Aspect ratio is calculated as?

Aspect ratio is a critical concept in aerodynamics that describes the relationship between the wingspan of an aircraft and its mean chord length. Specifically, it is calculated as the wingspan (the distance from tip to tip of the wings) divided by the mean chord (the average width of the wing).

A higher aspect ratio indicates longer, narrower wings, which can lead to greater aerodynamic efficiency, reduced drag, and improved lift characteristics. This is particularly beneficial for aircraft designed for gliding or long-distance flight, as it promotes greater lift-to-drag ratios.

In contrast, other options do not accurately represent the concept of aspect ratio. The ratio of weight to lift relates to the overall performance and stability of the aircraft but doesn't define the geometric relationship that aspect ratio captures. The ratio of airspeed to drag is associated with performance metrics rather than wing geometry. The lift-to-thrust ratio concerns propulsion and flight performance but is unrelated to the physical dimensions of the wings.

Thus, the correct perspective on aspect ratio is its definition as the ratio of wingspan to mean chord, which plays a significant role in determining an aircraft's aerodynamic efficiency and overall flight characteristics.