Aspect Ratio Calculator Formula

Understand the math behind the aspect ratio calculator. Each variable explained with a worked example.

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Formulas Used

Aspect Ratio (AR)

aspect_ratio = pow(wingspan, 2) / wing_area

Mean Aerodynamic Chord

mean_chord = wing_area / wingspan

Variables

VariableDescriptionDefault
wingspanWingspan (b)(m)35
wing_areaWing Area (S)(m²)120

How It Works

Wing Aspect Ratio

Aspect ratio (AR) measures how slender a wing is. It is defined as the square of the wingspan divided by the wing planform area, or equivalently, the wingspan divided by the mean chord.

Formula

AR = b² / S

High aspect ratio wings (like gliders, AR > 15) have low induced drag and are efficient for slow, soaring flight. Low aspect ratio wings (like fighters, AR < 5) are better for high-speed maneuverability and structural strength.

Worked Example

A transport aircraft with a 35 m wingspan and 120 m² wing area.

wingspan = 35wing_area = 120
  1. 01AR = 35² / 120 = 1225 / 120
  2. 02AR = 10.208
  3. 03Mean chord = 120 / 35 = 3.429 m

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