prandtl lifting-line theory: elliptic lift distribution gives the minimum induced drag with e = 1 and a constant downwash along the span.

More Aerodynamics Calculators

• Thin Airfoil Theory Calculator

  c_l = 2π(α − α_L0), a = a₀/(1 + a₀/(πeAR))

  Kutta–Joukowski L′ = ρV∞Γ, so Γ = ½V∞ c c_l

  Example: A cambered airfoil (α_L0 = −2°) at 5° on a wing of aspect ratio 8: Section lift coefficient c_l = 0.767636.

  Open the thin airfoil theory calculator →

• Boundary Layer Calculator

  Laminar: δ = 5x/√Reₓ, c_f = 0.664/√Reₓ

  δ* = 1.7208x/√Reₓ, θ = 0.664x/√Reₓ; turbulent δ = 0.37x/Reₓ^0.2, c_f = 0.0592/Reₓ^0.2

  Example: Air at 10 m/s, 0.5 m from the leading edge (ν = 1.46 × 10⁻⁵ m²/s): Boundary-layer thickness δ = 4.272 mm.

  Open the boundary layer calculator →

• Pitot Tube Calculator

  V = √(2(p₀ − p)/ρ)

  subsonic M = √((2/(γ−1))[(p₀/p)^((γ−1)/γ) − 1]); supersonic: Rayleigh formula p₀₂/p₁(M₁)

  Example: A low-speed pitot reading 1000 Pa dynamic pressure in sea-level air: Airspeed V = 40.4061 m/s.

  Open the pitot tube calculator →

Frequently asked questions

Sources

• The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures .

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.