This is a perfect square that is one by one metre in size. The term ratio is defined by how many times one number contains another number. The aspect ratio of a shape is the ratio of its size. So the aspect ratio of this square is 1 to 1. The aspect ratio of this video is 16 to 9. This rectangular wing of an aeroplane has an aspect ratio as well. It's defined as the wingspan divided by its chord. If the wing has a 20 metre wingspan and a 1 metre chord, the aspect ratio is 20. This is an example of a high aspect ratio wing. A wing that has a 10 metre wingspan and a 2 metre chord has an aspect ratio of 5. This is an example of a low aspect ratio wing.

You can also calculate the aspect ratio by this formula, the square root of wingspan divided by the wing area. As you can see, the solution is also 5. Please note that the wing area in this formula is not the upper and lower surface area of the wing. The value for the wing area is the area of its shape as viewed from above. This version of the formula is particularly useful when calculating the aspect ratio of a wing that is not rectangular, such as this swept back airliner wing. By and large, high aspect ratio wings generate less induced drag, have a higher lift to drag ratio, and make aeroplanes more stable in flight. Low aspect ratio wings allow aeroplanes to be more manoeuvrable, Reduce the adverse yaw effect and are easier to design and build.