Why Do Some Airplanes Have Curved Wingtips?

While nearly all commercial airplanes have two wings, the way in which these wings are designed varies. Some airplanes, for example, have flat wings, whereas others have wingtips that bend or curve upwards. Unless you’re familiar with aviation mechanics, you might be wondering how these bent or curved wingtips affect an airplane’s performance. After all, conventional wisdom may lead you to believe that flat wings offer the greatest lift. There’s a justifiable reason behind the use of curved wingtips, which we’re going to explore in this blog post.

Curved Wingtips Separate High and Low Pressure

Aside from looking nice, curved wingtips offer practical benefits for pilots and airlines by separating high air pressure and low air pressure during an airplane’s flight. When an airplane is flying, the wings create separate areas of air pressure. Above the wings is high air pressure and below the wings is low air pressure. The difference in pressure creates lift, pulling the airplane up into the air as it takes off and ascends.

With straight, flat wingtips, however, high air pressure above the airplane is pulled to the sides of the wings where it curls over the wingtips and mixes with the low air pressure below the airplane. This phenomenon is said to create pockets of turbulent air known as wake vorticles.

How Wake Vorticles Affect an Airplane’s Performance

Although they are invisible to the naked eye, wake vorticles — the pockets of turbulent air created when high air pressure flows underneath an airplane and mixes with low air pressure — can still negatively impact an airplane’s performance. As wake vorticles form below the airplane, they create resistance by slowing it down. This doesn’t necessarily mean that airplanes will fly at a slower speed when exposed to a wake vorticle. Rather, they’ll have to consume more energy to maintain their speed. Of course, this means airplanes will use more fuel, which is already one of the biggest operational expenses for commercial airlines.

Curved Wingtips to Prevent Wake Vorticles

There’s a simple way to prevent wake vorticles, however: curved wingtips. As shown in the image above, curved wingtips are pointed upwards just slightly at the very tip. The purpose of these curved wingtips is to prevent high air pressure above the airplane from flowing over and under the wings. As the high air pressure pushes across the wings, it encounters the curved wingtips where it’s blocked. This doesn’t necessarily prevent all wake vorticles from forming, but it plays a key role in reducing the frequency and size of wake vorticles.