Free Induced Drag Calculator

Calculate the induced drag coefficient and force from lift coefficient, aspect ratio, and Oswald efficiency factor.

Pa

Induced Drag Coefficient (CDi)

0.00936

Induced Drag Force4,681.0 N

Induced Drag Coefficient (CDi) vs Lift Coefficient (CL)

Induced Drag

Induced drag is the aerodynamic penalty of generating lift. It arises because the wing creates trailing vortices that tilt the local flow downward, effectively rotating the lift vector backward.

Formula

CDi = CL² / (pi × e × AR)

where CL is the lift coefficient, e is the Oswald span efficiency (typically 0.7 to 0.9), and AR is the aspect ratio. Induced drag dominates at low speeds and high CL, which is why it is critical during takeoff and climb.

Example Calculation

A wing with CL=0.5, AR=10, e=0.85, at q=5000 Pa with S=100 m².

  1. 01CDi = 0.5² / (pi × 0.85 × 10)
  2. 02CDi = 0.25 / (26.704) = 0.00936
  3. 03Di = 0.00936 × 5000 × 100 = 4681 N

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