Aircraft Wings Come in All Shapes and Sizes

When an aircraft designer is choosing a wing, they not only have to take into consideration the aerodynamic factors but also the cost of manufacturing, weight, and maintainability. Manufacturers have assorted budgets and design aircraft with different operating requirements, so they have to weigh the pros and cons of opposing factors. For example, a defense aircraft will focus more on speed and maneuverability, while airliners will focus more on range, comfort, and efficiency. Airliners can utilize higher aspect ratios— span divided by the mean chord— to increase lift and support higher loads; however, fighters will have lower aspect ratios to reduce drag and increase maneuverability. As such, when choosing the optimal aircraft wing, an engineer must consider a few factors such as airfoil selection, wing planform, and wing configuration.

An airfoil is the cross section of a wing— it’s what you would see if the wing was cut in half— and it affects aircraft performance. Because there is less drag when the aircraft fuselage is aligned with the wind, the wing is attached to the fuselage at a fixed effective angle of attack, otherwise known as an incident angle. The main determinant for lift is the angle of attack. Thick wings have a structural advantage because they don't require external bracing— however, both produce different forms of drag. The chord is an imaginary line connecting the leading and trailing edge of a wing. The camber of the wing defines the difference between the curvature of the upper and lower surfaces— it affects when and how a wing stalls. Positively cambered wings produce more lift before stalling and have higher load capacities, while a sharper wing produces less lift before stalling and supports lower loads. The benefit of a sharper wing is maneuverability, higher speed capacity, and less drag; as a result, they are often used for fighter aircraft.

The wing planform is what you see if you look at an aircraft from above. It's determined by wing loading, aspect ratio, sweep, taper, and twist. Wing loading is the ratio of the wing area to the weight of the plane, which determines speed capacity, runway requirements, and power requirements. Commercial aircraft have higher wing loading than a trainer. Swept wings reduce drag at high speeds and are more stable. A wing is tapered when the chord is shorter at the tip than the root— it adjusts the load and minimizes drag— but it's more complex to manufacture. Wings twist at the top because it allows the root to stall first— which helps the pilot get out of a spin before losing complete control.

Wing configuration is the view of the wing from the front of an aircraft. A dihedral is a V-shape and adds stability to the aircraft. An anhedral is the opposite, it's destabilizing and increases maneuverability. Wings can be mounted on the fuselage at a high point, low point, or right in the middle. The position is often chosen based on sightlines and cargo loading. Winglets may also be added to increase efficiency without increasing the wingspan. Increasing the span can be more complicated, add more weight, and make the wingspan too long to fit at airport gates.