What is Aspect Ratio?

Question

In terms of aircraft design

Answer 1

The relationship between the wing cord length and span. Long thin wing has a high aspect ratio. Short stubby, low aspect ratio.

Answer 2

Wing aspect ratio = wing span²/wing area.

The aspect ratio of a circular airfoil is 4/π.

Answer 3

As the previous answer, but to clarify the chord is a line between the leading edge and the trailing edge. The span is wing root to tip.

and with a swept back wing that isnt quite as simple as you think, the line is across the wing parallel to the fuselage and along the wing at right angles to the fuselage.